VP9 on Android Exoplayer transcoding

[TheDreadPirate]

Code:

{ Container: "webm", AudioCodec: "vorbis,opus", VideoCodec: "vp8,vp9,av1"
{ Container: "mkv", AudioCodec: ....VideoCodec: "h263,mpeg4,h264,hevc,av1,vp8,vp9,av1"

Your VP9 video is in MP4, which is not in the compatibility list. From what I can find, MP4 never officially added VP9 support. Something about a draft proposal from Netflix, but nothing about it being ratified.

If you remuxed your video into MKV, it would probably direct play. As for why JF doesn't do that for you, Jellyfin currently only transcodes to the TS container. I can't find clear documentation TS supports VP9, which is probably the reason it is transcoded instead.