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onlyearth
26th December 2006, 11:28
I compress mpeg2 video to mpeg4 video with XviD and VirtualDubMod, but sometime the result video is't synchronization. I change the frame rate, it's a little well. Can you tell me the whys? Thanks~
Guest
26th December 2006, 14:28
VirtualDubMod does not support soft pulldown, so if the MPEG2 file has soft pulldown then the audio sync will be ruined. Try VirtualDub MPEG2 and set the MPEG preferences to enable "honor repeat-first-field" flags.

It's also possible that the sync is just off in your source file. How did you make it?
onlyearth
26th December 2006, 15:29
VirtualDubMod does not support soft pulldown, so if the MPEG2 file has soft pulldown then the audio sync will be ruined. Try VirtualDub MPEG2 and set the MPEG preferences to enable "honor repeat-first-field" flags.

It's also possible that the sync is just off in your source file. How did you make it?

Thanks! But very sorry that I do't know the "soft pulldown" and "honor repeat-first-field", can you tell me those? Thank very mach.:thanks:

Executioned source video is use a gatherCard. It's mpeg2 format.
Guest
26th December 2006, 15:37
Is it in sync if you just play the MPEG2 file?
onlyearth
30th December 2006, 12:07
Yes. It's in sync if play the MPEG2 file.
CWR03
30th December 2006, 12:42
It's not unusual for video files to become out-of-synch when encoding to MPEG-4, even if the original MPEG-2 file plays in synch. Try capturing with audio in .WAV format, or capture directly with VirtualDubMod.
henryho_hk
30th December 2006, 15:07
Or try DGIndex and encode to XviD through AVISynth.
ntz
4th January 2007, 07:24
How about if I use the video with XviD and its audio file through AVISynth and meGUI and then merge it with AVImux GUI? Is it a bad thing or not? Or is there should be some fps converting from Mpeg2 to other formats to synchronize the audio and video?
henryho_hk
4th January 2007, 12:32
You need to write an AVS script first if you want to use MEGUI. A single line "Directshowsource("abc.mpg")" may do the job if your computer has all necessary stuffs installed.

There is also a Virtualdub mod called "Virtualdub-MPEG2". Perhaps it can decode your MPEG2 file correctly.