By Alison Myers
This is a quick guide to the media needed by captioning and audio description companies. There seems to be increasing confusion around this, which is causing all kinds of avoidable mistakes. These days, productions often have different versions for different distributors, which seems to be complicating matters. So I thought I should try to clear things up.
Caption and audio description (AD) providers need the final version/s that will be released with captions and AD. Captioners need an mp4 or mov at a decent resolution. ADers also need a matching wav of the full mix. You don’t need to create special versions – just export the versions that need captions and AD.
Caption and AD files match the media that is used to create them. Captions and AD are timed to the frame. Our files will match the media provided to the frame. So if this media doesn’t match the media used for the production’s release, then the caption and AD files also won’t match. Common differences include countdowns, slates, cards, logos, commercial breaks, and black/silence. These are most disruptive at the start of the media, but can also cause problems at the end. The framerate and the BITC also need to match. So, if you are creating different versions for different distributors, then the captioners and ADers will need copies of all the relevant versions. If your film is in reels for cinema release, then we need the media in reels. If one streamer requires a countdown and 30 seconds of black, then the media needs to have the countdown and 30 seconds of black. If a streamer requires commercial breaks, then the media needs to have the commercial breaks.
AD and captions also match the content. So any last-minute re-edits or tweaks in sound and vision will likely require changes in captions and AD. Eg, if you add or change credits, the positioning and timing of captions might need to be adjusted, and the AD might need to be redone. If you tweak the timing of audio, then the captions and AD might need to be retimed or redone to match. So if any changes happen after the captioning and AD has started, please let your captioners and ADers know ASAP. And please provide as much detail as possible – it will save everyone time if the captioners and ADers don’t have to go through the entire production looking for changes.
Captioning and AD software is set up to exactly match the media provided. It’s also set up to adjust files to match different versions. We can absolutely make simple adjustments, eg adding 10 seconds at the start, without receiving different media, however this is MUCH easier if the original media is correct.
Media required – basics:
- Mp4 or mov of the release version/s at a decent resolution, eg credits and other onscreen text are legible but the file won’t take ages to transfer via internet.
- With BITC (burnt-in timecode),
- With mixed stereo audio – not L & R audio. We have found out the hard way that captioning and AD software only works with stereo mixes. If the audio is L & R, the software will only play one track which means we might not hear everything. - For AD we ALSO need:
- Wav/s of the FULL mix of the release version/s at release quality. (NOT the M&E mix.)
- Stereo wavs if you need stereo, 5.1 wavs if you need 5.1.Examples:
A feature is released in 24fps reels for cinema, 25fps continuous for Australian streamer, and 23.98fps with commercial breaks for US streamer. This is the media the captioner and AD provider will need.
- For cinema/DCP:
- 24fps video for each of the 5 reels, with BITC and stereo audio.
- No wav files are needed. (Cinema AD is mono wavs with just the timed AD.)- For 25fps continuous:
- 25fps video, with BITC and stereo audio.
- Wav file of the FULL mix in stereo or 5.1 as required. The wav file syncs with the 25fps video.- For 23.98fps with commercial breaks:
- 23.98fps video, with BITC and stereo audio, and with commercial breaks.
- Wav file of the FULL mix in stereo or 5.1 as required. The wav syncs with the 23.98fps video.So that means the captioners and ADers need seven videos and two wav files. These videos and wavs will also need to include any countdowns, slates, black/silence, etc. Again, you don’t need to create special versions – just export the versions that need captions and AD.
This is a very basic rundown. Talk with your captioning and AD providers about your requirements. When timing is tight, caption and AD providers can start work on unfinished productions, eg, using picture lock media but will need the final finished versions to create the final files. Captions and AD are created between a production’s completion and release when there is usually not a lot of time but changes are sometimes necessary. It is much quicker and easier to manage last-minute changes if the captioners and ADers have the correct media to work from.