DVB movie demuxing problems??

bcsman · 7th May 2005, 05:30

I've tried numerous programs and am having problems demuxing a movie recorded from my DVB card. I first used MyTheater to record the MPEG2 stream and when using both ProjectX and PVAStumento I got lots and lots of dropping GOP messages and the end video was not worth watching. Read where a TS stream was better so installed Alt-DVB and recorded the movie in .ts format. Used ProjectX to demux and once again there were lots and lots of dropping GOP messages. When I got done the 2 hour movie file was compressed into a 33MB file and played like it was being fast forwarded.

Am I doing something substantially wrong here?? My DVB signal is over 90% and when I played the recorded MPEG2 file it was really good straight from the original recording. I don't have anything that plays the .ts file so I'm not sure how that original file looks. ANy help out there??

Do I really have to demux at all or can I just find a program to author the .ts recording because the demuxing appears to be where I'm having my problems??

drmpeg · 7th May 2005, 10:48

ProjectX has a difficult time with certain streams (streams without
any GOP headers and timecode at all, which is legal in MPEG-2, are the
worst) due to it's A/V sync maintenance algorithm (that I believe relies
on GOP timecodes).

You can try my cheapo command line demuxer. It will re-insert missing
GOP timecodes in the demuxed video elementary stream, since many other
authoring tools require GOP headers and timecode. However, it only
does A/V sync at the beginning of the TS file, so it's not as nice
as ProjectX for maintaining A/V sync with bitstreams that have errors.
It can be found here:

http://www.avsforum.com/avs-vb/showt...81#post4615081

If you need any help using the tool, post here.

Ron

buzzqw · 7th May 2005, 10:53

you can also try dgmpegdec 1.3.0

has a very good demux fuction

BHH

yanyani989 · 14th May 2005, 02:22

@drmpeg
thank you very much for your program!
I can finally demux my Disc-HD (and occasionally other) stream after days of frustration with ProjectX.
But what would you recommend if I suspect my streams contain errors? (how to check btw?)
I've tried mpeg2repair (http://users.adelphia.net/~mwilczyn/mpeg2/), but tests so far seem to suggest that it worsen the unsynch problem rather than helping. (I tried feeding a few raw and fixed streams to tsdemux then to Mpeg2Schnitt and compare the final product.)

@buzzqw
I've tried DGmpgdec, the demux worked, but when I import into Mpeg2Schnitt, it report error when it came to the end of the stream (the msg is "Fehler bei Bereichsprufung."). Then I tried with Cuttermaran, it imported without problem but when I tried to set cut in, it just keep reporting "No GOP in front of I-frame", no matter where I set it. I guess I know why this is happening after drmpeg's explaination.

7th May 2005, 05:30	#1 \| Link
bcsman Registered User Join Date: Jan 2005 Location: Michigan Posts: 24	DVB movie demuxing problems?? I've tried numerous programs and am having problems demuxing a movie recorded from my DVB card. I first used MyTheater to record the MPEG2 stream and when using both ProjectX and PVAStumento I got lots and lots of dropping GOP messages and the end video was not worth watching. Read where a TS stream was better so installed Alt-DVB and recorded the movie in .ts format. Used ProjectX to demux and once again there were lots and lots of dropping GOP messages. When I got done the 2 hour movie file was compressed into a 33MB file and played like it was being fast forwarded. Am I doing something substantially wrong here?? My DVB signal is over 90% and when I played the recorded MPEG2 file it was really good straight from the original recording. I don't have anything that plays the .ts file so I'm not sure how that original file looks. ANy help out there?? Do I really have to demux at all or can I just find a program to author the .ts recording because the demuxing appears to be where I'm having my problems??

7th May 2005, 10:48	#2 \| Link
drmpeg Registered User Join Date: Jan 2003 Location: Silicon Valley Posts: 455	ProjectX has a difficult time with certain streams (streams without any GOP headers and timecode at all, which is legal in MPEG-2, are the worst) due to it's A/V sync maintenance algorithm (that I believe relies on GOP timecodes). You can try my cheapo command line demuxer. It will re-insert missing GOP timecodes in the demuxed video elementary stream, since many other authoring tools require GOP headers and timecode. However, it only does A/V sync at the beginning of the TS file, so it's not as nice as ProjectX for maintaining A/V sync with bitstreams that have errors. It can be found here: http://www.avsforum.com/avs-vb/showt...81#post4615081 If you need any help using the tool, post here. Ron

7th May 2005, 10:53	#3 \| Link
buzzqw HDConvertToX author Join Date: Nov 2003 Location: Cesena,Italy Posts: 6,552	you can also try dgmpegdec 1.3.0 has a very good demux fuction BHH

14th May 2005, 02:22	#4 \| Link
yanyani989 Registered User Join Date: May 2005 Location: NYC Posts: 9	@drmpeg thank you very much for your program! I can finally demux my Disc-HD (and occasionally other) stream after days of frustration with ProjectX. But what would you recommend if I suspect my streams contain errors? (how to check btw?) I've tried mpeg2repair (http://users.adelphia.net/~mwilczyn/mpeg2/), but tests so far seem to suggest that it worsen the unsynch problem rather than helping. (I tried feeding a few raw and fixed streams to tsdemux then to Mpeg2Schnitt and compare the final product.) @buzzqw I've tried DGmpgdec, the demux worked, but when I import into Mpeg2Schnitt, it report error when it came to the end of the stream (the msg is "Fehler bei Bereichsprufung."). Then I tried with Cuttermaran, it imported without problem but when I tried to set cut in, it just keep reporting "No GOP in front of I-frame", no matter where I set it. I guess I know why this is happening after drmpeg's explaination.