Synchonizing two videos of different/mixed frame rates

[Baltyshark87]

Actually, i don't know where to start. I have two same cartoons in different formats - VHS and DVD. On VHS i have an audio which i want to synchronize with video that is on a DVD. These two formats (VHS and DVD video) have different frame rates. I was synchronizing cartoons before and I have never come across this problem. Usually I used to stretch/shrink audio of digitized VHS to match the video (from DVD). But now one of these formats seems to accelerate at times an than slowing down - well, it looks like the video itself has a mix of different frame rates which makes it impossible to synchronize audio to video just by stretching/shrinking it. Now i want to know it there exist a program that can match two videos of different frame rates, maybe by selecting points in same parts of cartoon so that a program can calculate and render video of same frame rate to original one. Or is there any other solution? Thank you all in advance for helping me out.

[Cornucopia]

Framerate usually doesn't make a difference (unless you are trying to mix & match video while editing, then it almost always makes a difference).

What matters is the content and its running time. Is the content (shots, scene lengths, order) the same? If so, the running times should be the same regardless of framerate.
If you have a title that is EXACTLY 1hour,0min,0sec,0frames and has a version that runs at 30fps, it should still be the same length (+/- 1 frame) as that same EXACT version of the title but running at 25fps.

Since audio DOES NOT have a "framerate" (not counting internal packetizing of compressed formats) and just has a samplerate (usually 44.1kHz or 48kHz) and bitdepth, if you have 2 copies of the same running time, they should be easily syncable.

AFAIK, there is no specialized tool.
ANY decent NLE should be able to load multiple titles (of possibly differing video framerates) and line them up based on significant momentous instantaneous events (e.g. an edit cut, a lightning bolt, an explosion). Use an NLE that supports track layers, start visually and roughly, then move down to more and more granular/finer timebases, shifting back and forth in time until you find the closest sync. On better NLEs, you will be able to then change the timebase to sub-frame levels based on audio samples or groups of samples (e.g. msec). Once you've zoomed down far enough you should be able to refer to the audio waveforms for syncing rather than the visual frames. In this way you can sync them down to the exact sample (+/- 1 or 2 samples), which is EXACT as far as viewing, listening and editing is concerned.

Since every title or set of titles is different, there is no real shortcut to this. I would guess an AVISynth-type script could be created to assist with this for matching within a certain tolerance to take away some of the early guesswork, but it would likely require a bit of setup & tweaking, mitigating much of the real assistance it could give.

If your clips are different, they are different, and in that case, you wouldn't be able to be sure that was is required is slipping in time, shrinking/stretching, or editing. Unless you MAP them out in detail.

Scott

[manono]

These two formats (VHS and DVD video) have different frame rates.

Not unless one is PAL and the other is NTSC. If both are the same then they're both either 25fps (PAL) or 29.97fps (NTSC).

Now i want to know it there exist a program that can match two videos of different frame rates..

If one is PAL and the other NTSC, then your usual method of stretching to fit will work. Maybe you have to also take into account a delay.

I'm inclined to agree with one of Cornucopia's theories - that there may be differing frame counts involved. Short video samples of the 2 sources should prove helpful, but this project might be more trouble than it's worth.