MPEG, the MP3 Standard, and Audio Compression

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "MPEG, the MP3 Standard, and Audio Compression"

Transcription

1 MPEG, the MP3 Standard, and Audio Compression Mark ilgore and Jamie Wu Mathematics of the Information Age September 16, 23 Audio Compression Basic Audio Coding. Why beneficial to compress? Lossless versus Lossy Compression. How are MP3s Compressed? What makes MP3 Compression Different? What other formats lie in our future? 1

2 PCM Why Compress?? Eliminate redundancy Most basic encoder/decoder is PCM Lots of redundancy b/c PCM representation is a basic sine wave If representing the sine wave based on frequency rather than time, only need to store information regarding frequency, amplitude, and phase in order to represent the information Can reduce data without information loss Extends playing time, Allows for miniaturization and greater equipment tolerance, Reduces cost 2

3 Lossless vs. Lossy (Perceptive) Lossless coding allows perfect reconstruction of a signal (theoretically) Lossy Coding creates a more highly compressed signal, but some unnecessary frequencies are eliminated Perceptually, however, lossy coding results in no difference in how it SOUNDS to a person MP3s are lossy, but perceptually lossless MPEG Moving Picture Experts Group Aim to create standards relating to synchronized audio and video compression MPEG-1 MPEG-2 3

4 MPEG-1 Block Diagrams Topics Discussed in Detail After Diagrams Layers I and II Filter Bank (32 Sub-Bands) 31 Uniform Midtread Quanitzer Bitstream Formatting Coded Audio Data DFT 512/124 Hann Window Psychoacoustic Model Coding of Side Information 4

5 Layer III Filter Bank (32 Sub-Bands) 31 MDCT 511 Non-Uniform Midtread Quantizer Rate/Distortion Loop DFT 2 * 124 Hann Window Psychoacoustic Model Huffman Coding Coding of Side Information Bitstream Formatting Coded Audio Data Time to Frequency Mapping Filters parse signal to bands Quantized to a limited number of bits Noise put in bands barely audible Sent to decoder where sound is restored Input H y y G Output x x H y y G Encoder Decoder 5

6 Z Transform Assists in splitting frequencies Discrete Time generalization of the Fourier transform Important Properties Linearity Convolution Theorem Delay Theorem Can model all kinds of filter banks through it Representation of frequency content Layer III Filter Bank (32 Sub-Bands) 31 MDCT 511 Non-Uniform Midtread Quantizer Rate/Distortion Loop DFT 2 * 124 Hann Window Psychoacoustic Model Huffman Coding Coding of Side Information Bitstream Formatting Coded Audio Data 6

7 Time to Frequency Mapping Filters parse signal to bands Quantized to a limited number of bits Noise put in bands barely audible Sent to decoder where sound is restored Input H y y G Output x x H y y G Encoder Decoder MPEG Time to Frequency Mapping Analysis Filter: Synthesis Filter: 1 2 π 32 h k [ n] = h[ n] cos k + ( n + 16) 1 π [ n] = 32 h[ n] cos k + ( n + 16) k =,1,,31; n =,1,,511 Uses a filter of 32 bands, signal represented by 512 samples The above equations allow for taking apart the signal (the h part of the time to frequency mapping diagram) and putting it back together (the g part of the time to frequency mapping diagram) g k

8 Layer III Filter Bank (32 Sub-Bands) 31 MDCT 511 Non-Uniform Midtread Quantizer Rate/Distortion Loop DFT 2 * 124 Hann Window Psychoacoustic Model Huffman Coding Coding of Side Information Bitstream Formatting Coded Audio Data PQMF & MDCT Both are methods of time to frequency mapping Pseudo-Quadrature Mirror Function Multiple Discrete Cosine Transformation Mathematically, they are equivalent PQMF involves using Z transforms to represent the amplitudes of the frequency MDCT involves performing a block transform using a window to represent amplitudes These amplitudes are then quantized 8

9 Layer III Filter Bank (32 Sub-Bands) 31 MDCT 511 Non-Uniform Midtread Quantizer Rate/Distortion Loop DFT 2 * 124 Hann Window Psychoacoustic Model Huffman Coding Coding of Side Information Bitstream Formatting Coded Audio Data Pyschoacoustic Model determines masking threshold for each sub band Uses human auditory property of Auditory Masking 9

10 Non-uniform Quantizer Analog to digital Quantizer: Maps amplitude values into finite number of bits Non-uniform : changes sample size according to amplitude values parts of signal with lesser amplitude coded with greater accuracy increases signal to noise ratio (SNR) Layer III Filter Bank (32 Sub-Bands) 31 MDCT 511 Non-Uniform Midtread Quantizer Rate/Distortion Loop DFT 2 * 124 Hann Window Psychoacoustic Model Huffman Coding Coding of Side Information Bitstream Formatting Coded Audio Data 1

11 Huffman coding For better data compression, variable-length Huffman codes are used to encode the quantized samples. quantized MDCT coefficients (for long blocks) arranged in order from lowest to highest frequency whole range divided into 3 sections, each coded with a different set of Huffman tables Bitstream Formatting formats encoded quantized samples into an encoded bitstream final form in which the compressed signal is transmitted. 11

12 MPEG-4 and The Future? Incorporates speech and music compression More of an extension of MPEG-2 compression techniques with independent techniques geared specifically at coding for speech content (some coding for meaning) Hasn t really taken off yet, only time will tell MPEG-2 AAC (Advanced Audio Coding) is the audio format that is used if you download from the apple itunes store 12

Chapter 14. MPEG Audio Compression

Chapter 14. MPEG Audio Compression Chapter 14 MPEG Audio Compression 14.1 Psychoacoustics 14.2 MPEG Audio 14.3 Other Commercial Audio Codecs 14.4 The Future: MPEG-7 and MPEG-21 14.5 Further Exploration 1 Li & Drew c Prentice Hall 2003 14.1

More information

(Refer Slide Time: 2:08)

(Refer Slide Time: 2:08) Digital Voice and Picture Communication Prof. S. Sengupta Department of Electronics and Communication Engineering Indian Institute of Technology, Kharagpur Lecture - 30 AC - 3 Decoder In continuation with

More information

AUDIO CODING: BASICS AND STATE OF THE ART

AUDIO CODING: BASICS AND STATE OF THE ART AUDIO CODING: BASICS AND STATE OF THE ART PACS REFERENCE: 43.75.CD Brandenburg, Karlheinz Fraunhofer Institut Integrierte Schaltungen, Arbeitsgruppe Elektronische Medientechnolgie Am Helmholtzring 1 98603

More information

Multimedia Communications: Coding, Systems, and Networking. Prof. Tsuhan Chen MPEG Audio

Multimedia Communications: Coding, Systems, and Networking. Prof. Tsuhan Chen MPEG Audio 18-796 ultimedia Communications: Coding, Systems, and Networking Prof. Tsuhan Chen tsuhan@ece.cmu.edu PEG Audio 1 Outline Basics Psychoacoustics Subband coding PEG-1 audio Layer I and II Layer III Frame

More information

MP3 STIMULI IN ROOM ACOUSTICS

MP3 STIMULI IN ROOM ACOUSTICS 19 th INTERNATIONAL CONGRESS ON ACOUSTICS MADRID, 2-7 SEPTEMBER 2007 MP3 STIMULI IN ROOM ACOUSTICS PACS: 43.20.Ye Hak, C.C.J.M 1 ; Vertegaal, J.S. 2 1 Technische Universiteit Eindhoven, Department of Building

More information

Audio Coding, Psycho- Accoustic model and MP3

Audio Coding, Psycho- Accoustic model and MP3 INF5081: Multimedia Coding and Applications Audio Coding, Psycho- Accoustic model and MP3, NR Torbjørn Ekman, Ifi Nils Christophersen, Ifi Sverre Holm, Ifi What is Sound? Sound waves: 20Hz - 20kHz Speed:

More information

State of the Art in Perceptual Coding: MPEG-2/4 Advanced Audio Coding (AAC) Prof. Dr. Karlheinz Brandenburg,

State of the Art in Perceptual Coding: MPEG-2/4 Advanced Audio Coding (AAC) Prof. Dr. Karlheinz Brandenburg, State of the Art in Perceptual Coding: MPEG-2/4 Advanced Audio Coding (AAC) Prof. Dr. Karlheinz Brandenburg, bdg@idmt.fraunhofer.de Page 1 History 1994: Official start of AAC development Goal: Development

More information

STUDY OF MUTUAL INFORMATION IN PERCEPTUAL CODING WITH APPLICATION FOR LOW BIT-RATE COMPRESSION

STUDY OF MUTUAL INFORMATION IN PERCEPTUAL CODING WITH APPLICATION FOR LOW BIT-RATE COMPRESSION STUDY OF MUTUAL INFORMATION IN PERCEPTUAL CODING WITH APPLICATION FOR LOW BIT-RATE COMPRESSION Adiel Ben-Shalom, Michael Werman School of Computer Science Hebrew University Jerusalem, Israel. {chopin,werman}@cs.huji.ac.il

More information

Audio Watermarking in the Bitstream Domain

Audio Watermarking in the Bitstream Domain Audio ing in the Domain Jürgen Herre, Christian Neubauer Audio Department e for Integrated Circuits (FhG-IIS) Erlangen, Germany Dr. Jürgen Herre, hrr@iis.fhg.de Page 1 Overview Introduction Prerequisites

More information

Module 9 AUDIO CODING. Version 2 ECE IIT, Kharagpur

Module 9 AUDIO CODING. Version 2 ECE IIT, Kharagpur Module 9 AUDIO CODING Lesson 28 Basic of Audio Coding Instructional Objectives At the end of this lesson, the students should be able to : 1. Name at least three different audio signal classes. 2. Calculate

More information

Compression and Image Formats

Compression and Image Formats Compression Compression and Image Formats Reduce amount of data used to represent an image/video Bit rate and quality requirements Necessary to facilitate transmission and storage Required quality is application

More information

CM0340/CMT502 Solutions. Do not turn this page over until instructed to do so by the Senior Invigilator.

CM0340/CMT502 Solutions. Do not turn this page over until instructed to do so by the Senior Invigilator. CARDIFF UNIVERSITY EXAMINATION PAPER Academic Year: 2012/2013 Examination Period: Examination Paper Number: Examination Paper Title: Duration: Spring CM0340/CMT502 Solutions Multimedia 2 hours Do not turn

More information

For Articulation Purpose Only

For Articulation Purpose Only E305 Digital Audio and Video (4 Modular Credits) This document addresses the content related abilities, with reference to the module. Abilities of thinking, learning, problem solving, team work, communication,

More information

MPEG-1 / MPEG-2 BC Audio. Prof. Dr.-Ing. K. Brandenburg, bdg@idmt.fraunhofer.de Dr.-Ing. G. Schuller, shl@idmt.fraunhofer.de

MPEG-1 / MPEG-2 BC Audio. Prof. Dr.-Ing. K. Brandenburg, bdg@idmt.fraunhofer.de Dr.-Ing. G. Schuller, shl@idmt.fraunhofer.de MPEG-1 / MPEG-2 BC Audio The Basic Paradigm of T/F Domain Audio Coding Digital Audio Input Filter Bank Bit or Noise Allocation Quantized Samples Bitstream Formatting Encoded Bitstream Signal to Mask Ratio

More information

MPEG-1 / MPEG-2 BC Audio. Prof. Dr.-Ing. K. Brandenburg, Dr.-Ing. G. Schuller,

MPEG-1 / MPEG-2 BC Audio. Prof. Dr.-Ing. K. Brandenburg, Dr.-Ing. G. Schuller, MPEG-1 / MPEG-2 BC Audio Prof. Dr.-Ing. K. Brandenburg, bdg@idmt.fraunhofer.de Dr.-Ing. G. Schuller, shl@idmt.fraunhofer.de Page 1 The Basic Paradigm of T/F Domain Audio Coding Digital Audio Input Filter

More information

AUDIO SIGNAL PROCESSING AND CODING

AUDIO SIGNAL PROCESSING AND CODING AUDIO SIGNAL PROCESSING AND CODING A. Spanias, T. Painter, and V. Atti MP3 Decoder MP3 and Hi-Fi audio compression MP3 bit stream Perceptual audio coding, Psychoacoustics, Quantization, Bit-allocation,

More information

A Comparison of the ATRAC and MPEG-1 Layer 3 Audio Compression Algorithms Christopher Hoult, 18/11/2002 University of Southampton

A Comparison of the ATRAC and MPEG-1 Layer 3 Audio Compression Algorithms Christopher Hoult, 18/11/2002 University of Southampton A Comparison of the ATRAC and MPEG-1 Layer 3 Audio Compression Algorithms Christopher Hoult, 18/11/2002 University of Southampton Abstract This paper intends to give the reader some insight into the workings

More information

Fundamentals of Perceptual Audio Encoding

Fundamentals of Perceptual Audio Encoding Harvard-MIT Division of Health Sciences and Technology HST.723: Neural Coding and Perception of Sound Instructor: Bertrand Delgutte Fundamentals of Perceptual Audio Encoding Craig Lewiston HST.723 Lab

More information

Image Compression. Review

Image Compression. Review Image Compression Lossy Compression and JPEG Review Image Compression Image data too big in RAW pixel format Many redundancies We would like to reduce redundancies Three basic types Coding Redundancy Interpixel

More information

Dolby AC-3 and other audio coders

Dolby AC-3 and other audio coders Dolby AC-3 and other audio coders Prof. Dr. Karlheinz Brandenburg Fraunhofer IDMT & Ilmenau Technical University Ilmenau, Germany Prof. Dr.-Ing. Karlheinz Brandenburg, bdg@idmt.fraunhofer.de Page 1 Dolby

More information

CM0340 Solutions. Do not turn this page over until instructed to do so by the Senior Invigilator.

CM0340 Solutions. Do not turn this page over until instructed to do so by the Senior Invigilator. CARDIFF UNIVERSITY EXAMINATION PAPER Academic Year: 2009/2010 Examination Period: Examination Paper Number: Examination Paper Title: Duration: Autumn CM0340 Solutions Multimedia 2 hours Do not turn this

More information

Introduction and Comparison of Common Videoconferencing Audio Protocols I. Digital Audio Principles

Introduction and Comparison of Common Videoconferencing Audio Protocols I. Digital Audio Principles Introduction and Comparison of Common Videoconferencing Audio Protocols I. Digital Audio Principles Sound is an energy wave with frequency and amplitude. Frequency maps the axis of time, and amplitude

More information

AC-3 and DTS. Prof. Dr.-Ing. Gerald Schuller. Fraunhofer IDMT & Ilmenau University of Technology Ilmenau, Germany

AC-3 and DTS. Prof. Dr.-Ing. Gerald Schuller. Fraunhofer IDMT & Ilmenau University of Technology Ilmenau, Germany AC-3 and DTS Prof. Dr.-Ing. Gerald Schuller Fraunhofer IDMT & Ilmenau University of Technology Ilmenau, Germany Page 1 Dolby Digital Dolby Digital (AC-3) was first commercially used in 1992 Multi-channel

More information

Introduction to MPEG-1/2 L2 Audio 尤信程國立台北科技大學資訊工程系

Introduction to MPEG-1/2 L2 Audio 尤信程國立台北科技大學資訊工程系 Introduction to MPEG-1/2 L2 Audio 尤信程國立台北科技大學資訊工程系 Contents Intro to audio coding Psychoacoustics Audio encoding Frame structure Audio decoding Conclusions Intro to audio coding (1) Audio coding uses MPEG-1/2

More information

ISO/IEC 11172-4 INTERNATIONAL STANDARD

ISO/IEC 11172-4 INTERNATIONAL STANDARD INTERNATIONAL STANDARD ISO/IEC 11172-4 First edition 1995-03-I 5 Information technology - Coding of moving pictures and associated audio for digital storage media at up to about I,5 Mbit/s - Part 4: Compliance

More information

Computer Networks and Internets, 5e Chapter 6 Information Sources and Signals. Introduction

Computer Networks and Internets, 5e Chapter 6 Information Sources and Signals. Introduction Computer Networks and Internets, 5e Chapter 6 Information Sources and Signals Modified from the lecture slides of Lami Kaya (LKaya@ieee.org) for use CECS 474, Fall 2008. 2009 Pearson Education Inc., Upper

More information

4 Digital Video Signal According to ITU-BT.R.601 (CCIR 601) 43

4 Digital Video Signal According to ITU-BT.R.601 (CCIR 601) 43 Table of Contents 1 Introduction 1 2 Analog Television 7 3 The MPEG Data Stream 11 3.1 The Packetized Elementary Stream (PES) 13 3.2 The MPEG-2 Transport Stream Packet.. 17 3.3 Information for the Receiver

More information

Audio Coding Introduction

Audio Coding Introduction Audio Coding Introduction Lecture WS 2013/2014 Prof. Dr.-Ing. Karlheinz Brandenburg bdg@idmt.fraunhofer.de Prof. Dr.-Ing. Gerald Schuller shl@idmt.fraunhofer.de Page Nr. 1 Organisatorial Details - Overview

More information

A HIGH PERFORMANCE SOFTWARE IMPLEMENTATION OF MPEG AUDIO ENCODER. Figure 1. Basic structure of an encoder.

A HIGH PERFORMANCE SOFTWARE IMPLEMENTATION OF MPEG AUDIO ENCODER. Figure 1. Basic structure of an encoder. A HIGH PERFORMANCE SOFTWARE IMPLEMENTATION OF MPEG AUDIO ENCODER Manoj Kumar 1 Mohammad Zubair 1 1 IBM T.J. Watson Research Center, Yorktown Hgts, NY, USA ABSTRACT The MPEG/Audio is a standard for both

More information

Do not turn this page over until instructed to do so by the Senior Invigilator.

Do not turn this page over until instructed to do so by the Senior Invigilator. CARDIFF UNIVERSITY EXAMINATION PAPER SOLUTIONS Academic Year: 2002-2003 Examination Period: Autumn 2002 Examination Paper Number: CM0340 Examination Paper Title: Multimedia Duration: 2 hours Do not turn

More information

Overview of Digital Signal Processing (DSP)

Overview of Digital Signal Processing (DSP) Overview of Digital Signal Processing (DSP) Signal: Anything that conveys information, e.g., Speech Electrocardiogram (ECG) ( 心電圖 ) Radar pulse DNA sequence Stock price Code division multiple access (CDMA)

More information

The Theory Behind Mp3

The Theory Behind Mp3 The Theory Behind Mp3 Rassol Raissi December 2002 Abstract Since the MPEG-1 Layer III encoding technology is nowadays widely used it might be interesting to gain knowledge of how this powerful compression/decompression

More information

Analog Representations of Sound

Analog Representations of Sound Analog Representations of Sound Magnified phonograph grooves, viewed from above: The shape of the grooves encodes the continuously varying audio signal. Analog to Digital Recording Chain ADC Microphone

More information

Voice---is analog in character and moves in the form of waves. 3-important wave-characteristics:

Voice---is analog in character and moves in the form of waves. 3-important wave-characteristics: Voice Transmission --Basic Concepts-- Voice---is analog in character and moves in the form of waves. 3-important wave-characteristics: Amplitude Frequency Phase Voice Digitization in the POTS Traditional

More information

Quantization. Yao Wang Polytechnic University, Brooklyn, NY11201

Quantization. Yao Wang Polytechnic University, Brooklyn, NY11201 Quantization Yao Wang Polytechnic University, Brooklyn, NY11201 http://eeweb.poly.edu/~yao Outline Review the three process of A to D conversion Quantization Uniform Non-uniform Mu-law Demo on quantization

More information

H.263 Video Encoder. Introduction to topic

H.263 Video Encoder. Introduction to topic H.263 Video Encoder Introduction to topic Topic of the work A simplified H.263 video encoder on DE2 FPGA Education and Development board The exercise work consists of several phases and sub-tasks Receiving

More information

MP3 Player CSEE 4840 SPRING 2010 PROJECT DESIGN. zl2211@columbia.edu. ml3088@columbia.edu

MP3 Player CSEE 4840 SPRING 2010 PROJECT DESIGN. zl2211@columbia.edu. ml3088@columbia.edu MP3 Player CSEE 4840 SPRING 2010 PROJECT DESIGN Zheng Lai Zhao Liu Meng Li Quan Yuan zl2215@columbia.edu zl2211@columbia.edu ml3088@columbia.edu qy2123@columbia.edu I. Overview Architecture The purpose

More information

PCM Encoding and Decoding:

PCM Encoding and Decoding: PCM Encoding and Decoding: Aim: Introduction to PCM encoding and decoding. Introduction: PCM Encoding: The input to the PCM ENCODER module is an analog message. This must be constrained to a defined bandwidth

More information

Audio File Formats. - Formats with lossy compression, such as MP3, Vorbis, lossy Window Media Audio (WMA) and AAC.

Audio File Formats. - Formats with lossy compression, such as MP3, Vorbis, lossy Window Media Audio (WMA) and AAC. Audio File Formats An audio file format is a container format for storing audio data on a computer system. There are numerous file formats for storing audio data. The general approach towards storing digital

More information

Acoustics II: Kurt Heutschi sound storage media. vinyl records. analog tape recorder. compact disc. DVD Audio, Super Audio CD

Acoustics II: Kurt Heutschi sound storage media. vinyl records. analog tape recorder. compact disc. DVD Audio, Super Audio CD Acoustics II: sound storage Kurt Heutschi 2013-01-18 sound storage : introduction main building blocks of a sound storage device: concept: signal is stored as geometrical form on rotating disc basic idea:

More information

MPEG Unified Speech and Audio Coding Enabling Efficient Coding of both Speech and Music

MPEG Unified Speech and Audio Coding Enabling Efficient Coding of both Speech and Music ISO/IEC MPEG USAC Unified Speech and Audio Coding MPEG Unified Speech and Audio Coding Enabling Efficient Coding of both Speech and Music The standardization of MPEG USAC in ISO/IEC is now in its final

More information

Digital Transmission of Analog Data: PCM and Delta Modulation

Digital Transmission of Analog Data: PCM and Delta Modulation Digital Transmission of Analog Data: PCM and Delta Modulation Required reading: Garcia 3.3.2 and 3.3.3 CSE 323, Fall 200 Instructor: N. Vlajic Digital Transmission of Analog Data 2 Digitization process

More information

DIGITAL AUDIO WATERMARKING USING PSYCHOACOUSTIC MODEL

DIGITAL AUDIO WATERMARKING USING PSYCHOACOUSTIC MODEL DIGITAL AUDIO WATERMARKING USING PSYCHOACOUSTIC MODEL AND SPREAD SPECTRUM THEORY Manish Neoliya School of Electrical and Electronics Engineering Nanyang Technological University Singapore-639789 Email:

More information

2: Audio Basics. Audio Basics. Mark Handley

2: Audio Basics. Audio Basics. Mark Handley 2: Audio Basics Mark Handley Audio Basics Analog to Digital Conversion Sampling Quantization Aliasing effects Filtering Companding PCM encoding Digital to Analog Conversion 1 Analog Audio Sound Waves (compression

More information

MP3 AND AAC EXPLAINED

MP3 AND AAC EXPLAINED MP3 AND AAC EXPLAINED KARLHEINZ BRANDENBURG ½ ½ Fraunhofer Institute for Integrated Circuits FhG-IIS A, Erlangen, Germany bdg@iis.fhg.de The last years have shown widespread proliferation of.mp3-files,

More information

Image Compression through DCT and Huffman Coding Technique

Image Compression through DCT and Huffman Coding Technique International Journal of Current Engineering and Technology E-ISSN 2277 4106, P-ISSN 2347 5161 2015 INPRESSCO, All Rights Reserved Available at http://inpressco.com/category/ijcet Research Article Rahul

More information

Introduction to Digital Audio

Introduction to Digital Audio Introduction to Digital Audio Before the development of high-speed, low-cost digital computers and analog-to-digital conversion circuits, all recording and manipulation of sound was done using analog techniques.

More information

Introduction to image coding

Introduction to image coding Introduction to image coding Image coding aims at reducing amount of data required for image representation, storage or transmission. This is achieved by removing redundant data from an image, i.e. by

More information

JPEG Compression Reference: Chapter 6 of Steinmetz and Nahrstedt Motivations: 1. Uncompressed video and audio data are huge. In HDTV, the bit rate easily exceeds 1 Gbps. --> big problems for storage and

More information

Introduction to Medical Image Compression Using Wavelet Transform

Introduction to Medical Image Compression Using Wavelet Transform National Taiwan University Graduate Institute of Communication Engineering Time Frequency Analysis and Wavelet Transform Term Paper Introduction to Medical Image Compression Using Wavelet Transform 李 自

More information

Broadband Networks. Prof. Dr. Abhay Karandikar. Electrical Engineering Department. Indian Institute of Technology, Bombay. Lecture - 29.

Broadband Networks. Prof. Dr. Abhay Karandikar. Electrical Engineering Department. Indian Institute of Technology, Bombay. Lecture - 29. Broadband Networks Prof. Dr. Abhay Karandikar Electrical Engineering Department Indian Institute of Technology, Bombay Lecture - 29 Voice over IP So, today we will discuss about voice over IP and internet

More information

VOL. 2, NO. 4, May 2012 ISSN ARPN Journal of Science and Technology All rights reserved.

VOL. 2, NO. 4, May 2012 ISSN ARPN Journal of Science and Technology All rights reserved. Analysis of Various Image Compression Techniques 1 G.M.Padmaja, 2 P.Nirupama 1 Senior Assistant Professor in CSE Dept, BVRIT 2 Associate Professor in CSE Dept, SIET 1 padmaja.gmp@gmail.com, 2 nirupama.cse1@gmail.com

More information

10/3/11. Chapter 4: Sound. Overview. Introduction to Sound

10/3/11. Chapter 4: Sound. Overview. Introduction to Sound Chapter 4: Sound Overview Introduction to sound Digital audio MIDI audio MIDI versus digital audio Recording and editing digital audio Audio file formats Adding sound to multimedia projects Introduction

More information

MPEG USAC Minjie Xie Huawei Technologies

MPEG USAC Minjie Xie Huawei Technologies MPEG USAC Minjie Xie Huawei Technologies www.huawei.com HUAWEI TECHNOLOGIES CO., LTD. HUAWEI TECHNOLOGIES CO., LTD. Page 1 Overview of Main MPEG Audio Standards MPEG-1: standardized in 1992 MPEG-2: standardized

More information

A Secure File Transfer based on Discrete Wavelet Transformation and Audio Watermarking Techniques

A Secure File Transfer based on Discrete Wavelet Transformation and Audio Watermarking Techniques A Secure File Transfer based on Discrete Wavelet Transformation and Audio Watermarking Techniques Vineela Behara,Y Ramesh Department of Computer Science and Engineering Aditya institute of Technology and

More information

Digital Audio Compression

Digital Audio Compression By Davis Yen Pan Abstract Compared to most digital data types, with the exception of digital video, the data rates associated with uncompressed digital audio are substantial. Digital audio compression

More information

FIR Filter Design. FIR Filters and the z-domain. The z-domain model of a general FIR filter is shown in Figure 1. Figure 1

FIR Filter Design. FIR Filters and the z-domain. The z-domain model of a general FIR filter is shown in Figure 1. Figure 1 FIR Filters and the -Domain FIR Filter Design The -domain model of a general FIR filter is shown in Figure. Figure Each - box indicates a further delay of one sampling period. For example, the input to

More information

Speech Signal Processing: An Overview

Speech Signal Processing: An Overview Speech Signal Processing: An Overview S. R. M. Prasanna Department of Electronics and Electrical Engineering Indian Institute of Technology Guwahati December, 2012 Prasanna (EMST Lab, EEE, IITG) Speech

More information

Fundamentals Series Analog vs. Digital. Polycom, Inc. All rights reserved.

Fundamentals Series Analog vs. Digital. Polycom, Inc. All rights reserved. Fundamentals Series Analog vs. Digital Polycom, Inc. All rights reserved. Fundamentals Series Signals H.323 Analog vs. Digital SIP Defining Quality Standards Network Communication I Network Communication

More information

Relative Data Redundancy

Relative Data Redundancy Image Compression Relative Data Redundancy Let b and b denote the number of bits in two representations of the same information, the relative data redundancy R is R = 1-1/C C is called the compression

More information

Chapter 7: Pulse Modulation

Chapter 7: Pulse Modulation Pulse shaping (continued) For multichannel TDM case: T and B For finite-width sample pulses: X (ω) Q(ω) where is the Fourier transform of sample pulse (slides 5-7). Problem (Example 7.3.1): Twenty PAM

More information

Multimedia Communications

Multimedia Communications Multimedia Communications Dr. Ing. Audio Processing and Coding MMC Overview 1. Introduction 2. Fundamentals (Signal Processing, Information Theorie) 3. Speech Processing & Coding 4. Audio Processing &

More information

White Paper: An Overview of the Coherent Acoustics Coding System

White Paper: An Overview of the Coherent Acoustics Coding System White Paper: An Overview of the Coherent Acoustics Coding System Mike Smyth June 1999 Introduction Coherent Acoustics is a digital audio compression algorithm designed for both professional and consumer

More information

MPEG & H.26L OVERVIEW. Nuno Vasconcelos (with thanks to Truong Nguyen)

MPEG & H.26L OVERVIEW. Nuno Vasconcelos (with thanks to Truong Nguyen) MPEG & H.26L OVERVIEW Nuno Vasconcelos (with thanks to Truong Nguyen) Video Compression Codec Characteristics Temporal & Spatial Compression Codec Settings Compression Standards MPEG-7 Codec Characteristics

More information

Sampling Theorem Notes. Recall: That a time sampled signal is like taking a snap shot or picture of signal periodically.

Sampling Theorem Notes. Recall: That a time sampled signal is like taking a snap shot or picture of signal periodically. Sampling Theorem We will show that a band limited signal can be reconstructed exactly from its discrete time samples. Recall: That a time sampled signal is like taking a snap shot or picture of signal

More information

CCD. 500,000 to 10,000,000 Photosites

CCD. 500,000 to 10,000,000 Photosites Digital Video Video Starts off as Analog Information Just as in Imaging, the information contained in video is analog by nature Intensity Color Speed / Motion (24/30 Frames per Second) Digital Technology

More information

Do not turn this page over until instructed to do so by the Senior Invigilator.

Do not turn this page over until instructed to do so by the Senior Invigilator. CARDIFF UNIVERSITY EXAMINATION PAPER Academic Year: 2014/2015 Examination Period: Examination Paper Number: Examination Paper Title: Duration: Autumn CM3106 Solutions Multimedia Solutions 2 hours Do not

More information

encoding compression encryption

encoding compression encryption encoding compression encryption ASCII utf-8 utf-16 zip mpeg jpeg AES RSA diffie-hellman Expressing characters... ASCII and Unicode, conventions of how characters are expressed in bits. ASCII (7 bits) -

More information

Audio Coding Algorithm for One-Segment Broadcasting

Audio Coding Algorithm for One-Segment Broadcasting Audio Coding Algorithm for One-Segment Broadcasting V Masanao Suzuki V Yasuji Ota V Takashi Itoh (Manuscript received November 29, 2007) With the recent progress in coding technologies, a more efficient

More information

L 19 Electronic Sound- Analog and Digital

L 19 Electronic Sound- Analog and Digital L 19 Electronic Sound- Analog and Digital Electronics in Music 1.Intro 2.Basic Analog Electronics 3.Digital Audio Edison Phonograph - 1879 Cylindrical Phonogram (Thomas Edison 1877 ) (Youtube video) Acoustic

More information

Audio File Formats TYPES OF AUDIO FORMAT

Audio File Formats TYPES OF AUDIO FORMAT Audio File Formats TYPES OF AUDIO FORMAT Three major groups of audio file formats: Uncompressed audio formats, such as WAV, AIFF and AU; formats with lossless compression, such as FLAC, Monkey's Audio

More information

Signaling is the way data is communicated. This type of signal used can be either analog or digital

Signaling is the way data is communicated. This type of signal used can be either analog or digital 3.1 Analog vs. Digital Signaling is the way data is communicated. This type of signal used can be either analog or digital 1 3.1 Analog vs. Digital 2 WCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998

More information

Chapter 3 Discrete-Time Fourier Series. by the French mathematician Jean Baptiste Joseph Fourier in the early 1800 s. The

Chapter 3 Discrete-Time Fourier Series. by the French mathematician Jean Baptiste Joseph Fourier in the early 1800 s. The Chapter 3 Discrete-Time Fourier Series 3.1 Introduction The Fourier series and Fourier transforms are mathematical correlations between the time and frequency domains. They are the result of the heat-transfer

More information

Department of Electronics and Communication Engineering 1

Department of Electronics and Communication Engineering 1 DHANALAKSHMI COLLEGE OF ENGINEERING, CHENNAI DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING III Year ECE / V Semester EC 6502 PRINCIPLES OF DIGITAL SIGNAL PROCESSING QUESTION BANK Department of

More information

Real-Time Audio Watermarking Based on Characteristics of PCM in Digital Instrument

Real-Time Audio Watermarking Based on Characteristics of PCM in Digital Instrument Journal of Information Hiding and Multimedia Signal Processing 21 ISSN 273-4212 Ubiquitous International Volume 1, Number 2, April 21 Real-Time Audio Watermarking Based on Characteristics of PCM in Digital

More information

SGN-1158 Introduction to Signal Processing Test. Solutions

SGN-1158 Introduction to Signal Processing Test. Solutions SGN-1158 Introduction to Signal Processing Test. Solutions 1. Convolve the function ( ) with itself and show that the Fourier transform of the result is the square of the Fourier transform of ( ). (Hints:

More information

WILL THE REAL MAXIMUM SPL PLEASE STAND UP? Measured Maximum SPL vs Calculated Maximum SPL and how not to be fooled

WILL THE REAL MAXIMUM SPL PLEASE STAND UP? Measured Maximum SPL vs Calculated Maximum SPL and how not to be fooled Introduction When purchasing powered loudspeakers, most customers compare three key specifications: price, power and maximum SPL. Unfortunately, this can be like comparing apples and oranges. For the Maximum

More information

Data Storage 3.1. Foundations of Computer Science Cengage Learning

Data Storage 3.1. Foundations of Computer Science Cengage Learning 3 Data Storage 3.1 Foundations of Computer Science Cengage Learning Objectives After studying this chapter, the student should be able to: List five different data types used in a computer. Describe how

More information

MPEG-4 Lossless Coding for High-Definition Audio

MPEG-4 Lossless Coding for High-Definition Audio Audio Engineering Society Convention Paper Presented at the 115th Convention 2003 October 10 13 New York, NY, USA This convention paper has been reproduced from the author s advance manuscript, without

More information

Digital Audio Compression: Why, What, and How

Digital Audio Compression: Why, What, and How Digital Audio Compression: Why, What, and How An Absurdly Short Course Jeff Bier Berkeley Design Technology, Inc. 2000 BDTI 1 Outline Why Compress? What is Audio Compression? How Does it Work? Conclusions

More information

Improved N Level Decomposition-Hybrid DCT-DWT Image Compression

Improved N Level Decomposition-Hybrid DCT-DWT Image Compression International Journal of Engineering and Technical Research (IJETR) ISSN: 2321-0869, Volume-2, Issue-6, June 2014 Improved N Level Decomposition-Hybrid DCT-DWT Image Compression Sangeeta Abstract With

More information

MPEG Layer-3. An introduction to. 1. Introduction

MPEG Layer-3. An introduction to. 1. Introduction An introduction to MPEG Layer-3 MPEG Layer-3 K. Brandenburg and H. Popp Fraunhofer Institut für Integrierte Schaltungen (IIS) MPEG Layer-3, otherwise known as MP3, has generated a phenomenal interest among

More information

Reading.. IMAGE COMPRESSION- I IMAGE COMPRESSION. Image compression. Data Redundancy. Lossy vs Lossless Compression. Chapter 8.

Reading.. IMAGE COMPRESSION- I IMAGE COMPRESSION. Image compression. Data Redundancy. Lossy vs Lossless Compression. Chapter 8. Reading.. IMAGE COMPRESSION- I Week VIII Feb 25 Chapter 8 Sections 8.1, 8.2 8.3 (selected topics) 8.4 (Huffman, run-length, loss-less predictive) 8.5 (lossy predictive, transform coding basics) 8.6 Image

More information

Combined Compression/Watermarking for Audio Signals

Combined Compression/Watermarking for Audio Signals Combined Compression/Watermarking for Audio Signals Frank Siebenhaar, Christian Neubauer and Jürgen Herre Fraunhofer Institute for Integrated Circuits 91058 Erlangen, Germany ABSTRACT Perceptual audio

More information

(For Images) Why Use Data Compression? Types of Compression

(For Images) Why Use Data Compression? Types of Compression (For Images) Autumn 2016 CSCU9N5: Multimedia and HCI 1 Why Use Data Compression? Images in bitmap format take a lot of memory to store e.g. 1024 x 768 pixels x 24 bits-per-pixel = 2.4Mbytes 16 Mega pixel

More information

Further Lossless Compression of JPEG Images

Further Lossless Compression of JPEG Images Further Lossless Compression of JPEG Images Ingo Bauermann and Eckehard Steinbach Institute of Communication Networks, Technische Universität München, Munich, Germany {ingo.bauermann,eckehard.steinbach}@tum.de

More information

1.1) (15 pts.) Compute the DFT for the following two vectors with length N=4:

1.1) (15 pts.) Compute the DFT for the following two vectors with length N=4: Problem 1 (5 pts) 11) (15 pts) Compute the DFT for the following two vectors with length N=4: 1 1 1 x = 1, x 2 = 1 1 1 12) (15 pts) Compute the two-dimensional DFT with size M=N=4 for the following 4x4

More information

Quality Estimation for Scalable Video Codec. Presented by Ann Ukhanova (DTU Fotonik, Denmark) Kashaf Mazhar (KTH, Sweden)

Quality Estimation for Scalable Video Codec. Presented by Ann Ukhanova (DTU Fotonik, Denmark) Kashaf Mazhar (KTH, Sweden) Quality Estimation for Scalable Video Codec Presented by Ann Ukhanova (DTU Fotonik, Denmark) Kashaf Mazhar (KTH, Sweden) Purpose of scalable video coding Multiple video streams are needed for heterogeneous

More information

Lecture 2 Outline. EE 179, Lecture 2, Handout #3. Information representation. Communication system block diagrams. Analog versus digital systems

Lecture 2 Outline. EE 179, Lecture 2, Handout #3. Information representation. Communication system block diagrams. Analog versus digital systems Lecture 2 Outline EE 179, Lecture 2, Handout #3 Information representation Communication system block diagrams Analog versus digital systems Performance metrics Data rate limits Next lecture: signals and

More information

Department of Electrical and Computer Engineering Ben-Gurion University of the Negev. LAB 1 - Introduction to USRP

Department of Electrical and Computer Engineering Ben-Gurion University of the Negev. LAB 1 - Introduction to USRP Department of Electrical and Computer Engineering Ben-Gurion University of the Negev LAB 1 - Introduction to USRP - 1-1 Introduction In this lab you will use software reconfigurable RF hardware from National

More information

AUDIO CODING STANDARDS

AUDIO CODING STANDARDS AUDIO CODING STANDARDS Chi-Min Liu Department of Computer Science and Information Engineering National Chiao Tung University, Taiwan Wen-Whei Chang Department of Communication Engineering National Chiao

More information

Lecture 7: Audio compression and coding

Lecture 7: Audio compression and coding EE E682: Speech & Audio Processing & Recognition Lecture 7: Audio compression and coding Dan Ellis Michael Mandel Columbia University Dept. of Electrical Engineering

More information

ANALOG VS DIGITAL. Copyright 1998, Professor John T.Gorgone

ANALOG VS DIGITAL. Copyright 1998, Professor John T.Gorgone ANALOG VS DIGITAL 1 BASICS OF DATA COMMUNICATIONS Data Transport System Analog Data Digital Data The transport of data through a telecommunications network can be classified into two overall transport

More information

CHAPTER 5 CORONARY ANGIOGRAM VIDEO COMPRESSION USING WAVELET BASED CONTOURLET TRANSFORM AND REGION OF INTEREST TECHNIQUE

CHAPTER 5 CORONARY ANGIOGRAM VIDEO COMPRESSION USING WAVELET BASED CONTOURLET TRANSFORM AND REGION OF INTEREST TECHNIQUE 123 CHAPTER 5 CORONARY ANGIOGRAM VIDEO COMPRESSION USING WAVELET BASED CONTOURLET TRANSFORM AND REGION OF INTEREST TECHNIQUE 5.1 INTRODUCTION Coronary angiograms play an important role in the diagnosis

More information

Digital vs. Analog Transmission

Digital vs. Analog Transmission Digital vs. Analog Transmission Two forms of transmission: digital transmission: data transmission using square waves analog transmission: data transmission using all other waves Four possibilities to

More information

S Transmission Methods in Telecommunication Systems (4 cr)

S Transmission Methods in Telecommunication Systems (4 cr) S-72.245 Transmission Methods in Telecommunication Systems (4 cr) Sampling and Pulse Coded Modulation Sampling and Pulse Coded Modulation Pulse amplitude modulation Sampling Ideal sampling by impulses

More information

Image Compression Using Wavelet Methods

Image Compression Using Wavelet Methods Image Compression Using Wavelet Methods Yasir S. AL - MOUSAWY*,1, Safaa S. MAHDI 1 *Corresponding author *,1 Medical Eng. Dept., Al-Nahrain University, Baghdad, Iraq Yasir_bio@yahoo.com, dr_safaaisoud@yahoo.com

More information

Tutorial about the VQR (Voice Quality Restoration) technology

Tutorial about the VQR (Voice Quality Restoration) technology Tutorial about the VQR (Voice Quality Restoration) technology Ing Oscar Bonello, Solidyne Fellow Audio Engineering Society, USA INTRODUCTION Telephone communications are the most widespread form of transport

More information

Digital Data 9/22/13. Digital Data. Digital Data. Binary and Hexadecimal numbers. ASCII code and UNICODE. Sampling and Quantitizing

Digital Data 9/22/13. Digital Data. Digital Data. Binary and Hexadecimal numbers. ASCII code and UNICODE. Sampling and Quantitizing Digital Data Patrice Koehl Computer Science UC Davis Digital Data Binary and Hexadecimal numbers ASCII code and UNICODE Sampling and Quantitizing Example: sound Digital Data Binary and Hexadecimal numbers

More information

Image compression. Stefano Ferrari. Università degli Studi di Milano Elaborazione delle immagini (Image processing I)

Image compression. Stefano Ferrari. Università degli Studi di Milano Elaborazione delle immagini (Image processing I) Image compression Stefano Ferrari Università degli Studi di Milano stefano.ferrari@unimi.it Elaborazione delle immagini (Image processing I) academic year 2011 2012 Data and information The representation

More information