YouTube makes videos available in a bewildering range of formats and codecs, from the cutting-edge to some old “legacy” formats that are still in common use. As new codecs become popular, it goes back and re-encodes existing videos to reduce its own bandwidth costs--this on top of the transcoding required for every new upload. It has decided that this never-ending transcoding burden now requires special-purpose hardware, and has published a paper on the subject. <https://arstechnica.com/gadgets/2021/04/youtube-is-now-building-its-own-video-transcoding-chips/>