Deshaker, where to append 30 frames?

[RickA]

Greetings,

I've recently discovered Deshaker for VirtualDub. None of the guides I have come across so far have specifically stated where to append the extra 30 frames. Do we stick it on the beginning or the end of our original video for pass-2? I'm thinking if at the beginning would that not chop off an another 30 frames from the end?

After we have Deshaken and trimmed off the extra 30 frames with VirtualDub or VirtualDubMod will our video be back in proper sync with the audio previously stripped out by VDMod? Hoping someone who has more experience with this filter can clarify this for myself and future others that discover the filter.

Cheers,
Rick

[AlanHK]

Have you seen this page: http://www.codecpage.com/index_Deshake.html

We use a 1 second (25 frame) area to get filling data for the borders. This will delay the output video by 1 second, but not the sound. You may enter an audio delay value (1000 msec. /audio/interleave) in VirtualDub to compensate for this. Other ways to cope with it are cutting off the start second when encoding MPEG2 and inserting the audio separately, or, just doing a direct stream copy with VirtualDub, with 1 second cut off and audio delayed 1 second. This takes some time and space but works in any case.

I only very briefly experimented with this so I can't offer much practical advice.

[RickA]

Thanks on the reply AlanHK. I was referring to the part:

Special Considerations
One thing you will find if you followed the directions above, is that your stabilized video has thirty frames of blank video appended to the beginning, and the end is thirty frames short. This is explained in the Deshaker guide referenced at the above site. This is the result of Deshaker accessing past and future frames. You can easily fix this problem by appending at least thirty frames of video before starting Pass 2 (where you save the AVI file). To append video, click on File -> Append AVI Segment, and pick a short clip of just a few seconds. You need a clip that is at least as long as the Future Frames setting (which in this guide is 30 frames). If it is longer, it won’t make the final clip any longer. It doesn’t matter what is in the clip because the actual video isn’t used. This is simply a way to get around one of the few rough edges in the plug-in.


from this webpage http://www.sundancemediagroup.com/articles/deshaker_guide.htm

Cheers,
Rick

[AlanHK]

See http://www.guthspot.se/video/deshaker.htm -- the author's page

Previous and future frames to fill in borders
Since VirtualDub filters can't access future frames, the filter uses a little trick. It collects frames and delays the output by as many frames as you've set for future frames. This causes a couple of problems that can be dealt with pretty easily once you know how. First you need to delay the audio. You can do that in the VirtualDub menu Audio/Interleaving. While collecting frames, a text in the output video will tell you how many milliseconds to delay the audio. Second, you must offset the end marker in VirtualDub by the same number of frames. Otherwise you won't get the last few frames. If you don't have enough frames in the end, just append any clip. Those source frames won't be used for anything anyway. Note that this trick applies to pass 2 only, pass 1 should be processed without any offsets or appended clips.

So add to the end.

[zoobie]

as a sidenote, I didn't bother to crop since this was taken care of with the tv's overscan...turned out fine
for full frame internet, you probably want to crop depending how bad the shake is

[RickA]

Thanks guys, appreciate it. You helped confirm what I was thinking. Sometimes I have the bad habit of reading into something more ways then I should.

Cheers,
Rick