RC wrote:
I've found an Apple h.264/AAC trailer that doesn't have any sound. I don't know if the problem lies with mplayer or with faad, but I figure somebody here will be able to tell for sure.
Looks like MPlayer is to blame. That audio stream is 7.1 channels, which mplayer apparently can't handle.
Ah, that's it. Thanks. I remember seeing several places in mplayer audio code that assume a maximum of 6 channels; up to now I'd never seen more in the wild. Maybe I'll be able to fix mplayer to handle more, though, at this point, I don't know what the proper fix is. It would be nice to handle an arbitrary number.
With -dumpaudio, I can output an AAC file that faad is happy to decode to a wav. I haven't yet been able to play anything back, as none of the programs I use will even downmix 8 channel wav files.
When I use faad on the dumpstream it downmixes to 6 channels, which I can then downmix to 2 with: mplayer stream.wav -af pan=2:1:0:0:1:1:0:0:1:0.5:0.5:1:1 Or, 'faad -d' downmixes to 2 channels. The audio by itself sounds fine to me. Out of curiosity, how were you able to determine that the audio track has 8 channels? Thanks, Corey