[mythtv-users] ATSC Encoder change breaks Mythtv

[Taylor Ralph]

Greg,

On Fri, Oct 8, 2010 at 7:30 PM, Greg Maus <g.maus at fnmmail.com> wrote:
> Taylor,
>
> On Fri, 2010-10-08 at 14:30 -0400, Taylor Ralph wrote:
>> Greg,
>>
>> On Fri, Oct 8, 2010 at 6:28 AM, Greg Maus <g.maus at fnmmail.com> wrote:
>> > On Thu, 2010-10-07 at 21:06 -0400, Taylor Ralph wrote:
>> >> On Thu, Oct 7, 2010 at 7:41 PM, Greg Maus <g.maus at fnmmail.com> wrote:
>> >> >
>> >> >> Have you tried playing back the video files in another player
>> >> >> (MPlayer,
>> >> >> VLC, etc). What format is the audio stream in (MPlayer will tell
>> >> >> you)?
>> >> >> What is your audio output configuration? That information will
>> >> >> certainly
>> >> >> help.
>> >> >
>> >> > The recorded files that will not play in Myth frontend play fine in all
>> >> > of the common media players.  I am not exactly sure what you mean what
>> >> > format is the audio stream.  I know that it is AC3, and that is the same
>> >> > audio format as files that were recorded prior to the encoder change.
>> >> > Is there a command line option in mplayer to get more specific audio
>> >> > stream info?
>> >> >
>> >> > My Mythtv audio config is pretty basic.  ASLA:default.  I have also
>> >> > tried ALSA:spdif, but there is no difference in playback regardless of
>> >> > the settings.
>> >> >
>> >>
>> >> You need to provide a small sample so a dev can take a look at what's going on.
>> >>
>> >> Regards.
>> >> --
>> >> Taylor
>> >> _______________________________________________
>> >> mythtv-users mailing list
>> >> mythtv-users at mythtv.org
>> >> http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
>> >
>> > A sample file has been uploaded here:
>> > http://filebin.ca/mhvyt/KSTP_5.1sample.mpg
>> > Thank you!
>> >
>>
>> I've analyzed this video and unfortunately the FFmpeg mpegts demuxer
>> doesn't provide any valid video timestamps (DTS or PTS). Obviously,
>> this makes A-V sync impossible to accomplish. In mplayer the video
>> plays fine with perfect A-V sync but by default it doesn't use the
>> FFmpeg mpegts demuxer. So it is most likely a valid video format.
>> FFmpeg prints the following error when processing the video:
>>
>> [mpegts @ 0x93da2c0]invalid dts/pts combination
>>
>> The only way to get this resolved is to file a bug report at
>> http://ffmpeg.org/bugreports.html and provide the sample which you've
>> already created. Then open a ticket at
>> http://svn.mythtv.org/trac/newticket and reference the FFmpeg ticket.
>> Sorry I don't have better news but the sooner we get this fixed the
>> better since I can only imagine other broadcasters will start using
>> this new encoder at some point.
>>
>> Regards.
>>
>> --
>> Taylor
>> _______________________________________________
>> mythtv-users mailing list
>> mythtv-users at mythtv.org
>> http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
>
> I have opened tickets:
> FFmpeg Issue2286
> Mythtv #9076
>
> I mentioned your name as helping me to find the problems in the file.  I
> hope this is okay.
>
> Thank you,
> Greg
>

Thanks for providing the sample and bug reports.

This should now be fixed in trunk and 0.23-fixes.

Baptiste is correct that the file is technically broken but their
solution is a bit extreme for a player since it has to have a valid
video timestamp for A-V sync purposes. You might want to forward the
information in the roundup ticket to your broadcaster so they can
report the issue to the maker of the encoder.

Regards.

--
Taylor