Extract audio from your videos with Cloudflare Stream

This post introduces audio extraction capabilities for Cloudflare Stream. It extends the existing Media Transformations service to extract audio-only M4A tracks on-the-fly by adding a `mode=audio` parameter to transformation URLs. It also adds audio-only download functionality to the Video-on-Demand (VOD) pipeline, with new API endpoints and asynchronous job processing for creating M4A files. The implementation involved extending validation logic in the OTFE pipeline to check for audio tracks and building a new transformation handler to discard visual tracks. For the VOD pipeline, new type-specific API endpoints were introduced, and the asynchronous queue consumer was updated to handle audio download types and use ffmpeg templates for M4A encoding.