SUBTITLING AND CLOSED CAPTION MANAGEMENT

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1 SUBTITLING AND CLOSED CAPTION MANAGEMENT Corporate North & Latin America Asia & Pacific Other regional offices Headquarters Headquarters Headquarters Available at

2 SUBTITLING AND CLOSED CAPTION MANAGEMENT... 4 THE WINDING PATH OF A SUBTITLE FILE... 5 TALKING ABOUT FILE CONVERSION... 6 THE FINISHED ARTICLE... 6

3 LEGAL INFO 2013 EVS Broadcast Equipment, all rights reserved. No part of this documentation or publication may be reproduced, transcribed, stored in a retrieval system, translated into any language, computer language, or transmitted in any form or by any means, electronically, mechanically, magnetically, optically, chemically, photocopied, manually, or otherwise, without prior written permission from EVS Broadcast Equipment. DISCLAIMER The information in this document is believed to be correct as of the date of publication. However, our policy is one of continual development so the information in this guide is subject to change without notice, and does not represent a commitment on the part of EVS Broadcast Equipment. TECHNICAL SUPPORT For the latest news, upgrades, documentation, and products, please visit the EVS website at LAST UPDATED

4 SUBTITLING AND CLOSED CAPTION MANAGEMENT Legislation from the EU and FCC requiring television programs to include closed captions and subtitling, combined with the growing need for multi-region distribution means that closed captioning and subtitling are now a key element of the content delivery process. Ideally, this is something that broadcasters have to ensure is done right from the moment content is ingested - however, in today s complex multi-channel, multi-format production environments, this is sometimes easier said than done. Throughout its lifecycle within a file-based workflow, subtitling has to be considered whether it s where to put the subtitle or what process it needs to go through (editing, etc). The format an AV file is in (SD or HD), as well as the type of encoder that was used to generate that file, will also impact the level of complexity involved in processing it. When the content is in SD format, subtitles are usually transported in VBI inactive lines, whereas in HD, they are carried in the ANC data, requiring different processing. In the production environment, subtitles are transported within the baseband SDI signal to the ancillary essence layer. They are then reconciled with the rest of the AV content at the playout stage. In the case of tape-to-file archive migration, the decision of whether to leave the subtitle within the video signal needs to be addressed, along with the question of how practical this is in the long-term due to the associated dependence on the codec technology. When the AV content is ingested, there are two options when it comes to the subtitling element of the file. Either the subtitles remains a raw VANC that is then wrapped in an MXF S436M track before it can progress further through the workflow, or they become a separate text file (eg, *.SCC or *.MCC). The MXF file wrapper has only recently been put forward as a viable option for handling timed text but at the moment this is not widely adopted except in the context of DCP workflows. EVS OpenCubeHD/SD can handle many of these options for subtitling and closed caption management at the ingest stage. Users can choose to keep ANC data along with subtitles and closed caption in the MXF file as a S436M track, or alternatively, a *.SCC or *.MCC sidecar file is generated alongside the MXF AV file and follows it through the production process.

5 THE WINDING PATH OF A SUBTITLE FILE Once an AV file is ingested into the workflow, it becomes increasingly easy to lose track of the subtitling element of that file. If you ve assigned the subtitles to remain as a raw VANC file, which is then wrapped in an MXF S436M track, it can be difficult to locate. You have to first identify whether a file has a S436M track and then look to see whether it carries subtitles. If it does so, what format are they in? How should they be displayed and how do you then check the subtitles to ensure they are correct and in sync? If you ve chosen to turn your subtitle into a text file (like *.SCC or *.MCC), it will follow a different path through the production workflow to one that is wrapped in an MXF S436M track. Sometimes, the workflow involves MOV files rather than MXF, in this case, a sidecar text file hitched to your main AV content, that follows it through the various steps in the production process, really makes a lot of sense. While the AV and subtitling get re-united prior to playout, it s essential that it s checked to make sure that any subtitling/closed captions are synchronised with the MXF video and audio. Once a file has been ingested using one of the two options above at each step along the workflow, users will need to check that the subtitle or closed caption information is synchronised with its associated video, or burned into the correct frame, as required. EVS XFReader provides a straightforward and efficient way to do this. Using EVS XFReader, the subtitle or closed caption can be decoded from the S436M track or from a side text file and burned in to the relevant frame. The metadata display clearly shows which channel is active within the 608, 708 or OP-47 data stream, allowing users to have a clear view of all the relevant components within a content file. Fig. 1: The latest version of XFReader enabled with closed caption management When EVS XFReader is enhanced with SDI capabilities, the closed caption data from *.SCC or *.MCC files is reinserted in the form of VANC data at the point when the MXF file is played back over baseband.

6 TALKING ABOUT FILE CONVERSION Regardless of what format a subtitling file takes and whatever its path through the production or archiving workflow, one thing is certain; it will need to be converted at several points along the way. This will usually be from a subtitling text file to one wrapped in an MXF S436M track and then unwrapped again at the other end of the production chain. This wrapping/un-wrapping process can be time consuming and inefficient, however EVS XFConverter addresses this issue. XFConverter enables users to bridge the gap between an MXF 436M VANC track and *.SCC files, reliably and automatically at each step of your workflow. Within a file-based workflow subtitling and closed captioning data is as crucial to the final output as audio and video. It s key to maintain the integrity of audio and video throughout the production process, and the same holds true for subtitling and closed captioning. Managing the smooth transport of this element of your content and checking it regularly to ensure there s no loss of integrity is vital at each stage. THE FINISHED ARTICLE When it comes to outputting the finished content whether that s to a playout server, to smart devices, or as an online streaming, VoD or DTT service the accurate management of your subtitles and closed captioning data, along with your MXF production file, makes the whole process a lot less complicated. Mastering your workflow hinges on being able to properly handle any subtitling and closed captioning data. Fig. 2: EVS Media s comprehensive workflow for subtitling and closed caption management EVS Media provides a comprehensive solution to manage closed captions and subtitles throughout the filed-based workflow. EVS solutions such as XFReader SDI and OpenCubeHD ensure that the entire subtitle management process has been fully integrated in to the workflow design rather than becoming a somewhat cumbersome and complex afterthought.

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