openairplay/airplay2-receiver

Question: what does extradata do?

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systemcrash commented

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

airplay2-receiver/ap2/connections/audio.py

Lines 217 to 222 in d28733e

extradata = bytes([
# Offset 0x00000000 to 0x00000035
0x00, 0x00, 0x00, 0x24, 0x61, 0x6c, 0x61, 0x63, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x01, 0x60, 0x00, 0x10, 0x28, 0x0a, 0x0e, 0x02, 0x00, 0xff,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xac, 0x44
])

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