[MPlayer-dev-eng] [PATCH] Add "lpcJ" fourcc to codecs.conf

Francesco Lavra francescolavra at interfree.it
Fri May 28 21:12:18 CEST 2010


On Fri, 2010-05-07 at 20:47 +0200, Francesco Lavra wrote:
> On Sun, 2010-05-02 at 15:34 -0400, compn wrote:
> > On Sun, 02 May 2010 16:33:39 +0200, Francesco Lavra wrote:
> > >On Sun, 2010-05-02 at 14:08 +0000, Carl Eugen Hoyos wrote:
> > >> Francesco Lavra <francescolavra <at> interfree.it> writes:
> > >> 
> > >> > $subj, "lpcJ" is a valid fourcc for the RealAudio 1.0 codec.
> > >> 
> > >> Please point us to a sample and I will apply.
> > >
> > >If/when the just submitted patch series for the FFmpeg RM muxer will be
> > >applied, samples can be created with FFmpeg.
> > >If I have to wait until then, well, I don't mind :)
> > 
> > does realplayer handle those 1pcJ files ? is there a difference in the
> > codec/bitstream in 14_4 vs 1pcJ ? if not, why not just keep 14_4 and
> > abandon 1pcJ (in the encoder patch) ?
> > 
> > this codecs.conf entry seems fine to me as long as 1pcJ is an actual
> > fourcc found in the wild.
> 
> Realplayer plays those lpcJ files flawlessly.
> There is no difference in the bitstream between between 14_4 and lpcJ.
> But it would make more sense to drop the 14_4 tag in favor of lpcJ,
> since all samples that I found in the wild (including those in
> mplayerhq.hu) have lpcJ tag, not 14_4.
> The reason why the samples play with the unpatched mplayer is that the
> realmedia demuxer does not read the fourcc contained in the samples, and
> mplayer fills the codec_tag field based on its own tag lists.
> With the changes to the realmedia muxer that I'm proposing on the ffmpeg
> list, the format of the created samples is different in that it contains
> additional headers, from which the demuxer is able to get the codec tag;
> if the codec tag is obtained from the demuxer, mplayer doesn't use its
> own tag lists, and that causes it to fail.

Ping?
Now FFmpeg can create realmedia files that MPlayer cannot play.
In my previous mail I wasn't suggesting to drop the 14_4 tag, I just
meant that if you wanted only one tag for realaudio 14.4k, then lpcJ is
better than 14_4.





More information about the MPlayer-dev-eng mailing list