[Ffmpeg-devel] [BUG] libavformat mp3 in mp4 with fourcc mp4a

[Guillaume POIRIER]

Hi,

On 11/29/05, compn <tempn at twmi.rr.com> wrote:
> hello, while checking a sample in mplayer, i came across a libavformat problem
> libavformat detects 'mp4a' fourcc in mp4 as aac always, but mplayer detects
> mp4a as mp3 and/or aac when appropriate.
>
> you can check the sample at http://home.twmi.rr.com/compn/163.mp4
> its 3mb. i have 11mb of the file, or 'the wanderer' has a complete sample.
> these encodes are made by the kaizoku-fansubs group...
>
> the audio plays correctly using mplayer 163.mp4 -demuxer 35 -ac +ffmp3
>
> some mplayer output, the only thing different between an mp4a aac and mp4a mp3
> was the elementary stream descriptor atom...
>
> > AAC:
> > MOV track #0: 105 chunks, 948 samples
> > Audio bits: 16  chans: 2  rate: 44100
> > MOV: Found MPEG4 audio Elementary Stream Descriptor atom (51)!
> > Fourcc: mp4a
> >
> > MP3:
> > MOV track #1: 2886 chunks, 0 samples
> > Audio bits: 16  chans: 2  rate: 48000
> > MOV: Found MPEG4 audio Elementary Stream Descriptor atom (35)!
> > Fourcc: mp4a
>
> verified ffplay detects aac audio. is there a way to force codecs with ffplay?

I just tried with current cvs, the problem is still there it seems.

Guillaume

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