[FFmpeg-devel] Gain control not yet implemented

Pascal Massimino pascal.massimino
Tue Dec 4 17:49:25 CET 2007


On Dec 4, 2007 8:27 AM, Pascal Massimino <pascal.massimino at gmail.com> wrote:

>
>
> On Nov 29, 2007 10:16 AM, Gabriel Teixeira <gabrieldiegoteixeira at gmail.com>
> wrote:
>
> > Hi,
> >
> > I developed a application that uses the libavcodec, but only after
> > some months of development and testing appeared a weird message that I
> > never got before:
> > [mpeg4aac @ 01290000]faac: frame decoding failed: Gain control not yet
> > implemented
> > Since the audio was encoded with ffmpeg, I believed this frame
> > wouldn't have gain control or any stuff that ffmpeg could not decode.
> > This audio stream was sent over the web via multicast, so may be a
> > fail in the information transported. Anyway, how to identify and
> > correct this problem?
> >
>
>   this is a bug in FAAC: scale factor differences must be in range [-60,
> 59],
>  but faac can generate such big differences, and then writes
>  invalid huffman codes (cf huffman.c, WriteScalefactors()).
>  So you end up with invalid bitstreams.
>  This bug has been reported a long ago, a patch proposed, but wasn't
>  committed in cvs. Now, even the web page disappeared, so i can't
>  even find back the patch. I'll see if i can resurrect something on my
>  attic...
>

  here you go:

http://sourceforge.net/tracker/index.php?func=detail&aid=1638362&group_id=704&atid=100704

  i don't know why it didn't make to cvs, since bug reports for this
(cryptic) bug
  are to be found everywhere, under various flavors.
  Now, i'm not sure the proposed patch is 100% correct, though.

skal


>
> skal
>
>
> > Thanks in advance
> > Gabriel
> > _______________________________________________
> > ffmpeg-devel mailing list
> > ffmpeg-devel at mplayerhq.hu
> > http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel
> >
>
>




More information about the ffmpeg-devel mailing list