openairplay / airplay2-receiver

AirPlay 2 Receiver - Python implementation
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Question: what does extradata do? #9

Closed systemcrash closed 3 years ago

systemcrash commented 3 years ago

When selecting ALAC, does this extradata that goes to ffmpeg 'prime the pump' so to speak? Some ALAC header which determines incoming stream formatting?

https://github.com/openairplay/airplay2-receiver/blob/d28733ec60e624925d1f0a081c0e838a083d8b68/ap2/connections/audio.py#L217-L222

It's undocumented in PyAu. I suspected it was something to do with this

systemcrash commented 3 years ago

https://github.com/FFmpeg/FFmpeg/blob/b593abda6c642cb0c3959752dd235c2faf66837f/libavcodec/alac.c#L22-L46 ?