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View Full Version : Q: Using DGIndex timestamp analysis to create AVsync time map


Poutnik
6th January 2010, 18:57
Is there a ready or easy to use way to create any kind of A/V sync time map, based of timestamp analysis in DGIndex ?

AFAI understand, the Timestamp analysis show AV shift at MPEG2 key frames, but question is framenumber or timestamp of all listed key frames.

It looks to me key frames in MPEG2 are very frequent, every 12 frames (recorded by Leadtek winfast II, checked by virtualDub).
But I do not know if it is constant and a rule.

My DVB-T captures show often piecewise AV out of sync,
usually needed to fix by piecewise audio delay , or encoding directly DVR-MS with usage of autoresyncing DirectShowSource.

I want to create a av sync shift timemap, e.g. in Excel,
and generate by a script a serie of AVS trims, with different parameters for audiodelay and/or timestretch AVS functions.

( ProjectX or PVAStrumento ofte does not help it fixing AV sync of corrupted MPEGs, converted from DVR-MS ).

Poutnik
11th January 2010, 07:21
Interesting is DGIndex timestamp comparison of original MPG PS,
this time without big sync jumps, and MPG PS after PVAStrumento fixing.

On X axis is key frame order number.

http://img704.imageshack.us/img704/7606/dgindextimestamps.png (http://img704.imageshack.us/i/dgindextimestamps.png/)

rstarkov
17th June 2011, 01:18
Is there a ready or easy to use way to create any kind of A/V sync time map, based of timestamp analysis in DGIndex ?

Not sure if this would have done quite what you wanted, but I've recently created ResyncMpeg2Audio (https://bitbucket.org/rstarkov/resyncmpeg2audio), which takes DGIndex's timestamp analysis and produces an Avisynth script to resync the audio back to video.

It's far from being a user-friendly tool (being a command-line tool and requiring you to know your way around Avisynth...) but then video editing seems to have a lot of this :/