REALPRODUCER USER S GUIDE

Transcription

1 REALPRODUCER USER S GUIDE RealProducer 13.1 Revision Date: 21 January 2010

2 RealNetworks, Inc. P.O. Box Seattle, WA U.S.A. Copyright RealNetworks, Inc. All rights reserved. Information in this document is subject to change without notice. All rights reserved. No part of this book may be reproduced, in any form or by any means, without permission in writing from RealNetworks, Inc. Helix, the Helix logo, the Real "bubble" (logo), RealProducer, Helix Producer, RealSystem Server, Helix Universal Server, RealAudio, RealVideo, RealMedia, RealPlayer, and RealOne Player are all trademarks or registered trademarks of RealNetworks, Inc. Other product and corporate names may be trademarks or registered trademarks of their respective owners Copyright (c) RealNetworks, Inc. This product may incorporate one or more of the following: U.S. Patent # 5,917,835; U.S. Patent # 5,854,858; U.S. Patent # 5,917,954; U.S. Patent # 6,597,961; U.S. Patent #6,314,466. Other U.S. patents pending. All rights reserved. RealNetworks Lossless audio codec Copyright (c) RealNetworks, Inc. All rights reserved. RealNetworks RealAudio Multichannel Codec Copyright (c) 2003 RealNetworks, Inc. All rights reserved. ACELP(r).net codec by VoiceAge Corporation Copyright(c) All rights reserved. AAC and aacplus implementation developed by Coding Technologies. All rights reserved. The Ogg Multimedia Framework and the Vorbis audio compression tools have been provided by the Xiph.org Foundation. RealNetworks RealVideo 8 video codec Copyright (c) RealNetworks, Inc. Portions Copyright (c) Intel Corporation. All rights reserved. RealNetworks RealVideo 9 video codec Copyright (c) RealNetworks, Inc. Portions Copyright (c) Intel Corporation. All rights reserved. RealNetworks RealVideo 10 video codec Copyright (c) RealNetworks, Inc. Portions Copyright (c) Intel Corporation. All rights reserved. STLport (c) 1999, 2000 Boris Fomitchev. Copyright (c) 1994 Hewlett-Packard Company. Copyright (c) 1996,97 Silicon Graphics Computer Systems, Inc. Copyright (c) 1997 Moscow Center for SPARC Technology. Helix, RealAudio, RealNetworks, RealSystem, RealVideo, and SureStream are trademarks or registered trademarks of RealNetworks, Inc. All other companies or products listed herein are trademarks or registered trademarks of their respective owners. All rights reserved.

3 CONTENTS INTRODUCTION 1 How This Guide Is Organized... 1 Conventions Used in this Guide... 3 PART I: GETTING STARTED 1 INSTALLATION 7 System Requirements... 7 Installing on Windows... 7 Windows.Net RunTime... 8 Uninstalling the Program CODECS AND FILE FORMATS 11 Input Formats...11 Uncompressed Input Formats...11 Formats Requiring DirectX...11 Formats Requiring QuickTime...12 Output Choices...12 RealMedia...12 Audio Codec Choices...13 RealAudio...13 Video Codec Choices...17 RealVideo...17 Multi-Rate Streams...18 Rate Shifting...19 Encoding Requirements for Rate-Shifting Clips...19 PART I: INPUTS AND OUTPUTS 3 INPUTS 25 Input Tab...25 Jobs and Job Files...26 Loading an Existing Job...27 Upgrading Older Job Files...27 File Input...27 iii

4 RealProducer User s Guide iv Video Source File Size Limit...28 Capture Input...29 Input Duration...29 Audio Mixer...30 Audio Vendor Controls...30 Video Settings...31 Timeline Editor...33 Timeline Editing Controls...34 Source Properties PREFILTERS 37 Audio and Video Preprocessing...37 Controls for Displaying and Enabling Prefilters...38 Audio Level...38 Audio Synchronization...39 Input Cropping...39 Cropping Controls...40 De-Interlace and Inverse-Telecine...41 Inverse-Telecine Prefilter...42 De-Interlace Prefilter...42 Video Noise...43 Low Noise Filtering...44 High Noise Filtering...44 Input Resize...44 Resize Controls...45 Maintain Aspect Ratio...46 High-Quality Resize...46 Black-Level Correction OUTPUTS 47 Output Tab...47 Single Outputs and Multiple Outputs...48 Outputs and Destinations...48 Outputs List...49 Output Selection...50 Output Name...50 Encoding Settings...50 Audience Control Buttons...51 Audience Templates...51 Audience Customization...52 Output File Destination...55 Archive Clips...55 Output File Extension...55

5 Contents Two-Pass Encoding...56 Output File Size...56 Metadata...57 Metadata Buttons...57 Metadata Entry...58 Metadata Titles and Values...58 PART II: ADVANCED AUDIO AND VIDEO SETTINGS 6 AUDIO CUSTOMIZATION 63 Audio Encoding Settings...63 Audio Codec...64 Channels...64 What is Stereo Surround?...65 What is Multichannel Audio?...66 Average Bit Rate...67 Sample Rate...68 What is a Sampling Rate? VIDEO CUSTOMIZATION 69 Video Encoding Settings...69 Video Codec...70 Level...70 Video Average Bit Rate...70 Frame Rate...71 Target Frame Rates...71 Factors that Affect RealVideo Frame Rates...71 Frame Size...72 Maintain Aspect Ratio...73 High-Quality Resize...73 Notes on Resizing...73 Encoding Complexity...75 Frame Rate Mode ADVANCED VIDEO OPTIONS 77 Advanced Video Settings...77 Variable Bit Rate Video...78 VBR Compared to CBR...78 VBR Maximum Bit Rate...79 VBR Target Quality...80 Maximum Video Buffering (Preroll)...81 Maximum Key Frame Interval...82 What is a Key Frame?...82 v

6 RealProducer User s Guide Advantages of Lowering the Maximum Key Frame Interval...82 Costs of Lowering the Maximum Key Frame Time...82 Startup Latency Reduction During Broadcasts...83 PART III: BROADCASTING 9 BROADCAST FEATURES 87 Live Broadcasting...87 Broadcast Trial Runs...88 Types of Broadcasts...88 Helix Push Broadcast...89 Helix Advanced Push Broadcast...91 Helix Multicast Push Broadcast...92 Helix Pull Broadcast...94 Server Broadcast Mode...96 Broadcast Transports...97 Encoder Redundancy...97 Forward Error Correction...98 Error Correction Percentage...99 Redundant Stream Protection...99 FEC Rates and Receiver Buffering...99 Archiving RealProducer Archiving Helix Server Archiving Version 6 IP Addresses SERVER DESTINATIONS 103 Server Destinations Output Servers Buttons Server Destination Templates Helix Push Destination Helix Push Basic Settings Helix Push Advanced Settings Helix Advanced Push Destination Helix Advanced Push Basic Settings Helix Advanced Push Advanced Settings Helix Multicast Push Destination Helix Multicast Push Basic Settings Helix Multicast Push Advanced Settings Helix Pull Destination Helix Pull Basic Settings Helix Pull Advanced Settings vi

7 Contents PART IV: MONITORING 11 JOB MONITORING 125 Monitoring Tab Starting a Job Preview Section Multiple Output Display Audio Meters Clipped Audio Session Logging Session Log Viewer Logging Types Settings Advisor PART V: APPENDIXES A PREFERENCES 133 Preferences File File Location Preferences Template Directories Temporary Directory Log File Preferences Log File Location Logging Settings Log File Rolling Output Preferences Encoding Defaults Output Directory and File Name Defaults Output Server Defaults Metadata Defaults Signal Detection Preferences Audio Watchdog Tests Video Watchdog Tests Message Suppression Frame Analysis Period B AUDIENCE TEMPLATES 145 Predefined Audience Templates Templates Included with RealProducer Customized Templates k Voice k Video k Music vii

8 RealProducer User s Guide 56k Video k Music k Video k Video k Music k Video k Video k Video k Video M Video % VBR Quality Video C AUDIO AND VIDEO TIPS 157 Audio Capture Source Media Recording Equipment Shielded Cables Input Levels Volume Levels for Live Broadcasts Sampling Rates Audio Optimization DC Offset Normalization Dynamics Compression Equalization Video Recording Video Staging Scene Changes and Movement Colors and Lighting Video Output Color Depth Source Media Quality INDEX 163 viii

9 INTRODUCTION This guide explains how to use the graphical application of RealProducer 13.1 to encode on-demand clips and live broadcasts. It describes the file formats and codecs that RealProducer can use to create output. It also explains how to customize audio and video output to meet your viewers needs. For More Information: An additional guide, RealProducer Command Line and Job File Reference, explains how to run RealProducer 13.1 from the command line. It also describes the syntax of the job, audience, and server files used by the graphical application. How This Guide Is Organized The guide contains the following chapters. Chapter 1: Installation This chapter covers RealProducer requirements and installation. Chapter 2: Codecs and File Formats This chapter explains the output file formats and codecs that RealProducer supports. Chapter 3: Inputs As explained in this chapter, you can encode audio and video from a file or live input. Chapter 4: Prefilters By applying prefilters to the input, you can improve the audio and video quality as well as crop and resize a video. 1

10 RealProducer User s Guide Chapter 5: Outputs This chapter explains how to define outputs and select audiences to control how the output is encoded. Chapter 6: Audio Customization In many instances, you ll want to refine the audio settings by customizing an audience definition. Chapter 7: Video Customization You can also customize the video settings of an audience to change, for example, the video codec used to encode the output. Chapter 8: Advanced Video Options This chapter explains advanced video customizations, such as defining the video preroll and creating a variable bit rate clip. Chapter 9: Broadcast Features Refer to this chapter for basic information about broadcasting a live stream. Chapter 10: Server Destinations When you are ready to broadcast a live event, you set up a server destination using the instructions in this chapter. Chapter 11: Job Monitoring This chapter explains how to start, stop, and monitor an encoding job. Appendix A: Preferences This appendix explains how to modify the RealProducer preferences to set overall encoding preferences. Appendix B: Audience Templates Audience templates define encoding settings such as the streaming bit rate. This appendix describes the predefined templates included with RealProducer. Appendix C: Audio and Video Tips Good quality starts at the source. This appendix provides tips for creating high-quality audio and video input. 2

11 Introduction Conventions Used in this Guide The following table explains the typographical conventions used in this guide. Convention emphasis Notational Conventions Meaning Bold text is used for in-line headings, user-interface elements, URLs, and addresses. terminology Italic text is used for technical terms being introduced, and to lend emphasis to generic English words or phrases. syntax This font is used for fragments or complete lines of programming syntax (markup). syntax emphasis Bold syntax character formatting is used for program names, and to emphasize specific syntax elements. variables Italic syntax character formatting denotes variables within fragments or complete lines of syntax. [options] Square brackets indicate values that you may or may not need to use. As a rule, when you use these optional values, you do not include the brackets themselves. choice 1 choice 2 Vertical lines, or pipes, separate values that you can choose between.... Ellipses indicate nonessential information omitted from examples. 3

12 4 RealProducer User s Guide

13 Part I: GETTING STARTED PART I This section explains how to install RealProducer It also covers the file formats and codecs that RealProducer can use when encoding on-demand clips or live broadcasts.

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15 Chapter 1: INSTALLATION CHAPTER 1 This chapter describes the hardware and software requirements for RealProducer. It then explains how to install the product. System Requirements The following table lists the requirements for using RealProducer RealProducer 13.1 System Requirements Hardware or Software Requirement Windows Version Windows XP SP3 Windows Vista Windows 7 Windows Server 2003 Windows Server 2008 Windows.Net runtime.net 2.0 (automatically installed if not present) Windows Installer CPU (minimum) RAM (minimum) Display Resolution version 3.0 (included with Windows XP SP2 and later) Pentium 4 or Core2Duo (recommended) 512 MB 1024x768 pixels or greater Note: When encoding multiple outputs, RealProducer uses each processor core to encode an output. A four-core processor can encode four outputs at the same time, for example. Installing on Windows To install RealProducer, you need a binary installation file that enables the RealProducer features. Note: Your account must have Administrator privileges to install RealProducer. 7

16 RealProducer User s Guide For More Information: See System Requirements on page 7 for computer hardware and software requirements. To install RealProducer onto Windows: 1. Close all running applications. 2. Double-click on the installation program icon. The installer unpacks the required files and opens the installation dialog. 3. Choose the product to install. 4. Read the license and click Accept to agree to its terms. 5. The next page allows you to choose the installation location. The default directory is under C:\Program Files\. You can change this directory by clicking the Browse button and selecting the new path. Note: The installer adds the installation directory to your Windows PATH variable. This allows you to run the commandline application from any directory on your machine. If you do not want to update the PATH value, remove the checkmark from the option. Tip: You must log out of Windows and log back in before a Path variable update takes effect. 6. In the final confirmation screen, verify your choices and click Install. Windows.Net RunTime On Windows, RealProducer installs Microsoft.Net 2.0 SP1 if it is not present already. This installation does not affect other versions of the.net runtime. For example, you can have.net 3.0 and 3.5 installed on the same machine without conflict. Uninstalling the Program Note: If the installer included the.net runtime, you will need to reboot your machine after the installation completes. To remove RealProducer from your machine, use the Add or Remove Programs dialog of the Windows Control Panel. The removal process deletes all files that 8

17 CHAPTER 1: Installation were created by the installer. However, it does not remove any encoded outputs or job files created by RealProducer. 9

18 10 RealProducer User s Guide

19 Chapter 2: CODECS AND FILE FORMATS CHAPTER 2 This chapter explains the input and output formats, audio codecs, and video codecs that you can use with RealProducer. Input Formats When creating content to encode, use uncompressed formats whenever possible. Otherwise, you compress the source once when you digitize it and again when you encode it in a streaming format. This double compression can decrease the image quality. Use a compressed source format only if RealProducer supports the file as input. Uncompressed Input Formats Tip: Always keep copies of the video source files. You cannot convert encoded clips back to their original source formats or transcode them to other streaming formats. You can use the following file formats as input sources on any operating system that runs RealProducer. Using these formats does not require installing other audio and video software: Uncompressed QuickTime 3, 4, and 5 (.mov) WAV audio files (.wav) Uncompressed AVI (.avi) Formats Requiring DirectX You can use the following file formats as inputs on Windows if you have DirectX 9.1 or higher installed: Compressed AVI (.avi) AIFF (.aif,.aifc,.aiff) 11

20 RealProducer User s Guide QuickTime 2 (.mov) MPEG Formats Requiring QuickTime Note: Using MPEG-2 requires the DirectShow MPEG-2 reader. Tip: If you experience problems using MPEG inputs under DirectX, install QuickTime. For More Information: For the latest version of DirectX, go to The following file formats can be used as sources on Windows if the latest version of QuickTime is installed: AU (.au,.snd,.ulw) Sound Designer II (.sd2) DV (.dif,.dv) QuickTime Flattened Movie (.mov,.qt) MPEG For More Information: For more about QuickTime, visit Output Choices RealMedia RealProducer constrains the available audio and video encoding options to values appropriate for the output type. For More Information: See Outputs List on page 49 for information about how you choose the output type. The RealMedia output is a proprietary RealNetworks format. players: Desktop versions of RealPlayer. Mobile devices based on Helix technology. file type: RealMedia (.rm,.ra,.rv,.rmvb) 12

21 CHAPTER 2: Codecs and File Formats audio: RealAudio video: RealVideo multi-rate: yes (see Multi-Rate Streams on page 18) Audio Codec Choices RealAudio The following are the audio codecs that you can choose. Note that all audio codecs encode at discrete bandwidths only. For example, RealAudio stereo music codecs provide 44 Kbps and 64 Kbps choices, but no bandwidths inbetween. For More Information: See Audio Encoding Settings on page 63 for details about how you choose an audio codec and select the audio bit rate. You can use RealAudio as a stand-alone audio format, or as the audio track of a RealVideo clip. audio type: voice, music channels: mono, stereo, stereo-surround, multichannel file types: RealMedia (.rm,.ra,.rmvb) video: RealVideo multi-rate: yes (see Multi-Rate Streams on page 18) The following sections describe the RealAudio codecs available through RealProducer. The codecs are listed in separate tables for voice, mono music, stereo music, stereo surround, and multichannel audio. RealAudio Voice Codecs Voice codecs produce the best results for voice-only audio input. RealAudio Voice Codecs Bandwidth Codec Channels Sampling Rate 5 Kbps RealAudio Voice Kbps RealAudio Voice Kbps RealAudio Voice

22 RealProducer User s Guide RealAudio Voice Codecs (continued) Bandwidth Codec Channels Sampling Rate 16 Kbps RealAudio Voice Kbps RealAudio Voice Kbps RealAudio Voice Tip: The lowest-speed voice codec normally used to encode a RealAudio clip is 16 Kbps. The lower-speed codecs (5, 6.5, and 8.5 Kbps) are used as duress streams when the connection bandwidth drops in a multi-rate clip. They re also used to encode soundtracks for low-bandwidth RealVideo clips. RealAudio High-Response Codecs A high-response codec may have up to twice the range as a normal-response codec. This means it provides crisper sound and captures higher frequencies. High-response codecs are available for mono and stereo encoding. RealAudio High-Response Music Codecs Bandwidth Codec Channels Sampling Rate 20 Kbps RealAudio High Response Kbps RealAudio High Response Kbps RealAudio High Response Kbps RealAudio High Response Kbps RealAudio High Response Tip: A high-response codec may produce more distortion with voices and loud sounds such as drums. If you are encoding music with a diverse range of frequencies, use a high-response codec first. If you notice distortion, compare your results with a clip that uses a normal-response codec. 14

23 CHAPTER 2: Codecs and File Formats RealAudio Mono Music Codecs Use mono music codecs for encoding mono input or stereo input for mono output. RealAudio Mono Music Codecs Bandwidth Codec Channels Sampling Rate 6 Kbps RealAudio Kbps RealAudio Kbps RealAudio Kbps RealAudio Kbps RealAudio Kbps RealAudio Kbps RealAudio Kbps RealAudio RealAudio Stereo Music Codecs Use stereo music codecs for encoding traditional, two-channel stereo music. RealAudio Stereo Music Codecs Bandwidth Codec Channels Sampling Rate 12 Kbps RealAudio Kbps RealAudio Kbps RealAudio Kbps RealAudio Kbps RealAudio Kbps RealAudio Kbps RealAudio AAC Kbps RealAudio Kbps RealAudio AAC Kbps RealAudio AAC Kbps RealAudio AAC Kbps RealAudio AAC Kbps RealAudio AAC Kbps RealAudio AAC

24 RealProducer User s Guide RealAudio Stereo-Surround Codecs Encode your audio using a stereo-surround codec if you know that the source audio is matrixed, multiple-channel sound, and you wish to preserve the multiple channels for your listeners. RealAudio Stereo-Surround Codecs Bandwidth Codec Channels Sampling Rate 44 Kbps RealAudio 2s Kbps RealAudio 2s Kbps RealAudio 2s Kbps RealAudio AAC 2s Kbps RealAudio AAC 2s Kbps RealAudio AAC 2s Kbps RealAudio AAC 2s Kbps RealAudio AAC 2s For More Information: See What is Stereo Surround? on page 65. RealAudio 5.1 Multichannel Audio Codecs Use the multichannel RealAudio codecs if you know that the source audio includes multichannel sound, and your intended listeners have systems able to play all of the channels. RealAudio Multichannel Codecs Bandwidth Codec Channels Sampling Rate 96 Kbps RealAudio Kbps RealAudio Kbps RealAudio Kbps RealAudio For More Information: See What is Multichannel Audio? on page

25 CHAPTER 2: Codecs and File Formats Video Codec Choices RealVideo The following are the video codecs that you can choose. Note that video codecs encode at any bandwidth. For example, if your target bandwidth is 100 Kbps and you choose a 32 Kbps audio codec, the video track automatically encodes at 68 Kbps. For More Information: See Video Encoding Settings on page 69 for details about how to select a video codec. RealProducer encodes RealVideo clips using a RealAudio soundtrack. rate control: constant bit rate (CBR), variable bit rate (VBR) versions: 8, 9, 10 file types: RealMedia (.rm,.rv,.rmvb) audio: RealAudio multi-rate: yes (see Multi-Rate Streams on page 18) RealVideo 10 Codec The RealVideo 10 codec creates the highest quality RealVideo content. It offers improved visual quality over RealVideo 9 and RealVideo 8, especially with fastaction scenes and on-screen text. This is the default RealVideo codec used by RealProducer. Note: Because RealVideo 10 performs more complex analysis of video data than earlier codecs, encoding may take more than twice the time required with RealVideo 9. Use a different RealVideo codec if you need faster encoding performance during broadcasts. RealVideo 9 Codec RealVideo 9 improves on RealVideo 8 with higher compression and improved visual quality. RealOne Player and later can play RealVideo 9 clips. Users who have older versions of RealPlayer are prompted to autoupdate when attempting to play a RealVideo 9 clip. 17

26 RealProducer User s Guide RealVideo 8 Codec The RealVideo 8 codec is compatible with RealPlayer 8 and later. The video quality is not as high as with RealVideo 9 and 10, but encoding is faster. Additionally, RealVideo 8 requires fewer resources on the RealPlayer machine to decompress. This makes it suitable for the slower processors of mobile devices. Multi-Rate Streams With RealMedia output, you can encode an audio-only stream or a video stream for multiple bandwidths. For example, you can create a single RealVideo clip that streams at 56, 128, or 256 Kbps by choosing audiences that encode the same input at different bandwidths. When a viewer requests the clip, Helix Server determines which stream to use based on the available bandwidth, as shown in the following illustration. Clip Encoded for Multiple Bandwidths Note: Each stream that you add to a multi-rate clip increases the clip s file size. Streams for higher bandwidths increase the file size more than streams for lower bandwidth because highbandwidth encodings include more data. Tip: Including multiple audiences in an output increases the processing time needed to encode the stream. This can become a critical issue during live broadcasts because RealProducer must encode all outputs in real-time. When running a 18

27 CHAPTER 2: Codecs and File Formats Rate Shifting broadcast, carefully choose the audiences included in the output. For More Information: The section Audience Templates on page 51 explains how to add multiple audiences to an output. See Live Broadcasting on page 87 for background about running a live broadcast. A rate-shifting clip is a type of multi-rate clip that allows Helix Server to switch between different audience encodings to compensate for network conditions. The following figure illustrates a media session becoming bogged down because of excessive network traffic. Helix Server downshifts to a lowerbandwidth stream to prevent the presentation from stalling. When the congestion clears, Helix Server upshifts to a higher-bandwidth stream. Rate Control During Network Congestion Encoding Requirements for Rate-Shifting Clips The following conditions must exist to enable Helix Server and the media client to shift between audiences during a streaming session: The Helix Server rate control feature must be enabled and configured. For More Information: See Helix Server Administration Guide for information about this feature. 19

28 RealProducer User s Guide The audiences encoded in the clip must be compatible. The following sections explain the requirements for enabling rate shifting when using multiple audiences. Audience Streaming Rates When you create a rate-shifting clip, chose the audience streaming rates carefully. If rates are too close together, the media player may shift rates continuously, which creates a poor user experience. If rates are too far apart, the media player may not be able to shift rates at points where doing so would be advantageous. You may need to experiment with settings until you find audiences that work well for your viewers and your network. To start, follow these principles: Set the top streaming rate to approximately 80 percent of the ideal throughput. To target a 256 Kbps network speed, for example, set the topspeed audience to stream at 200 Kbps. Create a compatible audience that streams at approximately 80 percent of the top-speed audience: 160 Kbps, for example. The media player can shift to this audience if the network throughput slows. Helix Server Oversend Rate When you encode a multi-rate clip or broadcast for rate control, Helix Server allows upshifting to the next higher stream rate only if that rate is no more than a certain percentage above the current rate. This is called the maximum oversend rate. Suppose that the maximum oversend rate is 300 percent. For a clip encoded with 56, 128, and 256 Kbps streams, the media player can upshift through all of the streams because no rate is more than 300 percent of the preceding rate. If the clip contains just 56 and 256 Kbps streams, however, the media player cannot upshift from the 56 Kbps stream. For More Information: The maximum oversend rate is configurable for each Helix Server. For details, refer to the rate control chapters in Helix Server Administration Guide and Helix Server Configuration and Registry Reference. Audio and Video Codecs In a rate-shifting clip, you must encode all video audiences using the same RealVideo codec. For example, you cannot encode one audience with 20

29 CHAPTER 2: Codecs and File Formats RealVideo 8 while encoding another audience with RealVideo 10. Audiences for rate-shifting clips can use different versions of the RealAudio codec, however. Video Frame Size For More Information: See Audio Codec on page 64 for information about audio codec selection. The section Video Codec on page 70 explains video codec selection. Every audience in the output must use the same video frame size to enable the stream to shift bandwidths during streaming. For instance, a video stream cannot shift from a 256 Kbps audience at half-vga dimensions (640x240 pixels) to a 128 Kbps audience at quarter-vga dimensions (320x240 pixels). All Audiences Must Encode Video at the Same Dimensions to Allow Rate Shifting For More Information: See Frame Size on page 72 for an explanation of how to set an output video s dimensions. 21

30 22 RealProducer User s Guide

31 Part I: INPUTS AND OUTPUTS PART I The following chapters explain the basics of how to use RealProducer to select media inputs and define encoded outputs.

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33 Chapter 3: INPUTS CHAPTER 3 The first step for encoding a clip or live broadcast is choosing the input source. This chapter describes how to select a file or live capture device as the input. It also explains how to save your encoding settings to reuse later. Input Tab Click the Input tab to display the controls that allow you to select content and apply prefilter options. Input Tab The controls on the the Input tab allow you to do the following: Start a new job (see Jobs and Job Files on page 26). 25

34 RealProducer User s Guide Select a file to encode (see File Input on page 27). Capture live input (see Capture Input on page 29). Select a portion of a video to encode (see Timeline Editor on page 33). View properties of the input streams (see Source Properties on page 35). Modify the input using prefilters (see Audio and Video Preprocessing on page 37). Note: The settings advisor may also display above the Input tab if RealProducer detects problems with the encoding settings. The section Settings Advisor on page 130 explains this feature. Jobs and Job Files Whenever you use RealProducer, a job records the encoding settings you ve selected. You can view the job syntax at any time by clicking the XML tab. If you save the job to a job file (file extension.rpjf.), you can later use your encoding settings for another clip or broadcast. To save a job file, select File>Save, Ctrl+s, or the Save button on the toolbar. If no job file exists for the job, use the save dialog to choose the job file name and location. You can also choose File>Save Job As to save a modified job file under a new name. If you want to start over, create a new job by selecting File>New, Ctrl+n, or the New button on the toolbar. Warning! Creating a new job resets any encoding information already entered into the graphical interface. Tip: You can create a job file that defines outputs and encoding settings, but no inputs. This allows you to create a library of job profiles to use later. Note: RealProducer provides predefined job files in the samples/jobs subdirectory under the RealProducer main directory. For More Information: For an explanation of the job file syntax, refer to RealProducer Command Line and Job File Reference. 26

35 CHAPTER 3: Inputs Loading an Existing Job To open an existing job file, select File>Open, Ctrl+o, or the Open button on the toolbar. Use the browse dialog to navigate to the job file on your file system. Note the following about reusing a job file: RealProducer records any changes you make to the open job, but does not write the changes into the job file until you save the job. Relative paths in job file values are relative to the directory that holds the job file. Double-check the audience settings for the job to ensure that you are encoding the output properly. For More Information: See Encoding Settings on page 50. A job file can record information specific to a certain clip (metadata). You may need to change this information each time you encode a new clip using an existing job file. Upgrading Older Job Files For More Information: See Metadata on page 57. RealProducer 13.1 uses the job file 3.0 format. The older, version 2.0 job file format used with earlier versions of RealProducer and RealProducer is not compatible with the 3.0 format. However, RealProducer 13.1 automatically updates these older job files to the new 3.0 format. Warning! Once existing job files are updated to the 3.0 format, they are no longer compatible with earlier versions of Helix Mobile Producer and RealProducer. File Input Source files are digitized media files on a hard disk, network, CD, or DVD. To encode output from an existing source, click the File radio button under Input Source on the Input tab. Then click the Open button next to the Input File field to navigate to the file. After a video file loads, the video preview region of the Input tab displays the video s first frame. 27

36 RealProducer User s Guide Input File Video Source File Size Limit Tip: The Input File drop-down records the locations of previous inputs. Click the drop-down arrow to select from these files. For More Information: You can set a video clip s starting and ending points using the timeline editor. See Timeline Editor on page 33. Some computer file systems limit a single file to 2 GB (2048 MB) in size. At a 320-by-240 size and 15 fps, this is about 9.5 minutes of uncompressed, digitized video. Certain video production programs support the OpenDML (AVI 2.0) standard, which allows the creation of files larger than 2 GB. RealProducer may be able to accept a video source file larger than 2 GB as input, depending on the production software used to create the file. If you plan to produce long videos or videos with large dimensions, check whether or not your video production software is limited to a 2 GB output file size. If it is not limited to 2 GB, create a video file larger than 2 GB and test it to determine if RealProducer can accept the file as input. Disk Space Requirements for Video Capture Use the following formula to calculate the approximate size in megabytes of a digitized video file: (pixel width) x (pixel height) x (color bit depth) x (fps) x (duration in seconds) 8,000,000 Suppose you want to capture a three-minute video at 15 frames per second, with 24-bit color, in a window that is 320 by 240 pixels. As you can see from the following equation, your digitized source file would be approximately 622 MB: (320) x (240) x (24) x (15) x (180) / 8,000,000 = 622 Megabytes 28

37 CHAPTER 3: Inputs If necessary, you can conserve disk space by decreasing the clip dimensions or lowering the frame rate, or both. Capture Input To encode live audio or video from a capture card, click the Device radio button under Input Source on the Input tab. Next, select the audio or video device to capture from in the Audio or Video drop-down menu. Input Device Input Duration Tip: If you use a single video capture card to capture both audio and video, choose that card in both the Audio and Video menus. Note: If the video capture card is functioning, the video preview region of the Input tab displays the real-time input. Audio input is not rendered, however. For More Information: If you plan to broadcast the captured input, refer to Live Broadcasting on page 87. The section Video Recording on page 161 provides tips for shooting a video. By default, RealProducer stops encoding the input when the job is stopped manually. Check the Duration box to set a specific point in the stream at which encoding ends. Then enter the time in days (d), hours (h), minutes (m), and seconds (s). Note: This stream duration is measured from the time at which RealProducer starts the encoding process. 29

38 RealProducer User s Guide Audio Mixer To launch your operating system s audio mixer, click and hold the Audio button. Then choose Recording Mixer from the pop-up menu. Audio Mixer Context Menu This opens the recording control window in which you can specify how audio is mixed. Audio Mixer Audio Vendor Controls Note: Audio mixer controls are specific to the sound card and operating system. If you want to adjust the sound recording capabilities of your audio device, click and hold the Audio button. Then choose Vendor-Provided Controls from the pop-up menu. 30

39 CHAPTER 3: Inputs Audio Vendor Control Context Menu This opens the control dialog specific to your audio card and operating system. Audio Control Dialog (Specific to Vendor) Video Settings For More Information: See also Audio Capture on page 157 and Audio Optimization on page 159. To adjust the video recording capabilities, click and hold the Video button next to the video device name. This displays a submenu of available settings dialogs, which can vary with each capture device. Video Vendor Control Context Menu 31

40 RealProducer User s Guide This opens the control dialog specific to your audio card and operating system. Video Control Dialog (Specific to Vendor) Video Capture Dimensions For most video capture cards, you can select the video dimensions in pixels. The input dimensions should be at least as large as the dimensions of your largest output. For More Information: The section Frame Size on page 72 explains the common output dimensions that you can set. Full-Screen Capture A common capture size is 320 pixels wide by 240 pixels high. If you have a fast computer, you can capture full-motion video at the full-screen size of 640 by 480 pixels. Do this only if all of the following are true: Your clips will stream at broadband speeds of 250 Kbps or higher. Your encoded clips will be larger than 320 pixels by 240 pixels. You have a video workstation capable of digitizing full-motion, full-screen video. Consumer-oriented PCs typically cannot handle this large of a load. Cropping and Resizing Whenever possible, capture video at the same dimensions and aspect ratio as your intended outputs. This eliminates the need to crop and resize the video during encoding, which can require significant processing power. If necessary, however, you can crop and resize during the encoding process: 32

41 CHAPTER 3: Inputs The section Input Cropping on page 39 explains how to crop the video input. See Input Resize on page 44 for a description of how to resize the input video. Each output can be resized independently. See Frame Size on page 72 for details. Video Capture Frame Rate For most lower-bandwidth clips and broadcasts, capture at 15 frames per second (fps). This is the maximum, recommended frame rate for outputs lower than 150 Kbps. At speeds higher than 150 Kbps, you can encode up to 30 fps. In these cases, you may want to capture the source input at 30 fps. Timeline Editor After you load an input video file, you can use the timeline editor to set starting and ending points for the encoding job. You can use the timeline editor, for example, to encode only the first minute from a two-minute input file. If you do not make changes using the timeline editor, the entire source file is encoded. Timeline Editor 33

42 RealProducer User s Guide Timeline Editing Controls Tip: The Mark-In and Mark-Out boxes of the File Input section indicate the selected start and stop times in days (d), hours (h), minutes (m), and seconds (s). The Mark-Out time is measured from the input file s normal beginning, not from the Mark-In time. See File Input on page 27. Note: The timeline editor does not play the video or render the audio. The controls on the timeline editor allow you to set the starting and ending points for encoding. The editor displays the timline section to be encoded as a green line. Back to Start. Cick to move the currently displayed position to the input clip s normal starting point. Back 1 Frame. Click to move the currently displayed position back one frame. You can also click the left arrow on the keyboard. Current Position. Shows the position of the frame currently displayed in the editor. Drag to change the displayed frame. Forward 1 Frame. Click to move the currently displayed position forward one frame. You can also click the right arrow on the keyboard. Forward to End. Click to move the currently displayed position to the input clip s normal end. Start Point for Encoding. Drag to set the timeline position where encoding begins. End Point for Encoding. Drag to set the timeline position where encoding ends. Tip: If you open a new video clip as the source, the encoding markers retain their positions unless the new clip is shorter than the selected timespan. Note: RealProducer may adjust the starting and ending points slightly to align them with input video frames. 34

43 CHAPTER 3: Inputs Source Properties After you select an input file or capture device, the Source Properties region of the Input tab displays the input s audio and video properties. Input Properties Information displayed for the source properties includes the following: duration of the input source (file only) name of the input (file only) audio format number of audio channels audio bit depth video format video frame rate in frames per second (fps) video frame size in pixels 35

44 36 RealProducer User s Guide

45 Chapter 4: PREFILTERS CHAPTER 4 Prefilters modify the input stream before it is encoded. They can crop and resize the input as well as improve the audio and video quality. However, some prefilters can significantly increase the encoding time, which may be problematic during a live broadcast. Audio and Video Preprocessing Prefilters appear in the Audio/Video Preprocessing section of the Input tab. All prefilters are optional. Prefilter Settings 37

46 RealProducer User s Guide Controls for Displaying and Enabling Prefilters The following controls appear to the left of each prefilter: Controls Hidden A summary of the prefilter settings (if any) appears to the right. Click to display the full controls. Controls Displayed Click to hide the controls. Prefilter Disabled Any previous settings are retained for this job, but the prefilter will not be used during encoding. Click to enable the prefilter. Prefilter Enabled Click to disable the prefilter. Audio Level The audio level control allows you to set a decibel gain from +12 (amplify the audio) to -12 (attenuate the audio). medium: Audio use: Boost, decrease, or mute the audio input level. impact: Negligible. Safe for broadcasts. To change the audio input level, click and drag the slider control. You can also type a value directly into the text box or click the arrows. Click Mute Input Audio if you want to silence the audio track of a video. Audio Level Controls Tip: A value of 6 doubles the audio level while a value of 12 quadruples it. A value of -6 reduces the level to half, while -12 reduces it to a quarter. Note: When you amplify the audio signal, RealProducer dynamically compresses the audio range if the output signal becomes overmodulated. This way, the output audio is never clipped, even at maximum gain. 38

47 CHAPTER 4: Prefilters Audio Synchronization The audio synchronization prefilter corrects audio shift when audio input is out of synchronization with a video s visual track. medium: Audio use: Shift audio timing to synchronize it with the video track. impact: Negligible. Safe for broadcasts. In the prefilter controls, select Advance or Delay. Then set the number of seconds for the advance or delay by typing the value in the text box or clicking the arrows. Audio Synchronization Controls Tip: Some third-party video editing tools provide information about how much delay exists between audio and video. Input Cropping The cropping prefilter reduces the size of the input by cropping out unwanted portions along the video edges. This can reduce the amount of data encoded and boost clip quality. medium: Video use: Reduce the size of the input by cropping along the video edges. impact: Small. Safe to use with live broadcasts. Tip: If you are encoding a letterbox clip (16:9 aspect ratio) for display on computer screens that use a traditional 4:3 aspect ratio, crop out the black bars at the top and bottom of the video image. This helps to improve the video quality. For More Information: See also Cropping and Resizing to Change Aspect Ratios on page 74 for an example of how to alter an input clip s aspect ratio. 39

48 RealProducer User s Guide Cropping Controls To crop a video, click the Input Cropping box. Input Cropping Controls You can select the cropped area three ways: Click a text box and type the new value manually. Click the arrows beside each text box to select a value. Click and drag the yellow lines in the preview window. Cropping Values The following values appear in the cropping control text boxes. Left Pixels from the left edge where cropping occurs. You can specify up to 32 pixels less than the total width. Top Pixels from the top edge where cropping occurs. You can specify up to 32 pixels less than the total height. Right Pixels from the right edge where cropping occurs. You can specify up to 32 pixels less than the total width. Bottom Pixels from the bottom edge where cropping occurs. You can specify up to 32 pixels less than the total height. Note: If the width or height of the cropped video is not a multiple of 4, the next lower multiple is used. For example, a value of 162 pixels for width or height is adjusted to 160 pixels. Cropping Preview Yellow lines appear on the input preview to indicate the cropped section. You can click and drag a line to set a new cropping position. Click inside the selected area to drag the entire cropping section around the video frame. Areas that will not be encoded are grayed out. 40

49 CHAPTER 4: Prefilters Cropped Video Region De-Interlace and Inverse-Telecine The de-interlace and inverse-telecine prefilters remove artifacts that may occur in videos larger than 320x240 pixels and NTSC-format video transferred from film, respectively. De-Interlace and Inverse-Telecine Controls If you need to use these prefilters, click the Automatic radio button to have RealProducer apply the prefilters only if needed. To use just one of the prefilters, check the Manual button and select the prefilter (one or both) you want. 41

50 RealProducer User s Guide Inverse-Telecine Prefilter Use the inverse-telecine prefilter when encoding NTSC video that was transferred from film and has a frame rate of 30 fps. The prefilter strips out redundant fields, letting RealProducer focus on image quality. medium: NTSC video use: Remove redundant frames. impact: Small. What is Inverse-Telecine? Film is usually shot at 24 frames per second (fps), whereas the NTSC standard for video is 30 fps. The film-to-video conversion (called telecine ) duplicates some fields to increase the frame rate from 24 to 30. American films transferred to video, for example, undergo the telecine process. Applying the inverse-telecine prefilter strips out the redundant frame information, resulting in a higher-quality streaming video. De-Interlace Prefilter Tip: PAL video does not require the inverse-telecine prefilter because the conversion from 24 fps film to 25 fps PAL does not use the telecine process. The de-interlace prefilter removes jaggedness in interlaced NTSC or PAL video. medium: NTSC or PAL video use: Remove jaggedness from video. impact: Small. Not used if the video is less than 240 lines high. Generally safe to leave on for all video input. What is De-Interlacing? A video camera running at 30 frames per second captures the odd-numbered lines of a field in 1/60th of a second and the even-numbered lines in the next 1/60th of a second. It then interlaces the two to create the frame. Because half the field s lines are captured a fraction of a second later than the other half, fast-moving objects may appear jagged. This is the result of the object advancing slightly within 1/60th of a second. 42

51 CHAPTER 4: Prefilters Tip: Typical source video for standard-resolution television is 480 lines high. If you digitize the video with a video capture card that captures at 240 lines high or less, the card throws out either the odd or the even lines, de-interlacing the video during the capture process. De-Interlacing Example The following figure illustrates jaggedness in a detail of an interlaced video. Jaggedness in an Interlaced Video (detail) The next figure shows the jaggedness removed using the de-interlace prefilter. Jaggedness Removed with the De-interlace Prefilter (detail) Video Noise Video noise is a by-product of poor quality in the video production process. The noise reduction prefilter can help reduce this distortion. medium: Video 43

52 RealProducer User s Guide use: Eliminate visual artefacts. impact: Small for Low level. Large for High level (not recommended for broadcasts). Use the drop-down of the noise controls to choose the Low or High level. Video Noise Controls Low Noise Filtering Tip: The source of the noise is typically hardware, such as the video tape, capture card, or camera. Using professional-quality equipment and media helps eliminate video noise at the source. If your source video has high quality, you won t need the noise reduction prefilter. For More Information: See Video Recording on page 161 for tips on creating high-quality source video. If your video input has a small amount of noise, use the Low setting. Because this has a small impact on processing power, the Low noise level is generally safe to leave on for all jobs. It s better practice, though, to use it only when necessary because it may slightly degrade high-quality input video. High Noise Filtering If noise greatly distorts the source video, try the High noise setting. This setting may remove slight details, making highly textured surfaces look more smooth, which may not be desirable in all cases. Warning! The High noise setting can add 30% or more to the encoding time. Input Resize The resizing prefilter allows you to resize the video before you encode it. medium: Video 44

53 CHAPTER 4: Prefilters Resize Controls use: Resize the video dimensions. impact: Small for fast resize. High for high-quality resize (not recommended for broadcasts). Tip: If the input video has a non-square pixel aspect ratio (such as DV), you can use the resizing prefilter to shorten the video horizontally. This converts non-square pixels to square pixels. For More Information: When you encode multiple outputs, you can set the video dimensions for each output separately. See Frame Size on page 72. Use the resize controls to specify predefined or customized video dimensions. The video preview window on the Input tab indicates the new video size. Resize Controls In the drop-down, you can set one of the following values (WidthxHeight in pixels): Custom Set pixel width and height using the Width and Height menus. 128x96 (SQCIF) Sub-Quarter Common Intermediate Format. 176x144 (QCIF) Quarter Common Intermediate Format. 352x288 (CIF) Common Intermediate Format. 640x240 (HVGA) Half VGA. 320x240 (QVGA) Quarter VGA. Note: The minimum size for a resized video is 32-by-32 pixels. The width and height must be multiples of 4, such as 160 pixels, 240 pixels, and so on. Tip: If you plan to create multiple outputs at different sizes, set the input size to the largest output size. Then scale other 45

54 RealProducer User s Guide Maintain Aspect Ratio outputs smaller as needed. The section Frame Size on page 72 explains how to resize a specific output. When the Maintain Aspect Ratio box is checked, you can enter just the height or width value for the resize. RealProducer automatically calculates the other value to maintain the ratio between the two dimensions. By unchecking this box, you can enter width and height values independently. High-Quality Resize Warning! If you do not maintain the aspect ratio, the output may appear distorted. Selecting a high-quality resize results in a superior image. However, it may double or triple the encoding time because it carefully analyzes the video source before resizing. Warning! Because of its potentially high impact on encoding performance, the high-quality resize prefilter is not recommended for live broadcasts. Black-Level Correction Black-level correction improves a video s contrast by making near-black pixels pure black and near-white pixels pure white. This improves the video s appearance if it looks washed out because of a lack of contrast. medium: Video use: Improve visual contrast. impact: Small. Generally safe to leave on for all video input. Note: You need only to enable the black-level prefilter to use it. It has no other controls. Tip: Applying this prefilter to the input can improve codec efficiency by increasing the number of pixels that have the same color value, allowing for greater compression. 46

55 Chapter 5: OUTPUTS CHAPTER 5 Output options allow you to configure encoding settings and send the stream to a file, a broadcast server, or both. Output Tab Click the Output tab to display the controls that allow you to define your encoding outputs and destinations. Output Tab The controls on the Output tab allow you to do the following: Set up one or more outputs (see Outputs List on page 49). Define encoding settings for each output using audiences (see Encoding Settings on page 50). Save each output to a file (see Output File Destination on page 55). 47

56 RealProducer User s Guide Deliver an output stream to a broadcast server (see Server Destinations on page 103). Add clip information to each output (see Metadata on page 57). Note: The settings advisor may also display above the Output tab if RealProducer detects problems with the encoding settings. The section Settings Advisor on page 130 explains this feature. Single Outputs and Multiple Outputs Each output defines a set of encoding options such as the file type and which audio and video codecs are used. One output may suit all of your target media players. However, you can also define multiple outputs. For example, you might use one output to encode the input at 320x240 pixels using the RealVideo 10 video codec. Another output can encode the same input at 176x132 pixels using the RealVideo 8 video codec. Outputs and Destinations Note: Each output you add to a job increases the processing time required during encoding. The data for each output is delivered to at least one destination. There are two types of destinations: a file destination and a broadcast server destination. For example, to broadcast a live event while simultaneously writing the stream to an archive file, you set up both a server destination and a file destination. For each encoding job, RealProducer can encode one or more outputs, and each output can have one or more destinations. 48

57 CHAPTER 5: Outputs Multiple Outputs Written to Multiple Destinations Tip: Outputs define what you are encoding. That is, the output sets the file type, screen size, streaming bit rate, and codecs used. A destination defines where the output is delivered, either to a file or to a broadcast server. For More Information: See Output File Destination on page 55 and Server Destinations on page 103. Outputs List For each encoding job, you define at least one output by adding the output to the Outputs List. Outputs List 49

58 RealProducer User s Guide You add and delete outputs from the job using the buttons at the top of the Outputs List: Add a new output to the Outputs List. Delete the selected output. Output Selection Clicking the Add button RealMedia output. displays a menu allows you to choose a new Output Name Note: The other sections on the Output tab display the information only for the selected output. You can select and edit only one output at a time. When you encode the job, however, all outputs are encoded simultaneously. When you add an output, RealProducer creates a default name for the output in the Outputs List. Change the name by clicking the default name in the Outputs List and entering a new name. Note: Output names are for your convenience in identifying the output. They do not affect the encoding process. Choose names that clearly identify each output s intended viewers. Encoding Settings In the Encoding Settings section of the Output tab, you set the basic encoding parameters by adding one or more audiences to the selected output. Encoding Settings Section (Multi-Rate RealVideo Clip) 50

59 CHAPTER 5: Outputs Audience Control Buttons Note: If you are encoding multiple outputs, highlight the correct output in the Outputs List before choosing an audience. You can add audiences to one output at a time. The buttons to the right of the Encoding Settings section allow you to manage the audience templates that define the output s encoding parameters: Add an audience template to the selected output. Edit the encoding settings for the selected audience. Save As a new audience template. Delete the selected audience from the output. Audience Templates Each audience defines a set of encoding parameters, such as the streaming bit rate and the codecs used to compress the stream. Click the Add button to add an audience to the output. The pop-up dialog displays the available audience templates. Audience Template Pop-Up 51

60 RealProducer User s Guide Select the audience name and click Add to Job. The Encoding Settings section then displays the audience, listing its encoding properties. Tip: Using the preferences, you can select audiences that are used automatically whenever you create an output. See Output Preferences on page 138. For More Information: The section Predefined Audience Templates on page 145 lists the properties of the predefined audience templates included with RealProducer. Multiple Audiences for Multi-Rate Clips A RealMedia output can include multiple audiences to create a multi-rate streaming clip or broadcast. To select more than one audience, hold down the Ctrl key and click the audience names. You can also add each audience to the output one at a time. Tip: Including multiple audiences in a clip intended solely for downloading increases the file size unnecessarily and does not improve the playback quality. For More Information: For background on using multiple audiences to enable rate shifting during streaming, refer to Multi-Rate Streams on page 18. Name Matching You can filter the templates shown in the audiences pop-up by typing a text string in the Where name matches field. Only audience names that contain the text then display. For example, enter 80 to show the audiences designed to stream at 80 Kbps. Audience Customization Tip: Text matching is not case sensitive. In many cases, you may need to modify the settings for an audience added to an output. For instance, you may want to increase the streaming bandwidth, or encode a soundtrack using a different audio codec. To modify an audience, highlight the audience name in the Encoding Settings section and click the Edit button. This displays the Encoding Settings pop-up. 52

61 CHAPTER 5: Outputs Audience Encoding Settings Pop-Up Audience Properties In the Encoding Settings pop-up, you can change the following values: The template name in the Name field. Audio options such as the audio codec, audio bit rate, and output sampling rate. (See Audio Encoding Settings on page 63.) Video options such as the video codec, video bit rate, and output clip dimensions. (See Video Encoding Settings on page 69.) Advanced video options such as the maximum preroll and the use of variable bit rate (VBR) encoding. (See Advanced Video Settings on page 77.) Template Creation Customizing an audience s properties applies the changes to the current job only. It does not modify the original audience template. To preserve the customizations so that you can apply them quickly to other jobs, highlight the audience name in the Encoding Settings list. Then click the Save As button. 53

62 RealProducer User s Guide Save Audience Template In the Save as Template pop-up, do one of the following: To update the original template with the new settings, click Save and confirm that you want to replace the existing template. To create a new template, enter a new name in the Template Name field. Then click Save. Template Deletion Tip: If you already entered a new name in the Name field of the Encoding Settings pop-up, RealProducer prompts you to save the template under that name. Note: Templates are stored in the audiences subdirectory of the RealProducer installation directory using the template name along with the file extension.rpad. For More Information: For more about audience file syntax, refer to RealProducer Command Line and Job File Reference. Do the following to delete an audience template permanently: 1. Click the Add button in the Encoding Settings section of the Output tab to display the audience template pop-up (see Audience Templates on page 51). 2. In the list of templates, select the audience that you want to delete. 3. Click the Delete button on the right side of the audience pop-up. 4. Confirm the deletion. Tip: If the audience is still included in the output, highlight the template name in the Encoding Settings list and click the Delete button. This removes the audience settings from the job. 54

63 CHAPTER 5: Outputs Output File Destination Output File Section In the Output File section, you can create a file destination for the selected output. Click the Open button to navigate to a location on the file system where you want to write the file. Enter a file name, then click Save in the dialog. Archive Clips To the right of the file destination section, the Avail Space on Disk field indicates the free space in Gigabytes on the selected disk. Tip: Using the preferences, you can select a clip name that is used automatically whenever you create a file destination. See Output Preferences on page 138. Note: With RealMedia clips, the options for progressive download and stream hinting are always enabled. For More Information: You can send live input to a server for broadcast while simultaneously writing it to a file for archive purposes. The data sent to each destination is identical. See Server Destinations on page 103. When setting the output file name, you can quickly select the output directory and file name of a previous file by clicking the file name drop-down arrow. RealProducer does not overwrite the previous clip if it still exists. Instead, it archives the existing clip by appending _archnnn to the base file name. For example, movie.rm becomes movie_arch001.rm before the new movie.rm clip is saved. If you encode the output again, the existing movie.rm becomes movie_arch002.rm. Higher numbers therefore represent newer archives. Output File Extension The output file extension depends on the output type (see Output Selection on page 50). RealMedia CBR clips use the.rm extension. RealMedia VBR clips 55

64 RealProducer User s Guide typically use the extension.rmvb. Mobile media players may not recognize the.rmvb extensions, however. In this case, encode VBR output using the.rm extension. Two-Pass Encoding When the Two Pass option is enabled, RealProducer runs through the entire source clip once to gather information about the source stream. In the second pass, it performs the actual encoding. Two-pass encoding can substantially increase clip quality, especially for VBR clips, but it requires more encoding time. Tip: Use two-pass encoding whenever you encode from a digitized file. Turn it off only if you must decrease the encoding time. Note: Two-pass encoding cannot be used during live broadcasts. It is automatically disabled if you add a server destination to the output. For More Information: For more about VBR encoding, refer to Variable Bit Rate Video on page 78. Output File Size An encoded, compressed clip is often smaller than the input file. This means that file size limits imposed by an operating system s file system are generally more of a problem when capturing video than when encoding it. However, there are some cases in which an output clip may exceed the operating system s maximum: A clip encoded for multiple bandwidths (especially with multiple, highspeed audiences) may exceed the source clip in size, even though each stream contains less data than the original input. If you encode a long video clip directly from a live source or capture device, the encoded clip may grow larger than the allowable file system limit. For More Information: See Disk Space Requirements for Video Capture on page

65 CHAPTER 5: Outputs RealMedia File Rolling When a RealMedia clip reaches the operating system s file size limit, RealProducer automatically creates, or rolls, a new clip. The new clip has the same name as the original clip, but with a number added to the file name. For example, movie.rm rolls to movie1.rm when movie.rm reaches the operating system limit. The clip movie1.rm rolls to movie2.rm if it grows too large, and so on. For More Information: By using the command-line application or editing a job file, you can set lower limits on file rolling. You can also roll files by time, such as every 15 minutes. For details, refer to RealProducer Command Line and Job File Reference. Metadata RealProducer can encode metadata such as title, author, and copyright directly into an output stream. To define metadata for an output, highlight the output in the Outputs List. Then use the controls in the Metadata section. Metadata Section Metadata Buttons Use the buttons to the right of the Metadata section to define the selected output s metadata values: Add a metadata entry to the output. Edit the selected metadata value in a pop-up. You can also double-click the metadata line to display the pop-up. Copy the selected metadata value to a different output. Click the button, then use the context menu to select a specific output or all outputs. Delete the selected metadata entry. 57

66 RealProducer User s Guide Metadata Entry Tip: Using the preferences, you can select metadata values that are used automatically whenever you create an output. See Output Preferences on page 138. You add or edit metadata values in the Edit Metadata pop-up. When you add a value, select the type of metadata in the Name pull-down. Then enter the metadata value in the Value field. When you edit a value, you can change only the Value setting. Edit Metadata Pop-Up Metadata Titles and Values Tip: When adding or editing metadata, you can quickly choose a previous value for the selected metadata type by clicking the Value field drop-down arrow. The following sections list the acceptable metadata values. Title Short title of the content. Author The name of the person or organization that created the content. Copyright The copyright string, such as: (c) 2009 XYZ Corporation 58

67 CHAPTER 5: Outputs Keywords Words that search engines can read to categorize the clip. Add a few words, separated by spaces, that will help your audience search for your clip. Description Tip: Unless you are adding a proper name, use lowercase for each term. Avoid overly generic terms such as video or music. Description of the content that appears when the viewer displays extended clip information. This value is used to provide detail too long for the title. Rating Criteria (RealMedia) A ratings value that indicates content suitability for different age groups. The values vary depending on the ratings entity. RealMedia Ratings Criteria RealPlayer uses the following ratings values to indicate content suitability for different age groups: No Rating (default) All Ages Older Children Younger Teens Older Teens (15 and up) Adult Supervision Recommended Adults Only 59

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69 Part II: ADVANCED AUDIO AND VIDEO SETTINGS PART II The chapters in this section explain how to customize audio and video settings to tailor outputs to your specific needs.

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71 Chapter 6: AUDIO CUSTOMIZATION CHAPTER 6 Using the audio customization options, you can modify the audio encoding properties of an audience. You can select the audio codec, bit rate, and sampling rate. Audio Encoding Settings You customize audio by selecting the audience in the Encoding Settings section of the Output tab, then clicking the Edit button. The Audio section of the audience pop-up displays the audio editing options. Audio Encoding Settings Note: If you are working with a multi-rate output, you can customize the audio settings for only one audience at a time. For More Information: See Audience Customization on page

72 RealProducer User s Guide Audio Codec The Codec drop-down allows you to choose a specific type of codec for audio encoding. use: Select the audio codec. restrictions: Output type restricts the available codecs (see Output Selection on page 50). All audiences for a rate-shifting clip must use the same audio codec. Choices include the following: None Do not encode audio. RealAudio Voice Voice. See RealAudio Voice Codecs on page 13. RealAudio High Response Mono or stereo music. See RealAudio High- Response Codecs on page 14. RealAudio Mono, stereo, stereo surround, or multichannel music. See: RealAudio Mono Music Codecs on page 15. RealAudio Stereo Music Codecs on page 15. RealAudio Stereo-Surround Codecs on page 16. RealAudio 5.1 Multichannel Audio Codecs on page 16. RealAudio AAC Stereo or stereo surround music. See: RealAudio Stereo Music Codecs on page 15. RealAudio Stereo-Surround Codecs on page 16. Channels The Channels drop-down sets the number of audio channels encoded. use: Select the number of channels encoded. restrictions: Codec choice affects the number of channels that may be encoded. Choices, which depend on the chosen codec s capabilities, may include the following: Mono Stereo Stereo Surround 64

73 CHAPTER 6: Audio Customization 5.1 Multichannel What is Stereo Surround? Stereo surround audio includes additional channels that are mixed (or matrixed) using the conventional left and right stereo channels. The extra channels can be played using a stereo-surround receiver. However, stereo surround is compatible with any stereo receiver. If the receiver cannot extract the data for the extra channels, it plays just the stereo left and right channels. For More Information: You can find additional information about stereo surround input at or Stereo Surround Channel Arrangements The following table explains the common channel arrangements found in matrixed, stereo surround audio. Common Channel Arrangements in Matrixed, Stereo Surround Audio Channels Description 4 To the standard left and right channels, this arrangement adds a front center and a rear center channel. 5.1 This type of matrixing uses five main channels: left, center, right, left surround, and right surround. The.1 refers to a sixth, low-frequency effects (LFE) bass channel that covers a fraction of the frequency range of the main channels. 6.1 Building on the 5.1 arrangement, this type of matrixing adds two additional channels for playback on two additional speakers. 7.1 Also building on the 5.1 arrangement, this type of matrixing adds four additional channels for playback on two additional speakers. When to Use a Stereo-Surround Codec Stereo surround is suitable for high-bandwidth streaming or download audiences listening on more than two speaker channels (home theater, for example). You should encode your audio using a stereo-surround codec if all of the following are true: The source audio is matrixed, multiple-channel sound. (These sources are prevalent on DVDs and television broadcasts.) 65

74 RealProducer User s Guide At least some of your listeners will play the output on systems that have more than two speaker channels. You are targeting a high-bandwidth streaming or download audience. Tip: Because the multi-channel input of stereo surround is actually encoded as standard stereo input, the computer running RealProducer does not require a special sound card or cabling. When Not to Use a Stereo-Surround Codec Encode your audio using a standard stereo codec if any of the following are true: The input is standard stereo (left and right channels with no additional, matrixed channels). Note: Although you can encode standard stereo input using a stereo-surround codec, there are no advantages to doing so. RealProducer does not create the extra channels. It only preserves existing channels. Additionally, standard stereo codecs are more efficient than stereo-surround codecs at encoding two-channel audio. Your audience will play the stream on systems that includes only the stereo left and right channels. You wish to stream the audio at a bandwidth lower than those available with stereo-surround codecs. What is Multichannel Audio? Tip: When you create a SureStream RealAudio clip, you can encode low-bandwidth streams in conventional stereo, and high-bandwidth streams that preserve the stereo surround audio. Multichannel audio includes channels in addition to the left and right stereo channels. Unlike stereo surround, however, multichannel audio encodes the additional channels separately. Multichannel audio is suitable for highbandwidth streaming or download audiences listening on more than two speaker channels (home theater, for example). 66

75 CHAPTER 6: Audio Customization Tip: Multichannel audio is often called discrete multichannel, whereas stereo surround is called matrixed multichannel. The quadraphonic multichannel format, which uses two front and two back channels, is obsolete and not supported by RealProducer. Sounds Cards for Multichannel Audio Input To enable discrete, multichannel audio, your sound system must capture and preserve each channel. For live capture, the sound card on the RealProducer computer must support the multiple input channels. A standard sound card supporting only two-channel stereo input cannot capture multichannel audio. Tip: A common audio format to use with multichannel audio is AC-3, which is also called Dolby Digital. Channels Encoded by RealProducer RealProducer encodes all multichannel output as 5.1 channels (left, center, right, left surround, right surround, LFE bass) or 6 channels. It can accept fewer than six channels as input, upmixing as necessary to create the additional channels. Multi-Rate Clips with Standard Stereo for Low Bandwidths When encoding a SureStream RealAudio clip, you can encode multichannel audio at high bandwidths and standard stereo at low bit rates. Do not encode standard stereo input with the multichannel codecs, however, as the quality will not be as high as when you use standard stereo codecs. Average Bit Rate In the Avg. Bitrate field, use the drop-down to select the bit rate for the audio stream. use: Set the audio stream bit rate. restrictions: Codec and channels settings affect possible choices. For More Information: See Audio Codec Choices on page

76 RealProducer User s Guide Sample Rate The Sample Rate field indicates the sampling rate of the output. RealAudio codecs support just one sampling rate. use: Indicate the audio output sampling rate. restrictions: none What is a Sampling Rate? An audio sampling rate indicates the number of samples taken every second when the analog audio signal was digitized. Input audio from a file or audio capture card has a specific sampling rate, typically within the range of 8,000 to 48,000 Hz. Each audio codec also has an optimal sampling rate (or rates). If the input audio s sampling rate does not mach the codec s required rate, RealProducer resamples the input. This changes the sampling rate to that required by the codec without causing pitch shifting. For best results, the audio input sampling rate should be equal to or greater than the codec s rate. For rate-shifting clips, the input sampling rate should be equal to or greater than the highest overall sampling rate used. This is typically the sampling rate used by the highest-bandwidth audience chosen. Tip: During a live broadcast, it is helpful to avoid resampling by ensuring that your audio input uses a preferred sampling rate of the output. For More Information: The audio properties, which are described in Source Properties on page 35, display the input sampling rate. The section Audio Codec Choices on page 13 lists the optimal sampling rate for each audio codec. 68

77 Chapter 7: VIDEO CUSTOMIZATION CHAPTER 7 Video customizations allow you to modify the video encoding properties of an audience. For example, you can select the video codec, the bit rate, and the frame rate. You can also scale the output video smaller than the input video. Video Encoding Settings You customize video settings by selecting the audience in the Encoding Settings section of the Output tab, then clicking the Edit button. The Video section of the audience pop-up displays the video editing options. Video Encoding Settings Note: If you are working with a multi-rate output, you can customize the video settings for just one audience at a time. 69

78 RealProducer User s Guide For More Information: See Audience Customization on page 52. Video Codec The Codec drop-down sets the video codec used. use: Choose the video codec. restrictions: All audiences for a rate-shifting clip must use the same codec. For standards-based codecs, the profile is included with the codec name. Select one of the following: None Do not encode video. RealVideo 8 See RealVideo 8 Codec on page 18. RealVideo 9 See RealVideo 9 Codec on page 17. RealVideo 10 See RealVideo 10 Codec on page 17. Level The Level drop-down is not functional for RealVideo content. Video Average Bit Rate For the Avg. Bitrate option, use the arrows to select the average bit rate for the video stream in Kilobits per second (Kbps). use: Set the video stream average bit rate. restrictions: None. Tip: The total bit rate for the audience equals the audio bit rate plus the video bit rate: Total Bit Rate = Audio Bit Rate + Video Bit Rate. 70

79 CHAPTER 7: Video Customization Frame Rate Use the arrows of the Frame Rate option to set the maximum frame rate for the video stream. use: Set the video maximum frame rate. restrictions: Output frame rate will not exceed the input frame rate (see Source Properties on page 35). Target Frame Rates The higher the frame rate, the smoother the motion in the video. 24 to 30 Frames Per Second The standard frame rate for full-motion video is 24 to 30 fps. At this speed, the human eye perceives movement as continuous a phenomenon known as persistence of vision. Tip: RealNetworks recommends using a rate of 30 fps only for download clips or if streaming bandwidth is at least 250 Kbps. 15 Frames Per Second This is a common frame rate target for video that streams at less than 250 Kbps. To most people, a 15 fps video appears to flow relatively smoothly. Below 15 Frames Per Second You can set a frame rate target below 15 fps for lower-bandwidth settings. Below 7 fps, the video will look very jerky. Below 3 fps, a video essentially becomes a slideshow. Tip: Devices with slow processors may have trouble decoding video with a high frame rate. For these devices, you may want to choose a slower maximum rate, such as 7.5 fps, even if the available bandwidth supports a higher frame rate. Factors that Affect RealVideo Frame Rates For RealVideo output, the frame rate field sets only the maximum frame rate. The actual frame rate for an encoded video varies throughout the clip. Several factors affect how the encoded frame rate of the RealVideo output. 71

80 RealProducer User s Guide Video Dimensions The video s dimensions greatly affect frame rate. If the dimensions are too large for your target bandwidth, you will not get a high frame rate. Tip: To get a higher frame rate, reduce the output video dimensions as described in Frame Size on page 72. Codec Choice RealVideo 10 generally provides a frame rate faster than that produced by older RealVideo codecs. Tip: RealVideo has an option for smoother motion. At lower bandwidths, this helps to raise the clip s overall frame rate. See Frame Rate Mode on page 76. Two-Pass Encoding Using this option helps RealProducer analyze the input better and produce the highest frame rate possible. For More Information: See Two-Pass Encoding on page 56. Variable Bit-Rate Encoding In a video that has a mix of fast and slow scenes, VBR encoding helps the fast scenes achieve a higher frame rate. For More Information: See Variable Bit Rate Video on page 78. Frame Size By default, the encoded video has the same dimensions as the video input. To change the size of the output, use the Frame Size controls. use: Change the output video dimensions. restrictions: For a multi-rate RealMedia clip, all audiences must encode video output at the same frame size. 72

81 CHAPTER 7: Video Customization Frame Size Controls In the Frame Size drop-down, you can set one of the following values (WidthxHeight in pixels): No Resize Keep output size the same as input size. Custom Set pixel width and height using the WxH text fields. 176x144 (QCIF) Quarter Common Intermediate Format. 352x288 (CIF) Common Intermediate Format. 640x240 (HVGA) Half VGA. 320x240 (QVGA) Quarter VGA. Maintain Aspect Ratio If you check the Maintain Aspect Ratio box, you can enter just the height or width value for the resize. RealProducer automatically calculates the other value to maintain the ratio between the two dimensions. By unchecking this box, you can enter width and height values independently. High-Quality Resize Warning! If you do not maintain the aspect ratio, the output may appear distorted. Selecting the Use High Quality Resize option produces superior results, but increases the encoding time. Uncheck the box if you need to decrease the encoding time, such as during a live broadcast. Note that the video quality will decline, however. Notes on Resizing Note the following when resizing video output. Methods of Resizing There are three methods of resizing available: 73

82 RealProducer User s Guide capture card When capturing live input, use the video capture card to set the video input to the same dimensions as the largest output size. This is generally faster than resizing input through software. resizing prefilter The resizing prefilter (see Input Resize on page 44) resizes the input, whether a live capture or a prerecorded file, before it is encoded. If you want all of your outputs to be the same size, resize the input using this prefilter. video output If you are encoding multiple outputs at different dimensions, define each dimension in the video settings of each output. Cropping and Resizing to Change Aspect Ratios Often, a source video is captured at a 4:3 aspect ratio, but must be encoded for a mobile device that uses a different aspect ratio. To change the aspect ratio without distorting the output, follow these steps: Use the input cropping prefilter (see Input Cropping on page 39) to crop the video to the device s screen aspect ratio. Resize the output to the device s screen size while maintaining the aspect ratio. Cropping and Resizing Example The following figure illustrates a 320x240 input video cropped to 292x240, then resized to 176x144. Video Cropped and Resized 74

83 CHAPTER 7: Video Customization Desktop Video Dimensions Most desktop videos use the 4:3 aspect ratio of standard computer monitors or the 16:9 aspect ratio of widescreen monitors. The following table provides size recommendations based on bandwidth. Recommended Video Dimensions Bandwidth Pixel Dimensions (4:3) Pixel Dimensions (16:9) less than 256 Kbps 176x132; 240x x108; 256x to 512 Kbps 320x240; 448x x180; 512x Kbps or higher 448x336; 640x x432; 1280x720 Note: At larger dimensions such as 640x480, the input video should be of very high quality. Encoding Complexity The encoding complexity affects how the codec analyzes the input before encoding it. The higher the complexity, the better the quality of the output. use: Determines how complexly the codec encodes the output. restrictions: Higher complexities require more processing time. In the Encoding Complexity drop-down, select one of the following complexity modes: Very Low (Fastest) Low (Faster) Medium High (Slower) Very High (Slowest) Tip: The terms Fastest, Faster, Slower, and Slowest refer to the relative speeds of the encoding process that you can expect when you choose one of these complexity levels. Note: For RealVideo, Very Low and Low are equivalent settings. As well, the High and Very High settings produce the same results. 75

84 RealProducer User s Guide Frame Rate Mode The Frame Rate Mode option affects how the RealVideo codec encodes scenes when available bandwidth is tight. use: Emphasize smooth motion or picture clarity. restrictions: Primarily affects low-bandwidth encodings. In the drop-down, choose one of the following: Sharp Focus on image quality, sacrificing smooth motion by lowering the frame rate if necessary. Normal Compromise between image quality and smooth motion. Smooth Keep the frame rate as high as possible, sacrificing image clarity as necessary. Slideshow Encode as a slideshow of still frames. Tip: A slideshow is recommended only for very large videos encoded for very low bandwidths. It is better practice, however, to resize the video to dimensions appropriate for you target audience. 76

85 Chapter 8: ADVANCED VIDEO OPTIONS CHAPTER 8 Using advanced video options, you can create a variable bit rate (VBR) clip for download or streaming. You can also modify the stream preroll and video key frame interval. Advanced Video Settings You can set advanced video options by selecting the audience in the Encoding Settings section of the Output tab, then clicking the Edit button. The Advanced Video Settings section of the audience pop-up displays the available options. Advanced Video Encoding Settings Note: If you are working with a multi-rate output, you can customize the advanced video settings for only one audience at a time. 77

86 RealProducer User s Guide For More Information: See Audience Customization on page 52. Variable Bit Rate Video Click Perform Variable Bit Rate Encoding to create a VBR clip. If this option is not used, the output is a CBR clip that can have one or more audiences. use: Create a download or streaming clip that can exceed the average bandwidth setting. restrictions: Only one audience for each VBR output. VBR Compared to CBR Tip: Two-pass encoding is an important component for creating a high-quality VBR clip. For more information, refer to Two-Pass Encoding on page 56. A video clip streams at either a constant or a variable bit rate: CBR (Constant Bit Rate) CBR encoding is the traditional mode for streaming video. You should generally use CBR video when streaming at bandwidths below 350 Kbps, or anytime you want to create a rate-shifting clip. VBR (Variable Bit Rate) VBR encoding gives more bandwidth to scenes that are hard to compress, making the most visible difference in videos that have fast-moving, highaction scenes. VBR encoding is well-suited for the following circumstances: High-quality download clips. Streaming at bandwidths of 350 Kbps or higher with no rate shifting. VBR encoding is not suited for the following situations: Live broadcasts. Streaming at bandwidths below 350 Kbps. Encoding a multi-rate clip that allows rate shifting. 78

87 CHAPTER 8: Advanced Video Options Networks Suitable for VBR Streaming To accommodate VBR, the streaming network must be able to handle the bandwidth spikes inherent in VBR encoding. The following types of audience networks are good candidates for VBR streaming: Local area networks (LANs) such as a corporate network. Cable modem users Because all viewers in these networks share a large pool of bandwidth, a VBR clip s intermittent bandwidth spikes tend not to overload a single viewer s connection bandwidth. Networks Less Suitable for VBR Streaming Connections in which bandwidth is not shared, such as DSL, can prove problematic for VBR streaming. A 450 Kbps VBR clip may have a maximum bandwidth of 900 Kbps, for instance. If a DSL connection has a maximum throughput of 500 Kbps, the VBR clip may stall. Broadcasting VBR Clips If you broadcast variable bit rate (VBR) video, your outgoing RealProducer bandwidth as well as your viewers network connections should be able to handle the maximum bandwidth requirement for your selected audience. Note, however, that when you broadcast a VBR stream, bandwidth spikes occur for each viewer at the same time. When broadcasting VBR, therefore, your network needs to handle higher cumulative spikes than when you stream prerecorded clips. VBR Maximum Bit Rate Tip: Multicast delivery, which is available on some intranets, helps to overcome bandwidth spikes by delivering one stream to all viewers, rather than a separate stream to each viewer. For more information, refer to the multicasting chapter of Helix Server Administration Guide. The value of the Max Bitrate field caps the bandwidth that the VBR clip can consume. This determines the highest value that the streaming bit rate can reach. The maximum rate may occur during specific passages, such as highaction sequences, to improve video clarity. 79

88 RealProducer User s Guide Relationship to Average Bit Rate Through most of a VBR video, the second-by-second bandwidth use is close to the video s average bit rate value. For example, a VBR clip may average 450 Kilobits of data per second. However, if the VBR audience defines a maximum bit rate of 900 Kbps, the stream can, if necessary, consume up to 900 Kilobits of data a second. Tip: As you encode VBR clips for download, you can consider the average bit rate as a guide to quality and file size. For example, a 450 Kbps VBR download will generally have lower quality and a smaller file size than a 750 Kbps VBR download. For More Information: See Video Average Bit Rate on page 70. Maximum Bit Rate Value The maximum bit rate is typically 50 to 100 percent higher than the video s average bit rate. Although you can set the maximum bit rate value higher or lower, a higher setting is unlikely to result in significantly greater quality. You can lower the setting if you want to reduce the bandwidth spikes on your network, however. VBR Target Quality Tip: Lowering the maximum rate below 50 percent decreases the benefits of VBR encoding. The closer the maximum rate approaches the average rate, the more the clip behaves like a CBR clip. The Target Quality setting gears the encoding process to achieve a certain level of visual quality. With a quality of 100 percent, for example, RealProducer attempts to reproduce the visual quality of the input nearly perfectly. A lower quality, such as 90 or 80 percent, allows for more visual imperfections but results in a smaller clip that uses less bandwidth. Note: A quality setting does not guarantee perfectly faithful reproduction of the input. It merely attempts to achieve the quality level within the input constraints, such as the video dimensions, frame rate, and bit rate. 80

89 CHAPTER 8: Advanced Video Options Relationship to Average Bit Rate Because encoding for quality can vary the average bit rate greatly, the average bit rate setting is ignored. That is, the average bit rate and quality settings are mutually exclusive, and you can define only one of the values. Quality-Based Encoding Example If you set a maximum bit rate of 900 Kbps and a quality of 100 percent, for example, the average bit rate may turn out to be close to 900 Kbps. At a lower quality target, such as 80 percent, the average bit rate will probably be lower. The actual, average bit rate depends greatly on content, though, and will vary for each clip. Streaming Quality-Based VBR Clips Because their average bit rate can vary greatly, quality-based VBR clips are better suited for downloading than streaming. However, you can stream a quality-encoded stream as long as your network has the capacity to provide to each user the bandwidth indicated by the maximum bandwidth target. Typically, each stream will use less bandwidth than this. Note: You can compute the average bandwidth of a clip by dividing the file size in Kilobits by the number of seconds in the timeline. For a live broadcast, though, it is impossible to know the average bandwidth of a quality-encoded stream in advance. Tip: By editing an VBR audience file, you can vary the relationships between bit rate and quality. You can also define two additional variations of VBR encoding. For details refer to RealProducer Command Line and Job File Reference. Maximum Video Buffering (Preroll) A video s preroll sets the number of seconds of stream data that the media player must receive before it starts to play the stream. You can modify the preroll by changing the Max Video Buffer setting. use: Sets the number of seconds the video buffers before starting. restrictions: None. 81

90 RealProducer User s Guide Tip: This startup latency does not affect how quickly a downloaded clip begins to play. Increasing the preroll, however, can improve the visual quality in download clips that begin with fast-action sequences. Maximum Key Frame Interval Using the Max Key Frame Interval setting, you can change the video codec s value for the maximum time between key frames. The default value is at least one key frame every 5 seconds. What is a Key Frame? use: Sets the maximum time in seconds between each key frame. restrictions: Poor quality if set too low (1 to 2 seconds, for example). Tip: Under most circumstances, you should not change the default value. If you decide to modify the key frame rate, test the output in a streaming environment to determine if the change produces the desired results. Compressed video encodes full frame data only for certain frames, called key frames. A frame following a key frame encodes information that describes how that frame varies from the preceding frame. The beginning of a new scene typically requires a key frame. A fast-action video typically requires more key frames than a slowly changing video. Advantages of Lowering the Maximum Key Frame Interval Lowering the maximum key frame interval can provide certain benefits: Reduces distortion when streaming in a lossy environment. Distortion results when a frame packet is lost. Using more frequent key frames helps to shorten the stretch of video that may be distorted. Improves a media player s ability to seek to specific points in the video timeline. Costs of Lowering the Maximum Key Frame Time Because key frames encode more data than other frames, lowering the maximum time between key frames either increases the clip s file size or lowers 82

91 CHAPTER 8: Advanced Video Options the clip s image quality. You gain more resilience against data loss, but lose overall compression efficiency. Startup Latency Reduction During Broadcasts A large key frame interval can cause a high stream acquisition latency during live broadcasts. This latency is the time required for the media player to render the stream after it begins to receive the broadcast data. If the media player joins the broadcast just after the broadcast server streams a key frame, the player may have to wait up to five seconds until the next key frame is available. If Helix Server version 11 or later broadcasts the stream, however, it reduces startup latency automatically by buffering each new key frame. This allows it to send key frame data immediately to each media player as it acquires a broadcast stream. 83

92 84 RealProducer User s Guide

93 Part III: BROADCASTING PART III This section covers broadcasting, explaining basic issues and showing how to create server destinations.

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95 Chapter 9: BROADCAST FEATURES CHAPTER 9 This chapter introduces you to the types of broadcasts, explains broadcast options, and covers advanced broadcast features. For More Information: When you are ready to set up a broadcast, Chapter 10 explains how to define server destinations. Live Broadcasting In a live broadcast, RealProducer takes live input from a capture card as described in Capture Input on page 29, encodes it in a streaming format, and sends the stream to a broadcast server for replication and distribution to media players. Live Broadcasting Tip: During a broadcast, you can encode the output as a file destination. This saves the broadcast as an archived, ondemand clip. The section Output File Destination on page 55 explains how to do this. Note: RealProducer can deliver a live broadcast only from live input. To broadcast a file, encode the file in the appropriate format using RealProducer. Then stream the file using the Helix Server SLTA utility. For details, refer to Helix Server Administration Guide. 87

96 RealProducer User s Guide Broadcast Trial Runs When you broadcast live content, you don t get a second chance. It s good practice to perform a trial run to ensure that the broadcast results are acceptable. During the trial run, do the following: Request the stream from the broadcast server. When the media player connects, check that the stream begins to play within a reasonable time. Confirm that the stream rendered by the media player provides an acceptable frame rate and visual quality. Monitor RealProducer to check if it is using too much CPU. Automatic Frame Rate Reduction If RealProducer must reduce the processor load, it reduces the encoded frame rate for the broadcast stream. If this happens, you can do one or more of the following: Move RealProducer to a faster machine. If encoding multiple outputs, reduce the number of outputs. (See Outputs List on page 49.) If encoding multi-rate outputs, reduce the number of audiences encoded for each output. (See Encoding Settings on page 50.) Use an older video codec, such as RealVideo 8 instead of RealVideo 10. (See Video Codec on page 70.) Lower the streaming bit rate for one or more audiences. (See Video Average Bit Rate on page 70.) Reduce the video frame size. (See Frame Size on page 72.) Types of Broadcasts RealProducer provides several broadcast methods. Each method requires that you define a different type of server destination: Push Broadcasting RealProducer delivers the broadcast stream to the designated server as soon as encoding begins. The following broadcasting modes are available: Helix Push Broadcast Helix Advanced Push Broadcast 88

97 CHAPTER 9: Broadcast Features Helix Push Broadcast Helix Multicast Push Broadcast Pull Broadcasting After encoding starts, RealProducer waits for each broadcast server to request the stream. One broadcast method is available: Helix Pull Broadcast A Helix Push broadcast requires little configuration on Helix Server. It provides reliable delivery of the broadcast stream to one or more destinations. server setup: Requires only a user name and password defined within the Helix Server authentication database. bandwidth: Each server destination receives a separate data stream. Each server maintains a separate accounting connection. feedback: Feedback statistics are sent in the accounting connection and displayed in the Monitoring tab. reconnection: Dropped streams are automatically re-established using the accounting connection. For More Information: The section Helix Push Destination on page 105 explains how you set up this type of broadcast in RealProducer. Helix Push Broadcast Connection Steps The following figure illustrates the interaction between RealProducer, Helix Server, and a media player in a Helix Push broadcast. Helix Push Broadcast Sequence of actions in a Helix Push broadcast: 1. RealProducer establishes its monitoring connection with Helix Server. Using this connection, RealProducer sends a user name and password that authenticates its access attempt. 89

98 RealProducer User s Guide 2. After Helix Server authenticates the broadcast, it informs RealProducer how to make the broadcast connection, telling it which server ports to use, for example. 3. RealProducer establishes the broadcast stream connection to Helix Server. It begins to send the encoded packets whether or not any media players have requested the broadcast yet. 4. A viewer typically requests the broadcast by clicking a link in a Web page. This launches the viewer s media player, which requests a broadcast stream from Helix Server. 5. Helix Server streams the broadcast data to the media player. URL for a Helix Push Broadcast For a Helix Push broadcast that the viewer accesses by clicking a link in a Web page, the URL looks like the following: The /ramgen/ mount point launches the media player when the viewer clicks the link in a Web page. The /broadcast/ mount point is the default broadcast mount point. If redundant encoders are used, the mount point is /redundant/. For More Information: See Encoder Redundancy on page 97. A virtual path such as news/ is optional. It is included in the URL only if RealProducer specifies this path along with the stream name. For More Information: See Virtual Paths on page 106. Note: Confer with the Helix Server administrator about the actual URL to use. URLs can vary from the standard format for many reasons. 90

99 CHAPTER 9: Broadcast Features Helix Advanced Push Broadcast Helix Advanced Push is similar to Helix Push broadcasting, but is more efficient with bandwidth, making it a better choice when broadcasting to multiple servers. server setup: Requires that each Helix Server be configured as a broadcast receiver. bandwidth: Each server destination receives a separate data stream. There are no accounting channels. feedback: No feedback from the broadcast server. reconnection: A server can re-establish a lost connection through metadata that is encoded into the data stream periodically. For More Information: The section Helix Advanced Push Destination on page 110 explains how to set up this type of broadcast in RealProducer. Helix Advanced Push Broadcast Steps The following figure shows the interaction between RealProducer, Helix Server, and a media player in a Helix Advanced Push broadcast. Helix Advanced Push Broadcast Sequence of actions in a Helix Advanced Push broadcast: 1. As soon as it starts encoding the broadcast stream, RealProducer sends the stream packets to Helix Server. The password required by the Helix Server receiver is encoded into the data stream. 2. A viewer typically requests the broadcast by clicking a link in a Web page. This launches the viewer s media player, which requests a broadcast stream from Helix Server. 3. Helix Server delivers the broadcast data to the media player. 91

100 RealProducer User s Guide URL for a Helix Advanced Push Broadcast For a Helix Advanced Push broadcast that the viewer accesses by clicking a link in a Web page, the URL looks like the following: The /ramgen/ mount point launches the media player when the viewer clicks the link in a Web page. The /broadcast/ mount point is the default broadcast mount point. If redundant encoders are used, the mount point is /redundant/. For More Information: See Encoder Redundancy on page 97. A virtual path such as news/ is optional. It is included in the URL only if RealProducer specifies this path along with the stream name. Helix Multicast Push Broadcast For More Information: See Virtual Paths on page 111. Note: Confer with the Helix Server administrator about the actual URL to use. URLs can vary from the standard format for many reasons. Helix Multicast Push is similar to Helix Advanced Push, except that the transport is UDP multicast. This type of broadcast allows you to deliver a single stream to multiple, multicast-enabled Helix Servers. server setup: Requires that RealProducer, Helix Servers, and network equipment such as routers be multicast-enabled. bandwidth: Each server destination receives the same multicast stream. There are no accounting channels between servers and RealProducer. feedback: No feedback from the broadcast servers. reconnection: A server can re-establish a lost connection through metadata that is encoded into the data stream periodically. For More Information: The section Helix Multicast Push Destination on page 114 explains how to set up this type of broadcast. 92

101 CHAPTER 9: Broadcast Features Helix Multicast Push Illustration The following figure illustrates multicasting. Because each server receives the same stream, multicasting allows you to broadcast to any number of server destinations without increasing the outgoing bandwidth from RealProducer. Helix Multicast Push Note: Multicasting may not be possible if RealProducer or any of the Helix Servers needs to communicate to another broadcast component across the Internet. Tip: Multicasting can also be used for broadcasting across a one-way satellite network where two-way connections are not possible. URL for a Helix Multicast Push Broadcast For a Helix Multicast Push broadcast that the viewer accesses by clicking a link in a Web page, the URL looks like the following: The /ramgen/ mount point launches the media player when the viewer clicks the link in a Web page. The /broadcast/ mount point is the default broadcast mount point. If redundant encoders are used, the mount point is /redundant/. For More Information: See Encoder Redundancy on page 97. A virtual path such as news/ is optional. It is included in the URL only if RealProducer specifies this path along with the stream name. For More Information: See Virtual Paths on page

102 RealProducer User s Guide Helix Pull Broadcast Note: Confer with the Helix Server administrator about the actual URL to use. URLs can vary from the standard format for many reasons. In pull broadcasting, RealProducer begins to generate broadcast packets as soon as you start the encoding process. However, it does not deliver the broadcast stream until Helix Server requests the stream. server setup: Requires that Helix Server be configured as a pull-enabled receiver. bandwidth: Each server receives a separate stream that it requests when needed and drops when no longer in use. feedback: No feedback statistics sent by the servers. reconnection: Each server can automatically re-establish a stream that it has dropped. For More Information: The section Helix Pull Destination on page 118 explains how to set up a pull broadcast. Helix Pull Broadcast Steps The following figure illustrates the interaction between RealProducer, Helix Server, and a media player in a pull broadcast. Helix Pull Broadcasting Sequence of actions in a Helix Pull broadcast: 1. RealProducer begins encoding the stream, but the output is not immediately sent to Helix Server. 2. The first audience member requests the broadcast, typically by clicking a link in a Web page. This launches the media player, which requests the broadcast stream from Helix Server. 94

103 CHAPTER 9: Broadcast Features 3. Helix Server requests the broadcast stream from RealProducer, sending it information about the server address and ports to use. Once the connection is established, Helix Server sends keep-alive requests as long as viewers are receiving the broadcast. 4. RealProducer sends the broadcast stream to Helix Server, terminating the stream when it receives no more keep-alive messages. 5. Helix Server streams the broadcast to media players. Example of Pull Broadcasting An example of a pull broadcast is an online radio station that continuously encodes input. The stream is delivered to a specific Helix Server only if a listener requests the stream from that server. If all listeners on the server stop the broadcast, Helix Server drops the stream, re-requesting it only if new listeners request the broadcast. Stream Acquisition Latency Because a Helix Pull broadcast does not begin until the first media player requests the broadcast, the first viewer may experience a longer than normal delay as Helix Server contacts RealProducer to acquire the broadcast stream. After the server acquires the stream, however, subsequent viewers experience no additional delay. Outgoing Bandwidth When you use pull splitting, you do not have control over how many Helix Servers pull the stream. Any server that knows the RealProducer address, stream name, and access password can request the stream. You therefore have less control over your outgoing RealProducer bandwidth than you do with push splitting, in which you define exactly which servers receive the stream. Note: Each Helix Server that requests the broadcast receives a separate stream. Multicasting is not available with pull splitting. URL for a Pull Broadcast The URL to a Helix Pull broadcast is longer than a URL to a push broadcast because it includes information about both the Helix Server receiver and the RealProducer transmitter. 95

104 RealProducer User s Guide The following example shows the general format for a basic Helix Pull broadcast that the viewer accesses by clicking a link in a Web page. For convenience, the example is displayed on two lines. The first line gives the receiver information. The second line supplies the transmitter parameters: producer.example.com:3031/news/live.rm The /ramgen/ mount point launches the media player when the viewer clicks the link in a Web page. The /broadcast/ mount point is the default mount point used by Helix Server for a broadcast. Following the broadcast mount point is a path that indicates pull splitting is used, as in /pull/. The Helix Server receiver defines this path. The link s transmitter portion lists the RealProducer IP address or host name, along with its listen port, as in producer.example.com:3031. A virtual path such as news/ is optional. It is included in the URL only if RealProducer specifies this path along with the stream name. For More Information: See Virtual Paths on page 120. Server Broadcast Mode The broadcast method you use with RealProducer affects only the delivery of the broadcast stream to the server. The broadcast server, in turn, determines the method for broadcasting the live stream to media players. For example, RealProducer may deliver the stream to the server in pull mode while the server broadcasts in push mode. Options that you choose for the encoder-to-server broadcast stream do not necessarily affect streams that the server delivers to other servers or to media players. For example, you might choose a 20 percent forward error correction (FEC) rate in a push broadcast. This FEC rate affects only the encoder-toserver stream. A Helix Server transmitter can forward (split) the stream to a Helix Server receiver using a different FEC rate. Streams delivered to media players include no FEC packets. For More Information: Refer to the chapter on transmitters and receivers in Helix Server Administration Guide for information about replicating streams from one server to another. 96

105 CHAPTER 9: Broadcast Features Broadcast Transports When you run a push broadcast other than a multicast, you specify whether to use TCP or UDP for the broadcast stream sent to the server. The server, however, determines whether TCP or UDP is used in the broadcast streams replicated to media players. UDP The UDP transport is preferred because of its lower network overhead. However, UDP connections do not receive notice if broadcast packets are lost. A server can generally notify RealProducer if it requires data to be resent, however. A firewall between RealProducer and the server may block UDP packets. The best solution is to configure the firewall to allow UDP packets through the ports that RealProducer and the server use for the broadcast data stream. TCP The TCP transport establishes a two-way connection between RealProducer and the server. If a broadcast packet is lost, the network itself requests the packet to be resent. This makes TCP a highly reliable method for broadcasting on networks prone to data loss. TCP is also likely to pass through firewalls that you cannot configure to accept UDP communications. TCP incurs a higher network overhead, however. A server generally does not need all broadcast packets to keep the stream flowing. Packets re-requested by the TCP transport may arrive at Helix Server too late to be useful. Hence, using TCP involves network-related overhead that may not benefit the broadcast. Encoder Redundancy When broadcasting in Helix Push or Helix Advanced Push mode, you can provide encoder redundancy by using two or more RealProducers to encode the same live event. When you start each broadcast stream, you specify the same stream name, but add a unique, numbered delimiter, such as.1 or.2. When the RealProducers connect to Helix Server, they form a queue based on connection order. Consider this example: 97

106 RealProducer User s Guide live.rm.2 connects first live.rm.3 connects second live.rm.1 connects third Under normal circumstances all viewers receive the stream live.rm, and have no knowledge of which RealProducer encoded the stream. In the preceding example, live.rm originates as live.rm.2. If the RealProducer delivering live.rm.2 fails, the media players connect to the next live.rm stream in the queue, which is live.rm.3. If live.rm.2 returns, it goes to the bottom of the queue. A subsequent failure of live.rm.3 causes media players to connect to live.rm.1, and so on. RealProducer Redundancy Note: Encoder redundancy changes the broadcast URL. The Helix Server administrator may also require the use of a different delimiter, such as a tilde (~), in the stream identifier. Refer to the unicasting chapter of Helix Server Administration Guide. Tip: To provide optimal redundancy, each encoder should be as independent as possible. For example, use multiple video cameras connected to separate RealProducer computers that use different power supplies and network connections. Forward Error Correction When forward error correction (FEC) is used, RealProducer adds error correction packets to the broadcast stream. If packets containing broadcast data are lost, Helix Server can often reconstruct the data using the error 98

107 CHAPTER 9: Broadcast Features correction information. You can include forward error correction with broadcasts that use the UDP transport. The setting is ignored for any broadcast that uses TCP. Error Correction Percentage Tip: Forward error correction is most useful when sending a broadcast stream over a lossy network such as the Internet. If your RealProducer and Helix Server are on the same local area network, you may not need to use any error correction. The greater the FEC percentage, the higher the packet loss protection and the greater the bandwidth needed for the stream. A standard value of 20 percent means that one in five packets is for error correction. The stream also uses 20 percent more bandwidth than if error correction was turned off. Redundant Stream Protection Note: Using FEC increases the bandwidth only for the stream between RealProducer and Helix Server. It does not affect the bandwidth of the broadcast streams delivered to media players by Helix Server. You can turn the FEC percentage up to 100%, effectively creating a redundant stream that provides maximum protection against packet loss. This doubles the outgoing bandwidth between RealProducer and Helix Server, however. When you use full stream redundancy, you can set an offset in seconds between each packet and its redundant packet. This reduces the chance that both packets will be lost. For example, an offset value of 2 means that after it transmits a certain packet to Helix Server, RealProducer waits two seconds before transmitting the redundant packet. FEC Rates and Receiver Buffering Note: Packet redundancy does not protect against the failure of the encoding process. Use encoder redundancy to protect against RealProducer going offline during a broadcast. See Encoder Redundancy on page 97. When you use FEC, the Helix Server administrator may need to increase the buffering of the broadcast stream. If an FEC packet arrives after the server 99

108 RealProducer User s Guide broadcasts the portion of the stream that the FEC packet corrects, the packet is useless. Full Stream Redundancy Buffering Levels If you use full stream redundancy, Helix Server must buffer the stream at least as long as the redundant packet offset value. For example, if RealProducer transmits redundant stream packets five seconds after the initial stream packets, the Helix Server receiver needs to buffer the stream for a minimum of five seconds. Partial Stream Redundancy Buffering Levels When you use partial stream redundancy, broadcasting low-bandwidth video streams with an error correction rate lower than 20 percent may require raising the receiver buffering time. For More Information: The chapter on transmitters and receivers in Helix Server Administration Guide explains how to set the receiver buffering based on the transmitter FEC rate. Archiving When you broadcast a live event, you can write the stream to a clip for archiving or for streaming on-demand. You can archive a RealMedia clip through RealProducer, Helix Server, or both. A primary consideration is disk space. Writing a long broadcast to a clip can consume considerable disk space depending on the broadcast bandwidth. RealProducer Archiving Tip: The server may have more available space than your RealProducer computer. As well, creating the archive on the server eliminates the need to upload the archive clip later if you want to stream it on demand. To archive a broadcast on RealProducer, you define a clip destination along with the server destination. RealProducer automatically creates a new clip if the existing archive reaches the operating system limit (typically 2 or 4 Gigabytes). 100

109 CHAPTER 9: Broadcast Features Tip: If you run a RealMedia broadcast from the command line or manually create a job file for the broadcast, you can specify a different file-rolling limit based on broadcast time or file size. For More Information: The section Output File Destination on page 55 explains how to create an archive clip. Helix Server Archiving The Helix Server administrator can turn on archiving for RealMedia broadcasts. Like RealProducer, Helix Server can create multiple archive files based on the broadcast time (such as a new file every 15 minutes), or file size (20 Megabytes per file, for example). The administrator can also set up selective archiving rules that archive only certain broadcast streams based on the presence of a virtual path in the stream name. For More Information: See the unicasting chapter of Helix Server Administration Guide for information about archiving. Version 6 IP Addresses RealProducer supports DNS names, version 4 IP addresses (IPv4), and version 6 IP addresses (IPv6) for delivering a broadcast stream to a server. Note the following about using IPv6 addresses: RealProducer supports full IPv6 syntax, such as the following: 1080:0:0:0:8:800:200C:417A It also supports the use of a double colon ( :: ) to compress leading or trailing fields containing only zeroes, as in the following: 1080::8:800:200C:417A RealProducer will not broadcast to a reserved multicast address. However, it will multicast to permanent or nonpermanent addresses, which always begin with FF, as in FF15:0:0:0:0:0:0:101. Tip: Whenever possible, use a domain name instead of an IPv6 address. 101

110 102 RealProducer User s Guide

111 Chapter 10: SERVER DESTINATIONS CHAPTER 10 Server destinations deliver a live stream to a server. The server then broadcasts the stream to media players. The procedure for delivering a live stream depends on the type of broadcast server that RealProducer uses. Note: You must create an output as explained in Chapter 5 before you can assign a server destination to an output. For More Information: Refer to Chapter 9 for background about broadcasting options. Server Destinations You create a server destination for a selected output in the Output Servers section of the Output tab. Each server destination defines a set of broadcast parameters, such as the server IP address and password. Output Servers Settings Output Servers Buttons The buttons in the Output Servers section allow you to configure the server destinations: Add a destination server template to the selected output. Edit the broadcast settings for the selected server template. 103

112 RealProducer User s Guide Save the settings to a new server template. Delete the selected server destination from the output. (This does not delete the template.) Server Destination Templates Click the Add button to add a server destination to the output highlighted in the Outputs List. The pop-up dialog displays the server templates stored in the RealProducer servers subdirectory. Add Server Destinations In the Templates of Server Type drop-down, choose one of the following based on the type of broadcast you want to run: All Helix Broadcast Types All broadcast types for Helix Server. Helix Push See Helix Push Destination on page 105. Helix Advanced Push See Helix Advanced Push Destination on page 110. Helix Multicast Push See Helix Multicast Push Destination on page 114. Helix Pull See Helix Pull Destination on page 118. If you have defined a customized server destination template that you want to use, click the template name. Otherwise, select the Default template. Then click Add to Job. 104

113 CHAPTER 10: Server Destinations Tip: Using the preferences, you can select a server destination that is used automatically whenever you create an output. See Output Preferences on page 138. Template Filtering by Name You can filter the templates shown in the server destinations pop-up by typing a string in the Where name matches field. Only destination names that contain the string then display. Text matching is not case-sensitive. Multiple Server Destinations You can deliver each broadcast stream to one or more broadcast servers. In the server destinations pop-up, use Ctrl+click to select multiple, discrete server destinations. Use Shift+click to select a range of destinations. You can also add destinations one at a time by clicking the Add button repeatedly. Note: Each push server destination you add increases the outgoing bandwidth requirements, unless you use multicasting. Server Template Creation After you set up your server destinations, you can save modifications for future jobs. Once you finish customizing a server destination, highlight the server destination name and click the Save As button. A standard save dialog allows you to choose a new template name. Or you can select an existing template to overwrite that template. Templates are saved in servers subdirectory of the RealProducer installation directory using the file extension.rpsd. Tip: Use a descriptive name that clearly identifies the purpose of the template. Helix Push Destination A Helix Push broadcast is a simple method for delivering a live stream to Helix Server. RealProducer delivers the broadcast stream to the destination Helix Server as soon as encoding begins. Note: If you are not familiar with this broadcast method, refer to the section Helix Push Broadcast on page 89 for background information. 105

114 RealProducer User s Guide Helix Push Basic Settings A Helix Push destination defines the stream name and Helix Server address, along with a name and password that provides access to the server. Basic Settings for the Helix Push Server Destination Name Enter a description for this server destination in the Name field. For example, the name might identify the broadcast method and indicate the Helix Server that receives the stream. This name is for your reference only. It does not affect the broadcast. Server Type In the Server Type drop-down, select Helix Push. Stream Name In the Stream Name field, enter a name for the broadcast stream. This name should use the appropriate extension for the output type. It appears in links to the broadcast URL. Note: The stream name can include uppercase or lowercase letters, numbers, an underscore (_), and a hyphen (-). Spaces are not allowed. Virtual Paths If you want to archive or split the broadcast on Helix Server, the server administrator first sets up a virtual path such as news/ that defines archiving or splitting rules. You then precede the stream name with this path, as in news/live.rm, to utilize the rule. 106

115 CHAPTER 10: Server Destinations For More Information: See the chapter on transmitters and receivers in Helix Server Administration Guide for details about using virtual paths. Encoder Redundancy If you are using encoder redundancy, include the appropriate stream delimiter and a unique number for this encoder. For example: live.rm.2 For More Information: See Encoder Redundancy on page 97. Server Address For Server Address, enter the version 4 IP address, version 6 IP address, or DNS name of the Helix Server that receives the broadcast stream. The following are examples of each type of address: FEDC:BA98:7654:3210:FEDC:BA98:7654:3210 helixserver.example.com. Server HTTP Port For Server HTTP Port, specify the HTTP port value on Helix Server. The default value is port 80, which is the default HTTP port on Helix Server. RealProducer uses this port to contact Helix Server once encoding has begun. Data Ports When RealProducer contacts Helix Server on its HTTP port, the two negotiate which ports to use for the broadcast data. The broadcast requires at least two data ports on Helix Server whether the transport is TCP or UDP. Possible ports are in the range to unless the Helix Server administrator changes the default range. Username and Password In the Username and Password fields, enter a valid encoder user name and password. These values are defined in the Helix Server authentication database under the SecureRBSEncoder realm. The broadcast connection fails if either value is incorrect. For More Information: For details, refer to the unicasting and authentication chapters of Helix Server Administration Guide. 107

116 RealProducer User s Guide Save Password in Job Click Save Password in Job to store the password in the current job file. Warning! The password is saved as plain text in the server template and any job file that later uses this server destination. Be sure to maintain appropriate security on these files. Transport Under Transport, click the radio button for UDP or TCP to select the transport to use for the broadcast stream. Helix Push Advanced Settings Note: The monitoring connection of a Helix Push broadcast always uses TCP whether the data transport stream is UDP or TCP. For More Information: See Broadcast Transports on page 97. Click the Advanced Settings button to display additional options for the Helix Push server destination. You should not modify the advanced settings values unless you have a specific reason to do so. Advanced Settings for the Helix Push Server Destination Reconnect Interval The Reconnect Interval value defines the number of seconds that RealProducer waits before attempting to reconnect to Helix Server. The interval period begins once the operating system terminates the TCP accounting connection because it has received no response from Helix Server. The default value is

117 CHAPTER 10: Server Destinations Statistics Update Interval The statistics update interval determines how frequently Helix Server sends statistics reports to RealProducer during a Helix Push broadcast. The default value is 30 seconds. Listen Address RealProducer uses the IP address or domain name listed in the Listen Address field to listen for resend requests from Helix Server. Use the drop-down to select the version 4 or version 6 IP address that you want to use on the RealProducer machine. You can also enter a domain name or IP address manually. Tip: Using an IP address of the RealProducer machine may not work when you broadcast through a network address translation (NAT) firewall. In this case, set the listen address to instead. Accept Resend Requests If Helix Server loses broadcast packets and cannot reconstruct them using forward error correction, it can request that RealProducer resend the packets from its stream buffer. To enable RealProducer to respond to these requests, check the Accept Resend Requests from Server box. Tip: It s generally OK to accept resend requests. However, because these requests increase network overhead slightly, you may want to turn the resend feature off to keep tight control over bandwidth. Forward Error Correction The Percent Error Correction field sets the percentage of stream bandwidth dedicated to forward error correction packets if the transport is UDP. A value of 20, for example, increases outgoing bandwidth 20 percent by making every fifth packet an FEC packet. If you set the error correction percentage in the range of 51 to 100, you set up a redundant stream. In this case, the Redundant Packets Offset field defines how many seconds separate an original packet from its redundant packet. For More Information: The section Forward Error Correction on page 98 provides background about FEC features. 109

118 RealProducer User s Guide Helix Advanced Push Destination In a Helix Advanced Push broadcast, RealProducer acts as a transmitter for delivering a live stream. The Helix Server that receives the broadcast stream is set up as a receiver. This robust broadcast method requires coordinated setup on both ends. Helix Advanced Push Basic Settings Note: If you are not familiar with this broadcast method, refer to the section Helix Advanced Push Broadcast on page 91 for background information. For More Information: The chapter on transmitters and receivers in Helix Server Administration Guide explains how to set up Helix Server as a receiver. A Helix Advanced Push destination sets the stream name and provides the information necessary to connect to the Helix Server receiver. Basic Settings for the Helix Advanced Push Server Destination Name Enter a description for this server destination in the Name field. For example, the name might identify the broadcast method and indicate the intended receiver. This name is for your reference only. It does not affect the broadcast. Server Type In the Server Type drop-down, select Helix Advanced Push. 110

119 CHAPTER 10: Server Destinations Stream Name In the Stream Name field, enter a name for the broadcast stream. This name should use the appropriate extension for the output type. It appears in links to the broadcast URL. Note: The stream name can include uppercase or lowercase letters, numbers, an underscore (_), and a hyphen (-). Spaces are not allowed. Virtual Paths If you want to archive or split the broadcast on Helix Server, the server administrator first sets up a virtual path such as news/ that defines archiving or splitting rules. You then precede the stream name with this path, as in news/live.rm, to utilize the rule. For More Information: See the chapter on transmitters and receivers in Helix Server Administration Guide for details about using virtual paths. Encoder Redundancy If you are using encoder redundancy, include the appropriate stream delimiter and a unique number for this encoder. For example: live.rm.2 For More Information: See Encoder Redundancy on page 97. Server Address For Server Address, enter the version 4 IP address, version 6 IP address, or DNS name of the Helix Server receiver used for the broadcast. The following are examples of each type of address: FEDC:BA98:7654:3210:FEDC:BA98:7654:3210 helixserver.example.com. Note: The Helix Server receiver definition must specify the RealProducer IP address as its transmitter source. See the chapter on transmitters and receivers in Helix Server Administration Guide. 111

120 RealProducer User s Guide Server Port For Server Port, specify a Helix Server port used by the receiver for incoming data. Receiver ports are typically to 30020, but the Helix Server administrator may change this range. The default server port that RealProducer uses for data transmission is Password In the Password field, enter a valid receiver password. This password is stored as part of the Helix Server receiver configuration. Note the following: The password does not need to be defined in the Helix Server authentication database. A user name is not needed with this type of broadcast. Optionally, the receiver can require no authentication. In this case, leave Password blank. Warning! Non-authenticated transmission should be used only if RealProducer and Helix Server are on the same local network and a firewall blocks attempts by outside encoders to reach Helix Server. Save Password in Job Click Save Password in Job to store the password in the current job file. Warning! The password is saved as plain text in the server template and any job file that later uses this server destination. Be sure to maintain appropriate security on these files. Transport Under Transport, click the radio button for UDP or TCP to select the transport to use for the broadcast stream. Note: The Helix Server receiver configuration must specify the same transport. See the chapter on transmitters and receivers in Helix Server Administration Guide. For More Information: See Broadcast Transports on page

121 CHAPTER 10: Server Destinations Helix Advanced Push Advanced Settings Click the Advanced Settings button to display additional options for the Helix Advanced Push server destination. You should not modify the advanced settings values unless you have a specific reason to do so. Advanced Settings for the Helix Advanced Push Server Destination Reconnect Interval The Reconnect Interval setting defines the interval in seconds at which RealProducer encodes metadata values into the broadcast stream. These values allow Helix Server to reconnect to a dropped broadcast stream. The default is 30 seconds. Listen Address RealProducer uses the IP address or domain name listed in the Listen Address field to listen for resend requests from Helix Server. Use the drop-down to select the version 4 or version 6 IP address that you want to use on the RealProducer machine. You can also enter a domain name or IP address manually. Tip: Using an IP address of the RealProducer machine may not work when you broadcast through a network address translation (NAT) firewall. In this case, set the listen address to instead. Accept Resend Requests If Helix Server loses broadcast packets and cannot reconstruct them using forward error correction, it can request RealProducer to resend the packets from its stream buffer. To enable RealProducer to respond to these requests, check the Accept Resend Requests from Server box. 113

122 RealProducer User s Guide Tip: It s generally OK to accept resend requests. However, because these requests increase network overhead slightly, you may want to turn the resend feature off to keep tight control over bandwidth. Note: The Helix Server receiver configuration can turn off the feature for making resend requests. In this case, the RealProducer setting has no effect because the server will never make these requests. Forward Error Correction The Percent Error Correction field sets the percentage of stream bandwidth dedicated to forward error correction packets if the transport is UDP. A value of 20, for example, increases outgoing bandwidth 20 percent by making every fifth packet an FEC packet. If you set the error correction percentage in the range of 51 to 100, you set up a redundant stream. In this case, the Redundant Packets Offset field defines how many seconds separate an original packet from its redundant packet. For More Information: The section Forward Error Correction on page 98 provides background about FEC features. Helix Multicast Push Destination In a multicast, RealProducer acts as a transmitter that delivers a live stream. Multiple, multicast-enabled Helix Servers function as receivers. This configuration requires a multicast-enabled network as well as coordinated setup on both ends. Note: If you are not familiar with this broadcast method, refer to the section Helix Multicast Push Broadcast on page 92 for background information. For More Information: The chapter on transmitters and receivers in Helix Server Administration Guide explains how to set up each Helix Server receiver. 114

123 CHAPTER 10: Server Destinations Helix Multicast Push Basic Settings The following figure illustrates the basic settings for a Helix Multicast Push destination. Basic Settings for the Helix Multicast Push Server Destination Tip: Unlike Helix Push and Helix Advanced Push broadcasts, which require a separate server destination for each broadcast server, a Helix Multicast Push broadcast requires just one server destination. Any number of multicast-enabled servers can then receive the stream by listening to the defined multicast address and port. Name Enter a description for this server destination in the Name field. For example, the name might identify the broadcast as a multicast to a known set of receivers. This name is for your reference only. It does not affect the broadcast. Server Type In the Server Type drop-down, select Helix Multicast Push. Stream Name In the Stream Name field, enter a name for the broadcast stream. This name should use the appropriate extension for the output type. It appears in links to the broadcast URL. Note: The stream name can include uppercase or lowercase letters, numbers, an underscore (_), and a hyphen (-). Spaces are not allowed. 115

124 RealProducer User s Guide Virtual Paths If you want to archive or split the broadcast on Helix Server, the server administrator first sets up a virtual path such as news/ that defines archiving or splitting rules. You then precede the stream name with this path, as in news/live.rm, to utilize the rule. For More Information: See the chapter on transmitters and receivers in Helix Server Administration Guide for details about using virtual paths. Multicast Address For Multicast Address, enter a version IP version 4 or 6 multicast address: Multicast Port IPv4 multicast addresses are in the range to IPv6 multicast addresses have the prefix ff00::/8. Note: The Helix Server receiver definition must specify the RealProducer IP address as its transmitter source. It must also define udp/multicast as the transport. See the chapter on transmitters and receivers in Helix Server Administration Guide. For Multicast Port, specify a Helix Server port used by the receiver for incoming data. Receiver ports are typically to 30020, but the Helix Server administrator may change this range. The default Helix Server port that RealProducer uses for data transmission is Note: Ensure that any firewalls between RealProducer and the Helix Servers allow UDP data sent to Helix Server on the chosen ports. Password In the Password field, enter a valid receiver password. This password is stored as part of the Helix Server receiver configuration. Note the following: The password does not need to be defined in the Helix Server authentication database. A user name is not needed with this type of broadcast. Optionally, the receiver can require no authentication. In this case, leave Password blank. 116

125 CHAPTER 10: Server Destinations Warning! Non-authenticated transmission should be used only if RealProducer and all Helix Servers are on the same local network and a firewall blocks attempts by outside encoders to reach any of the Helix Servers. Save Password in Job Click Save Password in Job to store the password in the current job file. Transport Warning! The password is saved as plain text in the server template and any job file that later uses this server destination. Be sure to maintain appropriate security on these files. For a multicast, the Transport field is not selectable because multicasts always use the udp/multicast transport. Helix Multicast Push Advanced Settings Click the Advanced Settings button to display additional options for the Helix Multicast Push server destination. You should not modify the advanced settings values unless you have a specific reason to do so. Advanced Settings for the Helix Multicast Push Server Destination Multicast TTL For Multicast TTL, specify a packet time-to-live of 0 to 255. As a multicast data packet passes through a multicast-enabled router, its time-to-live decreases by 1. When the value reaches 0, the router discards the data packet. The larger the 117

126 RealProducer User s Guide value, the greater the distance each packet can travel. The following table summarizes possible values. Time to Live (TTL) Values TTL Value Packet Range 0 local host 1 local network (subnet) 16 intranet 32 site 64 region 128 continent 255 world Tip: The default value of 16 typically keeps multicast packets within an internal network. Reconnect Interval The Reconnect Interval setting defines the interval in seconds at which RealProducer encodes metadata values into the broadcast stream. These values allow Helix Servers to reconnect to a dropped broadcast stream. The default is 30 seconds. Forward Error Correction The Percent Error Correction field sets the percentage of stream bandwidth dedicated to forward error correction packets. A value of 20, for example, increases outgoing bandwidth 20 percent by making every fifth packet an FEC packet. If you set the error correction percentage in the range of 51 to 100, you set up a redundant stream. In this case, the Redundant Packets Offset field defines how many seconds separate an original packet from its redundant packet. For More Information: The section Forward Error Correction on page 98 provides background about FEC features. Helix Pull Destination In pull broadcasting, RealProducer begins to generate broadcast packets as soon as you start the encoding process. However, it does not deliver the 118

127 CHAPTER 10: Server Destinations broadcast stream until a Helix Server requests the stream. In a Helix Pull broadcast, RealProducer acts as a transmitter and Helix Server functions as a pull-enabled receiver. Helix Pull Basic Settings Note: If you are not familiar with this broadcast method, refer to the section Helix Pull Broadcast on page 94 for background information. For More Information: The chapter on transmitters and receivers in Helix Server Administration Guide explains how to set up the server as a pull-enabled receiver. The following figure illustrates the basic settings for a Helix Pull destination. Basic Settings for the Helix Pull Server Destination Tip: Unlike Helix Push and Helix Advanced Push broadcasts, which require a separate server destination for each broadcast server, a Helix Pull broadcast requires just one server destination. Any number of servers can then pull the stream by contacting RealProducer on its listen port. Name Enter a description for this server destination in the Name field. With an online radio station, for example, the name might identify the type of music being broadcast. This name is for your reference only. It does not affect the broadcast. 119

128 RealProducer User s Guide Server Type In the Server Type drop-down, select Helix Pull. Stream Name In the Stream Name field, enter a name for the broadcast stream. This name should use the appropriate extension for the output type. It appears in links to the broadcast URL. Note: The stream name can include uppercase or lowercase letters, numbers, an underscore (_), and a hyphen (-). Spaces are not allowed. Virtual Paths If you want to archive or split the broadcast on Helix Server, the server administrator first sets up a virtual path such as news/ that defines archiving or splitting rules. You then precede the stream name with this path, as in news/live.rm, to utilize the rule. For More Information: See the chapter on transmitters and receivers in Helix Server Administration Guide for details about using virtual paths. Encoder Address For Encoder Address, select the version 4 or version 6 IP address used by RealProducer to listen for pull requests. If your computer has just one IP address, that address is selected by default in the drop-down list.the following are examples of each type of address: FEDC:BA98:7654:3210:FEDC:BA98:7654:3210 helixserver.example.com. Note: The Helix Server receiver definition must specify the RealProducer IP address as its transmitter source. See the chapter on transmitters and receivers in Helix Server Administration Guide. Encoder Listen Port For Encoder Listen Port, specify the RealProducer port used to listen for stream pull requests. You can use any available port up to The default is

129 CHAPTER 10: Server Destinations Note: The Helix Server receiver must be configured to contact RealProducer on this port. See the chapter on transmitters and receivers in Helix Server Administration Guide. Data Ports RealProducer does not transmit broadcast data on the listen port. Rather, both RealProducer and Helix Server define a range of ports for stream data. They negotiate which ports to use during the initial pull request. The default ports on both are to Tip: Ensure that any firewalls between RealProducer and Helix Server allow UDP data sent to Helix Server on the ports in the defined range. Password In the Password field, enter a valid receiver password. This password is stored as part of the Helix Server receiver configuration. Note the following: The password does not need to be defined in the Helix Server authentication database. A user name is not needed with this type of broadcast. Optionally, the receiver can require no authentication. In this case, leave Password blank. Save Password in Job Warning! Non-authenticated transmission should be used only if RealProducer and Helix Server are on the same local network and a firewall blocks attempts by outside encoders to reach Helix Server. For More Information: For receiver configuration details, refer to the chapter on transmitters and receivers in Helix Server Administration Guide. Click Save Password in Job to store the password in the current job file. Warning! The password is saved as plain text in the server template and any job file that later uses this server destination. Be sure to maintain appropriate security on these files. 121

130 RealProducer User s Guide Transport For a pull broadcast, the Transport field is not selectable because pull broadcasts use the transport defined by the Helix Server receiver. Helix Pull Advanced Settings Click the Advanced Settings button to display additional options for the Helix Pull server destination. You should not modify the advanced settings values unless you have a specific reason to do so. Advanced Settings for the Helix Pull Server Destination Note: In a Helix Pull broadcast, the Helix Server receiver configuration sets up most of the advanced broadcast features, such as forward error correction parameters. Keep Alive Timeout The Keep Alive Timeout value specifies the number of seconds that RealProducer waits before it stops transmitting broadcast packets after it receives no more keep-alive messages from Helix Server. This conserves bandwidth by dropping a stream no longer in use. The Helix Server that drops the stream can re-establish it if necessary, however. The default timeout value is 30 seconds. Tip: You can raise the value if previous pull broadcasts have timed out while viewers were still receiving the broadcast. RealNetworks does not recommend that you lower the value. Note: A keep-alive timeout stops only the transmission of the packets. It does not stop the encoding of the packets. You must stop the encoder manually. 122

131 Part IV: MONITORING PART IV This section explains how to monitor an encoding session to check for errors and view encoding statistics.

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133 Chapter 11: JOB MONITORING CHAPTER 11 This chapter explains how to start an encoding job and describes how to monitor a job in progress. Monitoring Tab Click the Monitoring tab to display the controls that help you to monitor encoding jobs. Monitoring Tab The controls on the Monitoring tab allow you to do the following: Start and stop an encoding job (see Starting a Job on page 126). Preview video output (see Preview Section on page 126). Monitor audio levels (see Audio Meters on page 127). 125

134 RealProducer User s Guide View session errors (see Session Logging on page 129). Note: The settings advisor may also display above the Monitoring tab if RealProducer detects problems with the encoding settings. The section Settings Advisor on page 130 explains this feature. Starting a Job Once you have set up the inputs and outputs for a job and there are no critical error messages noted by the settings advisor, you can start the encoding process. Do this by selecting Control>Start Job, pressing Ctrl+j, or clicking the Start Job button on the toolbar. When you encode a clip or set a duration on captured input (see Input Duration on page 29), encoding stops automatically when the job is complete. To stop the encoding process manually, select Control>Stop Job or click the Stop Job button on the toolbar. Note: If there are multiple outputs or destinations, stopping the job halts the encoding process for all outputs and destinations. You cannot stop the encoding for one output or for one destination (such as a clip) while continuing it for another destination (such as a broadcast server). Preview Section The top section of the Monitoring tab contains two preview monitors. When the encoding job includes video, the input source video plays in the left-hand monitor, which shows the effects of all prefilters that have been applied. The encoded output displays in the right-hand monitor. 126

135 CHAPTER 11: Job Monitoring Input and Output Preview Monitors The control in the upper-left corner of the Preview section allows you to show or hide the monitors. Monitors Hidden Click to expand the Preview section. Monitors Displayed Click to hide the section. Multiple Output Display Tip: Hiding the monitors can speed the encoding process by eliminating the need for RealProducer to display the video onscreen. This is useful during live broadcasts in which you want to conserve as much processing power as possible. When you encode multiple outputs, use the Output drop-down to select which output to monitor in the right-hand monitor window. If the output encodes more than one audience, select the audience by encoding speed using the Bitrate drop-down. Audio Meters As you encode the output, you can monitor the audio levels for both the input audio and the encoded output audio. 127

136 RealProducer User s Guide Audio Meter Clipped Audio By monitoring the audio meters, you can ensure that the audio levels are in the optimal dynamic range: green Normal dynamic range. red Audio is close to being overmodulated. For More Information: The section Audio Level on page 38 explains how to use the audio gain prefilter to boost or cut the input s audio level. If audio registers above the possible dynamic range, the clipping indicator above the audio meter lights up. To eliminate the distortion, you may need to modify the setting of the audio level prefilter or adjust the settings in your audio mixing hardware or software. For example, the sound capture card may have its mixer levels set too high. In this case, adjust the analog gains leading to your sound card input so that the input audio meter on RealProducer never rises to the 0 db level. If needed, modify audio gain through an external mixer board if the sound card s audio mixer does not provide adequate control. Tip: External mixing may lead to sound levels that are too low on average. In this case, you can use the audio level prefilter to bring the signal back up to acceptable levels. This is safe to do because the prefilter will not introduce clipping. 128

137 CHAPTER 11: Job Monitoring Session Logging RealProducer records messages about encoding tasks as they occur. This informs you about RealProducer performance, such as its CPU use. After a job has run, you can view the producer.log log file in the main installation directory to find encoding errors messages. You can also use the session log viewer to monitor encoding information as the job runs. Session Log Viewer For More Information: The preferences file (producer.pref) sets the log file location and features. It also determines which types of messages display in the log viewer. For details, refer to Log File Preferences on page 135. The session log viewer appears at the bottom of the Monitoring tab. It provides a real-time view of log messages as RealProducer generates them. The control in the upper-left corner of the Session Logging section allows you to show or hide the previews. Session Logging Hidden Click to display Session Logging. Session Logging Displayed Click to hide the section. Logging Types Tip: Click Clear Log to remove existing messages from the screen. This does not delete the messages from the log file, however. Note: Watching the log viewer is useful when you encode a live broadcast. The messages can alert you to problems such as excess CPU consumption and lowered frame rates. You can organize the log messages by type by clicking the Type column header. All messages are one of the following types: error warning Error messages indicate significant problems that have occurred in the encoding process. They typically cause the job to fail. Warning messages indicate serious issues that occurred but did not cause the encoding job to fail. 129

138 RealProducer User s Guide informational diagnostic Informational messages provide important information about the encoding operation. Diagnostic messages convey non-critical messages about the encoding operation. Tip: The preferences file (producer.pref) determines which message types are logged. By default, diagnostic messages are not recorded. See Log File Preferences on page 135. For More Information: For information about changing the logging settings, refer to Log File Preferences on page 135. Settings Advisor RealProducer displays the settings advisor at the top of the Monitor, Input, and Output tabs to inform you that it has detected problems with the selected encoding settings. All messages displayed by the settings advisor are flagged to indicate the severity of the message. Error Job cannot run using the current settings. You must correct the problem before the job will start. Warning Selected settings do not comply with standards. The job will run but the encoded content may not play on some media players. Information Selected settings do not comply with best practices. However, the encoded content is likely to play on most media players. Note: Click the question mark icon ( ) to the right of the message to display detailed information about the problem. Tip: Click Settings Advisor on the toolbar to toggle the display of the settings advisor. 130

139 Part V: APPENDIXES PART V The following appendixes contain useful reference information.

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141 Appendix A: PREFERENCES APPENDIX A The RealProducer preferences affect the operation of both the graphical application and the command-line application. Preferences File RealProducer records application preferences in the file producer.pref, located in the main installation directory. This text file specifies values such as the temporary directory, encoding defaults, and tolerance levels for audio and video warnings. Using the graphical application, you can edit the preferences by selecting the File>Preferences menu entry. Note: You must restart RealProducer to put preference changes into effect. File Location Preferences Choose Edit>Preferences and click the File Locations tab to set the directory paths for certain files used by RealProducer. File Location Preferences 133

142 RealProducer User s Guide Template Directories The Audience and Server fields specify the locations of the templates that hold encoding and broadcast parameters, respectively. You typically do not need to change the template locations unless you want to move template files to a common location shared by multiple installations of RealProducer. By default, these templates are stored in the audiences and servers directories of the main installation directory. To change the locations, click the Open buttons and navigate to the appropriate directories on your file system. Temporary Directory Note: You must copy the existing template files to the new template directories manually. Restart RealProducer to put the changes into effect. For More Information: See Audience Templates on page 51 and Server Destination Templates on page 104. RealProducer uses the temporary directory to write temporary data when encoding on-demand clips. It deletes the temporary files after it has fully encoded the output clip. Output File Directory Click the Same Location as Destination File radio button to write temporary data to the same directory that will hold the output file. This is recommended only if you write output files to the local disk on the RealProducer machine. The encoding process may slow down if you write temporary data to a networked, shared directory. Specific Directory Click the Other radio button and then the Open button to select a specific directory to use as the temporary directory. To use the same directory specified by the Windows TEMP variable, enter the following in the field: %TEMP% 134

143 APPENDIX A: Preferences Log File Preferences Click Edit>Preferences and choose the File Logging tab to set the RealProducer logging preferences. These preferences affect how both the command-line application and the graphical application log encoding events. Logging Preferences Tip: Logging is enabled automatically. You can disable it by editing the producer.pref file directly. For more information, see the preferences appendix of RealProducer Command Line and Job File Reference. Log File Location Logging Settings The standard log file is a text file named producer.log that resides in the main installation directory. Click the Open button to navigate to a different directory. You can change the file name directly in the preferences field after you select the new directory. The options in the Logging Settings section allow you to set the basic logging choices. Message Format For Message Format, choose one of the following: 135

144 RealProducer User s Guide Detailed Record full information, such as the message category, functional area, time, and message number. short Record only the job name and message. Message Severity In the Message Severity section, you can select up to four logging categories. Choose any combination of the following: Errors Warnings Information Diagnostic Error messages indicate significant problems that have occurred in the encoding process. These problems typically caused the encoding process to fail. The problem must be corrected for encoding to continue. Warning messages indicate possible problems in the encoding process. For example, RealProducer logs a warning if its audio watchdog detects that stereo input channels are out of balance. Warning messages also alert you to encoding settings that may make the stream unplayable on certain media players. Informational messages provide important but non-critical information about the encoding operation. They also alert you to encoding settings that do not follow best practices. Diagnostic messages convey non-critical messages about RealProducer operation. Because an encoding operation may generate many diagnostic messages, the log file can grow rapidly if you include the Diagnostic category. Functional Area Each message is part of a functional area. For example, messages concerning audio codec operation fall under the Audio Codec area. Each functional area may include errors, warnings, informational messages, and diagnostic messages. Under Functional Area, select the functional area messages that you want to log in the log file. Functional Area ActiveX Audio Codec Logging Functional Areas Events Logged Events specific to the ActiveX control used by Windows-based programs to encode media using RealProducer. Events involving an audio codec used for the job. For details about setting audio codecs, refer to Audio Encoding Settings on page

145 APPENDIX A: Preferences Functional Area Audio Prefilters Broadcast Capture Command Line File Output File Reader GUI Job File Postfilters Remote Agent SDK Configuration SDK Encoding SDK Core SDK Generic Filter Statistics Video Codec Video Pre-filters Video Rendering Logging Functional Areas Events Logged Events concerning the use of an audio prefilter. See Audio and Video Preprocessing on page 37. Events that occur when transmitting a live stream to Helix Server. For an introduction to broadcast issues, refer to Live Broadcasting on page 87. Events around the capture of input media. See Capture Input on page 29 for capture setup instructions. Events that occur when running the command-line application. The document RealProducer Command Line and Job File Reference explains the use of this application. Events involved with writing encoded media streams to a file. The section Output File Destination on page 55 explains how to set up a file as the output. Events related to reading an audio or video file. Events related to the use of the graphical application. Events related to the use of a job file. Events related to post-filters added by the RealProducer SDK. Events related to the remote agent. Events concerning the set up of jobs. Events related to encoding activities. Events specific to the core SDK. General events about prefilters or postfilters. Events that affect statistics processing. Events related to the video codec. Events concerning the use of a video prefilter. Events related to video preview. Log File Rolling The log rolling feature creates a new log file when the current log file reaches a certain size or time limit. Using log rolling is recommended if you encode many streams or capture diagnostic messages to the log file. To set up log file rolling, click the Enable Log File Rolling box. Then choose the criterion for rolling the log file: 137

146 RealProducer User s Guide Log Size To create a new log file when the current file reaches a certain size, select the Roll File Every radio button. Then choose a file size in Megabytes. Log Time To create a new log file at a regular interval, click the Roll at End of Every radio button. Then select Hour, Day, Week, or Month. Tip: The active log file is always the name you define in the Log File Location field. Archived log files have an integer value appended to their file extensions, such as producer.log1 and producer.log2. Lower numbers indicate earlier archives. Output Preferences Click Edit>Preferences and choose the Output Settings tab to set default encoding settings such as the audience template used. This is useful if you repeatedly encode the same clip or broadcast, such as a program updated every hour. When you create a new job, RealProducer automatically fills in the appropriate fields of the Output tab with the default values. Output Preferences 138

147 APPENDIX A: Preferences Encoding Defaults For Encoding Settings, you can pick one or more audiences used to encode the output stream, whether a clip or a live broadcast. Click the Open button to display the templates dialog. Next, select one or more audiences. For More Information: See Audience Templates on page 51. Output Directory and File Name Defaults The Output Filename field defines a standard file name and output directory for encoded clips. If you want to define a directory where all encoded files are written, click the Open button and select the directory. Alternatively, you can define file path variables. File Name and Path Variables For the output file name and path, you can use any of the following variables. RealProducer then substitutes the appropriate value when it runs the job. %InputFilename% The input file name without the path or file extension. %InputFilePath% The input file's absolute directory path without the file name or extension. %OutputName% The output name. See Output Name on page 50. %OutputTypeExt% The default file extension for the output type: rm. Example of Input File Directory and Output File Name The following values writes the output file to the same directory that holds the input file: %InputFilePath%\%OutputName%.%OutputTypeExt% The file name is the output name selected on the Output tab (see Output Name on page 50) along with the appropriate file extension. Output Server Defaults For Output Servers, you can select a server destination template used by default. This is useful if you always deliver broadcasts of this media type using the same server. Click the Open button and select one of the destination templates. 139

148 RealProducer User s Guide Metadata Defaults For More Information: See Server Destination Templates on page 104. The Metadata fields allow you to define a standard set of metadata values for each output. You can define some or all values. For example, you might set only a default copyright date and author string for each stream. For More Information: Refer to Metadata Titles and Values on page 58. Signal Detection Preferences The preferences (File>Preferences) on the AV Signal Detection tab affect audio and video tests run during the encoding process. These tests write warnings to the log file if RealProducer detects problems with the incoming audio or video stream. This is useful with live input to indicate problems with capture cards, cabling, cameras, microphones, and so on. Signal Detection Preferences Tip: Typically, you can leave these values set to their defaults, changing them only if erroneous error messages are written to the log file. 140

149 APPENDIX A: Preferences Audio Watchdog Tests Click the Enable Audio Watchdogs box to run the audio watchdogs for all encoding jobs. You can then adjust the tolerances, if necessary, for each audio test. Silence The Silence test warns if the audio signal does not rise above a certain decibel setting for a certain period. You can set the decibel level and the required duration. Silence Level In digital audio signals, 0 db represents the maximum audio level. Each decrease of 6 decibels indicates a reduction in the audio level by half. The default value of -60 represents a complete loss of the audio signal. Tip: Select a level in decibels high enough to distinguish between background noise and true silence. In clean audio feeds, noise levels are low, and you can set this value low. For noisier feeds, such as those originating from analog sound cards, a low value may incorrectly identify noise as an active audio signal. Silence Duration You can specify a period in seconds over which this condition must persist to be considered an error. This screens out normal audio lapses, such as when cutting to a commercial break. The default is 10 seconds. Channel Imbalance A channel imbalance occurs when one of the stereo channels is six decibels higher or lower than the other channel. The audio watchdog issues a warning if this condition persists for a certain period. The default is 10 seconds. Clipping Clipping occurs when the audio peak reaches 0 decibels (maximum level). At this point, distortion typically occurs. This audio watchdog warns that the audio is being clipped heavily, moderately, or lightly. You can specify a period in seconds over which this condition must persist. The default is 10 seconds. 141

150 RealProducer User s Guide Out of Phase This warning is logged if the left and right channels of a stereo signal are out of phase. You can specify a period in seconds over which this condition must persist. The default is 10 seconds. Video Watchdog Tests Click the Enable Video Watchdogs box to run the video watchdogs for all encoding jobs. You can then adjust the tolerances, if necessary, for the video watchdog tests. No Signal (Single Color Image) The No Signal test detects that the video image is a single, unchanging color. This typically indicates the lack of a video signal. Note: This test does not identify color bars in the video stream. No Signal Complexity Value For the No Signal test, you can set a complexity value used to identify if a video frame is a solid color. The complexity value ranges from 0 (solid color) to 100 (white noise). The default is 5. Tip: Lower the value if warnings about missing signals are consistently reported for video streams that are OK. Raise the value if missing signal conditions are underreported. No Signal Duration You can also set a duration that defines how long the No Signal condition can occur before a warning is logged. The default value is 10 seconds. Noisy Signal (White Noise) The Noisy Signal test detects white noise. This condition occurs when the video receiver cannot find a signal and reads background noise. Noisy Signal Complexity Value The Noisy Signal test has a complexity value used to identify if a video frame is white noise. The complexity value ranges from 0 (solid color) to 100 (white noise). The default is

151 APPENDIX A: Preferences Tip: Raise the value if white noise warnings are consistently reported for video streams that are OK. Lower the value if white noise conditions are underreported. Noisy Signal Duration You can also set a duration that defines how long the Noisy Signal condition can occur before a warning is logged. The default value is 10 seconds. Frozen Signal (Color Bars) The Frozen Signal test warns that the video image has not changed. This condition can occur if the image is frozen or the video output displays color bars. Frozen Signal Complexity Value The Frozen Signal test sets a factor used to gauge if video frames are changing. The default is 0.5. Tip: Lower the value if frozen signal warnings are consistently reported for video streams that are OK. Raise the value if frozen signals are underreported. Frozen Signal Duration You can also set a duration that defines how long the Frozen Signal condition can occur before a warning is issued. The default value is 10 seconds. Message Suppression Audio and video watchdog messages can rapidly fill the log file if the problems persist. To cut down on the number of messages, enter a value in minutes in the Suppress duplicated messages for... field. A value of 5, for example, means that each warning is reported every five minutes as long as the condition persists. Frame Analysis Period The value for the last field on this preferences tab determines how frequently the video watchdog tests run. Limiting the tests to once every 30 seconds, for example, helps to minimize CPU usage. 143

152 144 RealProducer User s Guide

153 Appendix B: AUDIENCE TEMPLATES APPENDIX B Information in this appendix will help you to choose which audiences to use when encoding a clip or broadcast. Predefined Audience Templates An audience template defines a range of parameters used to encode a clip or broadcast. For example, it defines the audio and video codec, along with the streaming bandwidth. RealProducer provides a number of predefined templates stored as files (file extension.rpad) in its audiences subdirectory. Templates Included with RealProducer Most predefined video templates are available in three versions: RealVideo, H.263, and H.264. Audio-only templates are available for RealAudio, AAC, AAC+, and MP3. Note: H.264, H.263, AAC, AAC+, and MP3 templates do not function with RealProducer. Audio-Only Templates The audio-only templates are for CBR audio output. They do not define any video settings: 16k Voice 32k Music 64k Music 96k Music Tip: You can also use a video template to encode an audio-only output. RealProducer simply ignores the video settings. 145

154 RealProducer User s Guide Video Templates (CBR) Constant bit rate video templates define settings for streaming video and audio: 28k Video 56k Video 65k Video 80k Video 100k Video 150k Video 300k Video 750k Video 1.5M Video Tip: You can add multiple CBR audiences to the same output to create a rate-shifting stream. VBR Quality Template The variable bit rate template is designed for downloadable video clips in the RealMedia format: 90% VBR Quality Video Customized Templates Note: A VBR clip can encode only one audience. RealProducer offers many more encoding choices than those available using the predefined templates. In many cases, you ll want to create your audience templates that cover your specific encoding needs. To do this, start with the predefined template that is closest to your desired output. Then edit the template using RealProducer. When it has the new settings you want, save the template under a new name. 16k Voice The 16 Kb audio audiences target low-bandwidth, audio-only streaming of voice content (no music). There are three predefined audiences: 146

155 APPENDIX B: Audience Templates 16k R5 Voice.rpad 3GPP Release 5, 3GPP Release 6, or MPEG-4 16k R6 Voice.rpad 3GPP Release 6 or MPEG-4 16k RA Voice.rpad RealAudio The following table lists the encoding settings for these audiences. 16k Audio Audience Settings Setting 16k R5 16k R6 16k RA Audio bandwidth 12.2 Kbps Kbps 16 Kbps Audio codec AMR-NB AMR-WB RealAudio Voice Audio channels Rate control type CBR CBR CBR 28k Video The 28 Kb video audiences target low-bandwidth video streaming. There are three predefined audiences: 28k H.263.rpad 3GPP Release 5, 3GPP Release 6, or MPEG-4 28k H.264.rpad 3GPP Release 6 or MPEG-4 28k RV.rpad RealVideo The following table lists the encoding settings for these audiences. 28k Video Audience Settings Setting 28k H k H k RV Video average bandwidth 20 Kbps 20 Kbps 20 Kbps Audio bandwidth 8 Kbps 8 Kbps 6 Kbps Audio codec AAC-LC AAC+ RealAudio Audio channels Video codec H.263 H.264 RealVideo 10 Video profile 0 Baseline NA Video level auto auto NA Maximum video frame rate (fps) Preroll (buffering time) 1 second 1 second 4 seconds Quality

156 RealProducer User s Guide 28k Video Audience Settings Setting 28k H k H k RV Encoding complexity high high high Rate control type CBR CBR CBR 32k Music The 32 Kb audio audiences target low-bandwidth, audio-only streaming of music. There are four predefined audiences: 32k MP3 Music.rpad MP3 32k AAC Music.rpad 3GPP Release 5, 3GPP Release 6, or MPEG-4 32k AAC+ Music.rpad 3GPP Release 6 or MPEG-4 32k RA Music.rpad RealAudio The following table lists the encoding settings for these audiences. 32k Audio Audience Settings Setting 32k MP3 32k AAC 32k AAC+ 32k RA Audio bandwidth 32 Kbps 32 Kbps 32 Kbps 32 Kbps Audio codec MP3 AAC-LC AAC+ RealAudio Audio channels Rate control type CBR CBR CBR CBR 56k Video The 56 Kb video audiences target low-bandwidth video streaming. There are three predefined audiences: 56k H.263.rpad 3GPP Release 5, 3GPP Release 6, or MPEG-4 56k H.264.rpad 3GPP Release 6 or MPEG-4 56k RV.rpad RealVideo 148

157 APPENDIX B: Audience Templates The following table lists the encoding settings for these audiences. 56k Video Audience Settings Setting 56k H k H k RV Video average bandwidth 44 Kbps 44 Kbps 44 Kbps Audio bandwidth 12 Kbps 12 Kbps 12 Kbps Audio codec AAC-LC AAC+ RealAudio Audio channels Video codec H.263 H.264 RealVideo 10 Video profile 0 Baseline NA Video level auto auto NA Maximum video frame rate (fps) Preroll (buffering time) 1 second 1 second 4 seconds Quality Encoding complexity high high high Rate control type CBR CBR CBR 64k Music The 64 Kb audio audiences target low-bandwidth, audio-only streaming of music. There are four predefined audiences: 64k MP3 Music.rpad MP3 64k AAC Music.rpad 3GPP Release 5, 3GPP Release 6, or MPEG-4 64k AAC+ Music.rpad 3GPP Release 6 or MPEG-4 64k RA Music.rpad RealAudio The following table lists the encoding settings for these audiences. 64k Audio Audience Settings Setting 64k MP3 64k AAC 64k AAC+ 64k RA Audio bandwidth 64 Kbps 64 Kbps 64 Kbps 64 Kbps Audio codec MP3 AAC-LC AAC+ RealAudio Audio channels Rate control type CBR CBR CBR CBR 149

158 RealProducer User s Guide 65k Video The 65 Kb video audiences target low-bandwidth video streaming. There are three predefined audiences: 65k H.263.rpad 3GPP Release 5, 3GPP Release 6, or MPEG-4 65k H.264.rpad 3GPP Release 6 or MPEG-4 65k RV.rpad RealVideo The following table lists the encoding settings for these audiences. 65k Video Audience Settings Setting 65k H k H k RV Video average bandwidth 53 Kbps 53 Kbps 53 Kbps Audio bandwidth 12 Kbps 12 Kbps 12 Kbps Audio codec AAC-LC AAC+ RealAudio Audio channels Video codec H.263 H.264 RealVideo 10 Video profile 0 Baseline NA Video level auto auto NA Maximum video frame rate (fps) Preroll (buffering time) 1 second 1 second 4 seconds Quality Encoding complexity high high high Rate control type CBR CBR CBR 80k Video The 80 Kb video audiences target medium-bandwidth video streaming. There are three predefined audiences: 80k H.263.rpad 3GPP Release 5, 3GPP Release 6, or MPEG-4 80k H.264.rpad 3GPP Release 6 or MPEG-4 80k RV.rpad RealVideo 150

159 APPENDIX B: Audience Templates The following table lists the encoding settings for these audiences. 80k Video Audience Settings Setting 80k H k H k RV Video average bandwidth 64 Kbps 64 Kbps 64 Kbps Audio bandwidth 16 Kbps 16 Kbps 16 Kbps Audio codec AAC-LC AAC+ RealAudio Audio channels Video codec H.263 H.264 RealVideo 10 Video profile 0 Baseline NA Video level auto auto NA Maximum video frame rate (fps) Preroll (buffering time) 1 second 1 second 4 seconds Quality Encoding complexity high high high Rate control type CBR CBR CBR 96k Music The 96 Kb audio audiences target high-bandwidth, audio-only streaming of music. There are four predefined audiences: 96k MP3 Music.rpad MP3 96k AAC Music.rpad 3GPP Release 5, 3GPP Release 6, or MPEG-4 96k AAC+ Music.rpad 3GPP Release 6 or MPEG-4 96k RA Music.rpad RealAudio The following table lists the encoding settings for these audiences. 96k Audio Audience Settings Setting 96k MP3 96k AAC 96k AAC+ 96k RA Audio bandwidth 96 Kbps 96 Kbps 96 Kbps 96 Kbps Audio codec MP3 AAC-LC AAC+ RealAudio Audio channels Rate control type CBR CBR CBR CBR 151

160 RealProducer User s Guide 100k Video The 100 Kb video audiences target high-bandwidth video streaming. There are three predefined audiences: 100k H.263.rpad 3GPP Release 5, 3GPP Release 6, or MPEG-4 100k H.264.rpad 3GPP Release 6 or MPEG-4 100k RV.rpad RealVideo The following table lists the encoding settings for these audiences. 100k Video Audience Settings Setting 100k H k H k RV Video average bandwidth 80 Kbps 80 Kbps 80 Kbps Audio bandwidth 20 Kbps 20 Kbps 20 Kbps Audio codec AAC-LC AAC+ RealAudio Audio channels Video codec H.263 H.264 RealVideo 10 Video profile 0 Baseline NA Video level auto auto NA Maximum video frame rate (fps) Preroll (buffering time) 1 second 1 second 4 seconds Quality Encoding complexity high high high Rate control type CBR CBR CBR 150k Video The 150 Kb video audiences target high-bandwidth video streaming. There are three predefined audiences: 150k H.263.rpad 3GPP Release 5, 3GPP Release 6, or MPEG-4 150k H.264.rpad 3GPP Release 6 or MPEG-4 150k RV.rpad RealVideo 152

161 APPENDIX B: Audience Templates The following table lists the encoding settings for these audiences. 150k Video Audience Settings Setting 150k H k H k RV Video average bandwidth 122 Kbps 122 Kbps 118 Kbps Audio bandwidth 28 Kbps 28 Kbps 32 Kbps Audio codec AAC-LC AAC+ RealAudio Audio channels Video codec H.263 H.264 RealVideo 10 Video profile 0 Baseline NA Video level auto auto NA Maximum video frame rate (fps) Preroll (buffering time) 1 second 1 second 4 seconds Quality Encoding complexity high high high Rate control type CBR CBR CBR 300k Video The 300 Kb video audiences target high-bandwidth video streaming. There are three predefined audiences: 300k H.263.rpad 3GPP Release 5, 3GPP Release 6, or MPEG-4 300k H.264.rpad 3GPP Release 6 or MPEG-4 300k RV.rpad RealVideo The following table lists the encoding settings for these audiences. 300k Video Audience Settings Setting 300k H k H k RV Video average bandwidth 244 Kbps 252 Kbps 256 Kbps Audio bandwidth 56 Kbps 48 Kbps 44 Kbps Audio codec AAC-LC AAC+ RealAudio Audio channels Video codec H.263 H.264 RealVideo 10 Video profile 0 Baseline NA 153

162 RealProducer User s Guide 300k Video Audience Settings Setting 300k H k H k RV Video level auto auto NA Maximum video frame rate (fps) Preroll (buffering time) 1 second 1 second 4 seconds Quality Encoding complexity high high high Rate control type CBR CBR CBR 750k Video The 750 Kb video audience targets medium-quality video downloading. There are two predefined audiences: 750k H.264.rpad 3GPP Release 6 or MPEG-4 750k RV.rpad RealVideo The following table lists the encoding settings for these audiences. 750k Video Audience Settings Setting 750k H k RV Maximum bandwidth 686 Kbps 686 Kbps Video average bandwidth 686 Kbps 686 Kbps Audio bandwidth 48 Kbps 64 Kbps Audio codec AAC+ RealAudio Audio channels 2 2 Video codec H.264 RealVideo 10 Video profile Baseline NA Video level auto NA Maximum video frame rate (fps) Preroll (buffering time) 1 second 4 seconds Quality Encoding complexity high high Rate control type CBR VBRBitrate 154

163 APPENDIX B: Audience Templates 1.5M Video The 1.5 Mb video audience targets high-quality video downloading. There are two predefined audiences: 1.5M H.264.rpad 3GPP Release 6 or MPEG-4 1.5M RV.rpad RealVideo The following table lists the encoding settings for these audiences. 1.5M Video Audience Settings Setting 1.5M H M RV Maximum bandwidth Mbps Mbps Video average bandwidth Mbps Mbps Audio bandwidth 96 Kbps 96 Kbps Audio codec AAC+ RealAudio Audio channels 2 2 Video codec H.264 RealVideo 10 Video profile Baseline NA Video level auto NA Maximum video frame rate (fps) Preroll (buffering time) 1 second 4 seconds Quality Encoding complexity high high Rate control type CBR VBRBitrate 90% VBR Quality Video The 90% VBR Quality video audience targets high-quality video downloading. It attempts to preserve near-perfect video quality within the constraints of maximum bandwidth, frame size, and video content. There is one predefined audience: 90% VBR Quality RV.rpad RealVideo 155

164 RealProducer User s Guide The following table lists the encoding settings for this audience. 1.5M Video Audience Settings Setting 90% RV Maximum bandwidth 2 Mbps Video average bandwidth 2 Mbps Audio bandwidth 96 Kbps Audio codec RealAudio Audio channels 2 Video codec RealVideo 10 Video profile NA Video level NA Maximum video frame rate (fps) 30 Preroll (buffering time) 4 seconds Quality 90 Encoding complexity high Rate control type VBRQuality 156

165 Appendix C: AUDIO AND VIDEO TIPS APPENDIX C This appendix provides tips for capturing and editing audio and video input. This information will help you to encode higher-quality output streams. Audio Capture Source Media A streaming clip reflects the quality of its audio source. Any quality problems within the source will affect the streaming clip as well. Because you cannot edit a broadcast, live Webcasting introduces several issues beyond those involved with delivering on-demand clips. This section will help you capture high-quality audio source files, or set up your sound equipment to deliver good broadcasts. If you plan to stream existing material, start with the best source possible. Use the cleanest recording with the least amount of unwanted noise. CDs, DVDs, and digital audio tapes (DATs) are good source media. Well-recorded analog sources such as records, reel-to-reel tapes, and chrome (Type II) cassettes can also sound good. Avoid consumer-grade recording media such as Type I cassettes and VHS tapes. Recording Equipment Every piece of equipment in the audio chain microphone, mixer, sound card, and so on affects sound quality. If you intend to provide professional-quality audio content, invest in professional-quality audio equipment and software. Lesser equipment can add hiss and distortion, degrading sound clarity. 157

166 RealProducer User s Guide Shielded Cables Input Levels It is important to use high-quality, shielded cables. Using unshielded cables increases the likelihood of introducing line noise and radio frequency interference into recordings. Keep audio cables physically separated from power cords to minimize the introduction of noise. Also be sure to ground all equipment properly. Setting correct input levels is crucial. All audio equipment has a dynamic range, the ratio between the loudest possible sound the equipment can reproduce without distortion and its inherent noise floor. Also called clipping, distortion of this type is audible as a high-frequency crackling noise. To get the best dynamic range, set the input level on each audio device in the signal chain so that it uses its full range of available amplitude without distortion during the program s loudest sections. The signal chain typically includes a microphone, a mixing desk, a compressor, and a sound card. For each piece of equipment, set levels as close as possible to 0 decibels without going over that level. Check for signal distortion at each point in the signal chain. Perform several test runs, and make sure that there are no peaks above maximum amplitude. Adjust the levels on your sound card mixer so that the input approaches but does not exceed the maximum. Be conservative, though. Levels might suddenly increase if, for instance, an interviewee suddenly speaks loudly or a crowd at a sports event roars. Volume Levels for Live Broadcasts Sampling Rates When broadcasting live audio streams, it is useful to have a dynamics compressor for gain compression (not data compression). This piece of audio equipment automatically adjusts the volume level. By providing a consistent volume level, it allows you to set and forget the input levels to RealProducer. Try to capture sound with a sampling width of 16 bits. RealAudio codecs have different sampling rates that produce the best sound, however. If your sound card allows it, capture audio content at the optimum sampling rate for the 158

167 APPENDIX C: Audio and Video Tips codec you intend to use. RealProducer will convert the file to the optimum rate if necessary, but this is recommended only for static files. For live broadcasts, use a sound card that supports the optimum rate. This avoids the overhead entailed in converting the rate while encoding sound in real time. Tip: You do not need to capture stereo sound if you plan to use a mono codec. However, many sound cards simply discard the right input channel in mono mode. If you have a mixing desk, pan all inputs to the center so that nothing is lost during the conversion to mono. Audio Optimization DC Offset Normalization If you are not broadcasting audio live, you typically start with digitized audio source files in supported input formats, such as WAV. Although RealProducer can adjust audio levels during encoding, you achieve the best quality for editing files before encoding them. To optimize audio files this, you need to be familiar with the features your editing program offers. This section gives you some optimization tips you can try with your editing software before encoding your clips with RealProducer. Tip: Always keep copies of your audio source files. You cannot convert encoded clips back to their original source formats. DC offset is low-frequency, inaudible noise that results from equipment grounding problems. If you don t remove it, it can skew the results of subsequent sound editing. Use your sound editor s DC Offset function immediately after recording a digital audio file. Tip: If your editing program has this option, remove DC offset during recording. This eliminates an editing step. Set sensible input levels when recording, and then use normalization to maximize the levels after recording. Your streaming files sound best when your digitized source has the highest possible gain without clipping. Digital audio files that do not use their full amplitude range produce low-quality 159

168 RealProducer User s Guide streaming clips. If the amplitude range is too low, use your sound editor to adjust the range and increase the amplitude. Dynamics Compression Equalization Tip: Most sound editors have a Normalize function that maximizes levels automatically. Because some systems have trouble with files normalized to 100 percent, normalize to 95 percent of maximum, or to -0.5dB. Normalization maximizes the volume level of the audio file s loudest sections. Consequently, quiet sections may not encode as well. Dynamics compression evens out input levels by attenuating (turning down) the input when it rises above a specified threshold. Check your audio software for a Compression or Dynamics feature. You can control attenuation by specifying a compression ratio. This turns down the loudest sections, and you can readjust input levels accordingly. Tip: For multipurpose dynamics compression, set the threshold to -10dB, the ratio to 4:1, and the attack and release times to 100ms. Adjust the input level to get approximately 3dB of compression and an output level of about 0dB. Equalization (EQ) changes the tone of the incoming signal by boosting (turning up) or cutting (turning down) certain frequencies. Using EQ, you can emphasize certain frequencies and cut others that contain noise or unwanted sound. EQ can compensate for codecs that do not have flat frequency responses (that is, codecs for which certain frequencies are not as loud after encoding). You can therefore use EQ to make an encoded audio clip sound as close as possible to the source recording. Tip: For voice-only content, you can make the file more intelligible by cutting frequencies below 100 Hz and carefully boosting frequencies in the 1000 to 4000 Hz range. 160

169 APPENDIX C: Audio and Video Tips Video Recording Video Staging If you intend to shoot a new video rather than use existing video content, this section provides tips for capturing high-quality input. Because video loses image quality if it s highly compressed, always start with the best video source available. For More Information: For pointers on recording audio, see Audio Capture on page 157. Consider the video s final frame size before you shoot the first frame. Streaming over a slow data connection requires a small video window, so you need to frame important visual elements well. For recommended clip dimensions, see Frame Size on page 72. Scene Changes and Movement The fewer things that change from frame to frame, the sharper the image will appear in a low-bandwidth video. You can do the following to cut down on unnecessary movement: Use a mounted camera rather than hand-held one. This greatly reduces the movement you inadvertently introduce into the scene when recording. Don t have a rapidly moving object fill the entire frame. But you don t want to pull the camera back too far either. You need to find a happy medium between close-ups and panoramic shots. Of course, you don t want to eliminate all dynamic elements. When you do include rapid movement, allow enough time for objects to resolve. Because of low frame rates and high compression, objects coming to rest may appear blurry at first. If you have a dialog box popping up on a computer screen, for example, have the box remain stationary for a few seconds so that the image resolves. Colors and Lighting Bright lighting at a constant exposure keeps the foreground detail crisp. Use uniformly dark colors for backgrounds, and uniformly light colors (but not whites) for clothing. Complex textures such as paisley and stripes degrade the final image quality with unwanted visual effects. 161

170 RealProducer User s Guide Video Output Color Depth Video playback devices commonly have at least two common output types S-video and composite. Use S-video, as it produces better results. Professional-grade devices typically have other, high-quality output modes that can connect to a video capture card. Always use 24-bit or 32-bit color. Lower color resolution results in poor clips. Source Media Quality Whether you shoot a video yourself or digitize existing material, start with high-quality video media. The following are common video formats, listed in order of descending quality: 1. HDV 2. Betacam SP, also known simply as Beta. This format is common among video production professionals. 3. DV, minidv, DVCam, or DVCPro. 4. Super-VHS (S-VHS) or HI-8mm. 5. VHS, 8mm. 162

171 INDEX A arch file name addition, 55 archiving broadcasts, 100 audience templates 1.5M Video, k Video, k Video, k Audio, k Video, k Video, k Audio, k Video, k Audio, k Video, k Video, k Video, % Quality Video, k Audio, 151 ocation, 134 predefined files, 145 audiences adding to output, 51 customizing, 52 templates deleting, 54 saving as, 53 audio cables, 158 capture, 29 channels, 64 codec choice, 64 customization, 63 DC offset, 159 digitizing, 159 dynamics compression, 160 equipment quality, 157 filters, 37 frequency equalization, 160 B gain, 38, 158 input formats, 11 input levels, 158 mixer, 30 monitoring levels, 127 muting, 38 normalization, 159 optimizing, 159 recording tips, 157 resampling while broadcasting, 68 sampling rates choosing, 68 for codecs, 13 sampling width, 158 signal detection, 141 signal-to-noise ratio, 158 source media, 157 synchronizing with video, 39 vendor controls, 30 bandwidth negotiation, 18 rate-shifting clips, 18 Betacam video, 162 black-level correction, 46 broadcasting archive clip, 87 audio resampling, 68 audio volumes, 158 broadcast quality, 88 encoder redundancy, 97 forward error correction, 98 from a file, 87 IP version 6, 101 redundant stream protection, 99 TCP transport, 97 trial run,

172 RealProducer User s Guide UDP transport, 97 video startup latency, 83 see also Helix Push broadcast see also Helix Multicast Push broadcast see also Helix Advanced Push broadcast see also Helix Pull broadcast C cable shielding, 158 channel imbalance detection, 141 clipping detection, 141 color bar detection, 143 D de-interlace filter, 42 digital video formats, 162 DirectX requirements, 11 discrete multichannel audio description, 66 encoding with stereo codecs, 67 sound system requirements, 67 supported number of channels, 67 dynamics compression, 160 F file input, 27 film-to-video transfer, 42 firewall problems during broadcasts, 109, 113 forward error correction, 98 frame rates when capturing video, 33 see also video H hardware requirements, 7 Helix Advanced Push broadcast advantages of, 91 archiving, 111 broadcast steps, 91 metadata resend interval, 113 overview, 110 redundant encoders, 111 server authentication, 112 destination, 110 ports used, 112 stream name, 111 URLs, 92 Helix Multicast Push broadcast archiving, 116 metadata resend interval, 118 multicast address, 116 packet TTL, 117 server authentication, 116 ports used, 116 stream name, 115 URLs, 93 Helix Pull broadcast advantages of, 94 archiving, 120 broadcasting steps, 94 outgoing bandwidth, 95 overview, 118 server authentication, 121 ports used, 120 stream acquisition latency, 95 stream name, 120 URLs, 95 Helix Push broadcast archiving, 106 broadcast steps, 89 overview, 89 ports data, 107 HTTP, 107 redundant encoders, 107 server authentication, 107 destinations, 105 statistics update interval, 109 stream name, 106 URLs, 90 I Input tab, 25 inputs audio formats accepted, 11 file selecting, 27 start and stop times, 33 live capture,

173 Index J audio controls, 30 audio mixer, 30 duration, 29 frame rate, 33 video dimensions, 32 source properties, 35 video formats accepted, 11 installation Windows, 7 interlaced video, 42 inverse-telecine filter, 42 IP addresses version 6, 101 job file creating, 26 opening, 27 samples, 26 saving, 26 syntax, 26 upgrading, 27 jobs, 126 K key frames, 82 L log viewer, 129 logging category, 136 disabling, 135 file name, 135 file rolling enabling, 137 file size, 138 interval, 138 format, 135 functional areas, 136 message severity, 136 M metadata, 57 Monitoring tab, 125 mono audio encoding, 64 multicasting overview, 114 packet time to live (TTL), 117 multichannel audio see discrete multichannel audio see stereo surround N NAT firewall traversal, 109, 113 O OpenDML, 28 output file, 55 Output tab, 47 outputs defining, 49 monitoring, 127 P packet time to live, 117 phase balance detection, 142 pixel aspect ratio, 45 preferences audio signal detection, 140 file paths, 133 logging, 135 preference file, 133 video signal detection, 140 prefilters audio gain, 38 audio synchronization, 39 black-level correction, 46 de-interlace, 42 input cropping, 39 inverse-telecine, 42 noise, 43 resize, 44 Q QuickTime input sources, 12 R rate control clip encoding requirements, 19 codec choice, 20 downshifting and upshifting, 19 encoding times, 18 multi-rate clips, 18 rate-shifting clips, 19 streaming rates, 20 rate shifting, 19 RealAudio 165

174 RealProducer User s Guide S choosing, 64 codecs discrete multichannel, 16 high response, 14 mono music, 15 stereo music, 15 stereo surround, 16 voice, 13 converting to other formats, 159 overview, 13 RealVideo codecs RealVideo 10, 17 RealVideo 8, 18 RealVideo 9, 17 compressed input, 11 converting to other formats, 11 file rolling, 57 frame rate mode, 76 overview, 17.rmvb extension, 17 sampling rates setting, 68 server destinations, 104 Helix Advanced Push broadcast, 110 Helix Multicast Push broadcast, 114 Helix Pull broadcast, 118 Helix Push broadcast, 105 saving as templates, 105 template location, 134 settings advisor, 130 shielded cables, 158 silence detection, 141 source properties, 35 stereo audio encoding, 64 stereo surround encoding as standard stereo, 66 overview, 65, 66 sources for, 65 supported number of channels, 65 SureStream, see rate control s-video, 162 T tabs input, 25 monitoring, 125 output, 47 XML, 26 TCP transport, 97 temporary directory, 134 two-pass encoding, 56 U UDP transport, 97 V variable bit rate encoding, 78 maximum bit rate, 79 quality, 80 VHS format, 162 video advanced settings, 77 artifacts, 43 average bit rate, 70 black-level correction, 46 capture, 29 disk space, 28 file size limit, 28 formats, 11 frame rates, 33 requirements, 28 cropping, 39 effect on broadcasts, 39 dimensions desktop media, 75 portable devices, 72 resizing methods, 73 encoding complexity, 75 filters, 37 frame rates factors that affect, 71 variable nature, 71 frame size multi-rate streams, 21 setting, 72 input formats, 11 interlaced, 42 key frame maximum benefits of lowering, 82 costs of lowering,

175 Index overview, 82 lighting, 161 minimizing movement, 161 motion resolution, 161 noise reduction, 43 preroll setting, 81 recording tips, 161 resize quality, 73 resizing, 44 resizing output, 72 source formats, 162 staging shots, 161 s-video, 162 synchronizing with audio, bit depth, 162 variable bit rate encoding, 78 Video for Windows, 11 video stream, 143 signal detection, 142 white noise detection, 142 volume for live broadcasts, 158 W white noise detection, 142 Windows installation, 7 X XML tab,

176 168 RealProducer User s Guide