[FFmpeg-devel] [PATCH] mov demuxer should individually index multi-framed audio chunks

Baptiste Coudurier baptiste.coudurier
Wed Mar 26 12:23:43 CET 2008

Hi Pascal,

Pascal Massimino wrote:
>   Hi,
>  i guess this one is for (flying?) Baptiste: when an MP4
>  file contains audio chunks with several frames, and we
>  lack the samples_per_frame information, we fail to
>  index each frames separately, breaking the demuxing.

Humm, amr decoding works fine.
I believe this could arise when aac exact cbr is present,
it would demux multiple aac frames in one packet.

>  The attached patch proposes to use the full-fledged
>  indexing loop in case samples_per_frame is lacking (==0)
>  Not sure it's the proper fix, though.

Problem here is that when samples_per_frame is not available (stsd v0),
this will cause splitting chunks per sample for uncompressed audio (!!!).

I was thinking about this to split amr chunks. One solution would be to
use mov->isom, though I know .mj2 can store uncompressed audio.

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