Play Opus audio

[stolen]

Is your feature request related to a problem? Please describe.

I want to play a video (fMP4 paylist) which has audio track encoded with Opus codec.
I need to specify that in CODECS parameter, but there is no way to make it work:

• opus is rejected by hls.js because sampleEntryCodesISO has key Opus but not opus
• Opus is rejected by Chrome and Firefox because these browsers violate specs

Lowercase opus works with some players (bitmovin, castr.io) while Opus does not.

Describe the solution you'd like

It seems to be less evil to accept lowercase opus codec as de-facto standard.

Additional context

Sample playlists + segments https://gist.github.com/stolen/c7f9ced139fb38b5759ff3a73d7a6717
PR with proposed solution #4526

[BlakeB415]

Note: Firefox now supports both "opus" and "Opus"
https://bugzilla.mozilla.org/show_bug.cgi?id=1778333

Here's the open issue for chromium.
https://bugs.chromium.org/p/chromium/issues/detail?id=1342217

In the meantime, wouldn't it be better to check for both "opus" and "Opus" when checking for support? Removing the spec accurate codec ID entirely is not a good idea.

Another thing to note is that bento4 outputs "Opus" as the codec.

[robwalch]

Thanks @BlakeB415,

Added back "Opus" to the list of audio codecs so that HLS.js recognizes it as an audio codec: b8d8e09

Browsers will still need to fix case sensitivity issues with SourceBuffer.isTypeSupported() (and canPlayType, and MediaCapabilities where needed). HLS.js will check for support using the codec string provided in the playlist.