Whatever problem I was having with nuvexport now seems to be resolved, so I can now create a cutlist in mythfrontend, fire up nuvexport, and get an edited MPEG-2 PS (I have a couple of MPEG encoders installed) out.
The PVRx50 and friends produce MPEG-2 video and MPEG-1 layer II audio. The video can be set up to record at a resolution and bitrate compatible with DVD-Video, but MPEG audio != AC3. This means that the audio must be transcoded somehow to AC3. On the first attempt, I figured I'd demux the source file, transcode the audio stream, and remux the streams with a sequence like this: lvedemux foo.mpg mv foo.mpa foo.mp2 ffmpeg -i foo.mp2 -ab 192 foo.ac3 mplex -f 8 -o bar.mpg foo.m2v foo.ac3 rm foo.m2v foo.ac3 This produced synchronization problems. Attempting to set an audio delay with the -O option to mplex didn't improve things any (it didn't help that lvedemux didn't retrieve audio delay information from the source file like DVD2AVI does). (I could've tried lvemux instead of mplex, but the "-f 8" option in mplex produces streams in the format dvdauthor needs.) I figured I might try mencoder next, since it would copy from one program stream to another. (I'd still need to figure something out to make the streams compatible with dvdauthor, but just getting a playab;e stream would be a start.) I tried it with a direct stream copy of the video and a transcode of the audio like this: mencoder -of mpeg -o bar.mpg -ovc copy -oac lavc -lavcopts abitrate=192:acodec=ac3 foo.mpg The video plays OK, but the audio is mangled beyond playability. Software decoding doesn't work, and when I try hardware decoding (-ac hwac3,), the receiver connected to my computer never kicks into AC3 decoding mode (it did with the first file). Changing "acodec=ac3" to a different codec (such as MP3) works, so it appears it's just AC3 encoding that is broken. :-( Has anyone figured out a method of transcoding audio while leaving the video alone and keeping the audio & video synchronized, all under Linux? I can do this easily enough under Windows, but doing everything under Linux would be nice from a standpoint of just popping a blank DVD-R into the burner on the MythTV box and saving some TV shows to it. Here are version numbers for the apps I'm using (names of the source tarballs from which they were built, because this is a Gentoo box): lve-040322.src.tar.bz2 ffmpeg-0.4.9-pre1.tar.gz mjpegtools-1.6.2.tar.gz MPlayer-1.0pre5.tar.bz2 _/_ / v \ Scott Alfter (IIGS( http://alfter.us/ Top-posting! \_^_/ rm -rf /bin/laden >What's the most annoying thing on Usenet?
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