[FFmpeg-devel] [PATCH] avformat/mpegtsenc: add flag to embed an AC-3/E-AC-3 ES the DVB way

Stefan Pöschel basic.master at gmx.de
Thu Dec 17 23:08:10 CET 2015


Am 13.12.2015 um 15:23 schrieb Stefan Pöschel:
> Am 13.12.2015 um 14:18 schrieb Moritz Barsnick:
>> On Sun, Dec 13, 2015 at 11:54:32 +0100, Stefan Pöschel wrote:
>>> So far an AC-3 elementary stream is refered to in the PMT according to
>>> System A (ATSC). An E-AC-3 ES in contrast is embedded the System B (DVB) way.
>> Interesting, that's apparently the reason why my (DVB-)PVR didn't ever
>> recognize AC-3 in MPEG-TS. See
>> https://ffmpeg.org/pipermail/ffmpeg-user/2015-October/028812.html
>> E-AC-3 in MPEG-TS seems to have worked (I just tried it - successfully
>> - for the first time), I didn't realize that.
>> With your patch, I can now successfully play AC-3 and E-AC-3 with that
>> player, when using the "-mpegts_flags system_b" (and kill this
>> capability when not using it).
> I've had the same problem which was the motivation to take a look into it.
>>> To fix this inconsistency, this commit changes the default E-AC-3 behaviour to
>>> use the ATSC way, too. Furthermore a new flag is added to optionally select the
>>> DVB way (regarding both codecs and possible further differences in the future).
>> I never found the patch mentioned in the thread, and don't know enough
>> about the differences myself.
> There is a bug report of libav regarding this problem, together with a
> patch from 2011 which just changes the AC-3 signalling from ATSC to DVB:
> https://bugzilla.libav.org/show_bug.cgi?id=73
> Yesterday I therefore posted a patch to libav-devel (similar to this one
> for FFmpeg-devel) for switching between ATSC and DVB:
> https://lists.libav.org/pipermail/libav-devel/2015-December/073574.html
> Regards,
> 	Stefan
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel

More information about the ffmpeg-devel mailing list