The Recording Composition API allows developers to transcode, combine and mix Group Room Video Recording programmatically. These recordings are stored as separate audio and video tracks, but session playback has been complex due to the need to mix and synchronize the tracks.
Twilio created the Recording Composition API to solve this. Developers pass the API various parameters, including the sources, video layout, and resolution, and the API produces a composition that is stored in the Twilio Cloud and made available for download.
The cost of creating a recording composition is $0.01 per composition minute. Storage is free for the first 30 days, after which time developers pay $0.05 per stored GB per month and $0.1 per downloaded GB. In the near future, Twilio plans to add additional features, such as support for FullHD compositions.