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Old 30th March 2010, 08:05   #1502  |  Link
asc28
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Join Date: Jan 2009
Posts: 31
Quote:
Originally Posted by Mosu View Post
Can you please upload a source file for me for testing purposes? It doesn't have to be the whole file, but it should be long enough that the speed problem becomes obvious. You can upload to my FTP server (see my signature).

Also I need some more information:

1. Which program did you use for extracting the MPEG2 from the DVD? Do you mux the .VOB file directly with mkvmerge or has the video been extracted to separate MPEG2 elementary or program streams?

2. Which program do you use for playback? We know that older versions of ffmpeg (and therefore ffdshow) contain a bug that causes it to play video too slow or too fast.

3. "Video speed is not in sync" -- do you mean that the video plays slower/faster than the accompanying audio track?
Uploaded a sample to ftp (sample.mkv). It was muxed by 3.2.0 and plays at the correct speed. Demux the streams and remux with 3.3.0 to see the change.

Did some more testing and it appears the problem happens with tracks demuxed with PGCDemux, but not with DVDDecrypter. Unfortunately, PGCDemux is the new de facto standard since it does sup subtitles and more "proper" handling on cutpoints. Here's a word about the differences between the files they produce, which might be of help:
Quote:
PGCDemux calculates the delay properly for remultiplexing the audio and video directly, or with the newer avisynth programs. DVDDecrypter and SmartRipper calculate the delay for the old dvd2avi which dropped video frames.
The vidoe bytes that are different are probably the gop timecode. Since there are no fixed offsets in mpg that's only a guess. Look for the header preceeding the bytes that are different, it will be 00 00 01 xx - the xx will tell you what header you are looking at. B8 is the gop header, which contains a timecode. Some rippers give you the option to reset the timecode to start at 00:00:00.00
from this thread: http://forum.doom9.org/showthread.php?t=84778

1. PGCDemux, Elementary stream m2v
2. Tested MPC-HC's built-in decoder, ffdshow, DScaler's decoder, Microsoft's decoder. Splitter is latest Haali's
3. Speed is faster, duration is shorter. For example, a 23:04 file shows up as 19:39.
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