On Tue, 2008-09-30 at 00:51 -0700, Mike wrote: > I think there is some kind of regression with libavformat OR the way DVBCUT > uses it in the recent versions of ffmpeg SVN. This is in regards to > exporting MPEG2-TS to MPEG2-PS after editing with DVBCUT and exporting using > the "MPEG program stream/DVD (libavformat)" output. I'm currently using > DVBCUT SVN 123. The steps to reproduce the problem are as follows: > > 1) Compile and install a fresh checkout of ffmpeg > 2) Open a MPEG2-TS file in DVBCUT > 3) Make edits > 4) Export as "MPEG program stream/DVD (libavformat)" > 5) Process resulting MPEG2-PS using dvdauthor to a DVD > 6) Play DVD in consumer grade 480i DVD player connected to television. > DVD will have lots of skipping, freezing, and audio problems, completely > unwatchable. > > Now, redo the steps above except use "MPEG program stream/DVD (DVBCUT > multiplexer)" in step 4. Resulting DVD will play without any problem in the > DVD player. > > Now, redo the above again, except compile and install SVN version 13060 of > ffmpeg first, and use "MPEG program stream/DVD (libavformat)" as the export > type. The resulting DVD will have no problems in the DVD player. > > Summary: I was using ffmpeg 13060 for a long time with DVBCUT 123 and had no > problems exporting as "MPEG program stream/DVD (libavformat)". The next > version of ffmpeg that I installed was 14873 and I can confirm at least > somewhere inbetween those 2 versions something changed which prevents me from > exporting without problems as "MPEG program stream/DVD (libavformat)". > > I'm not sure if this is an ffmpeg problem or not, but I figured the DVBCUT > devs would be best to start with. Thanks. >
This is strange, as I have observed the exact opposite behaviour (with MPEG-PS from an ivtv card, making either PAL norm DVDs or simple MPEG files): with some grabs I had lots of skips and audio problems with the internal muxer, replex reported several PTS discontinuities. Using a fairly recent FFmpeg SVN build and the lavf muxer made the resulting file much more conformant (no audio problems and only a very few PTS discontinuities for an one-and-half hour long movie. BTW how did you manage to link against really recent FFmpeg libraries? The latest (SVN 131) version of DVBCut does not compile with these libraries: I had to modify avframe.cpp (instead of img_copy(), avcodec.h has now av_picture_copy()) and also lavfmuxer.cpp (where avcodec_decode_audio() became avcodec_decode_audio2()). With these changes, I can compile dvbcut, but when trying to use lavf as muxer the program complains about an aspect ratio mismatch between the encoder and the muxer and gets a floating point exception. A few days ago FFmpeg itself had also an aspect ratio bug preventing its use even from a pipe until Wolfram Gloger made a fix to ffmpeg.c. Unfortunately, I don't know what else should be changed for DVBcut, I know only a little bit of C(++), not enough to find where the source needs to be patched. Levente PS: BTW you used FFmpeg SVN-14873. The most recent is 15480! ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ DVBCUT-user mailing list DVBCUT-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dvbcut-user
