Syncing video cuts to audio beats?

rvamx wrote on 2/11/2008, 9:54 PM
This may be an easy question to answer, but I just cannot find the answer anywhere. I am trying to sync / cut clips exactly on each beat of a music track. It works for some peaks in the audio, but some others are slightly off. The reason why this happens is because the cursor cannot be moved just "slightly" when zoomed in; it always jumps too far.

Is there a way to set how far the cursor moves? Small steps as opposed to large steps? Thanks.

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Comments

John_Cline wrote on 2/11/2008, 10:08 PM
In video, cuts must occur on frame boundaries, which in NTSC video are 33 milliseconds apart. You'll have to split the difference, if the beat occurs in the middle of a frame, you'll just have to cut on the frame boundary just to the left of the beat. Probably better to cut just a little early than late.
busterkeaton wrote on 2/11/2008, 10:21 PM
Simple solution, you don't need to cut exactly, precisely on the beat. The human eye will never notice it.

Detailed explanation. Your video is at 30 or 25 or 24 frames per second. When editing video the frame is your basic unit and 1/24 of a second is enough to fool the eye. Your audio is sampled at something like 44,000 cycles a second. To your ears 1/30 of a second is noticeable.

When you Quantize to Frames selected (and you do) you can only move the cursor a frame at a time. If you are using Vegas to edit audio, you can turn this off in the preferences.

The reason you don't need to be precisely on the beat, is when you make cut, there is a visual discontinuity. Your brain rapidly adjust for this disconitnuity, but if the beat is anywhere near the cut, let's say within 1/100th of sec, your brain is going to say they were basically simultanesously. That is, by the time your brain processs this new visual information it's not going to notice audio disparity.
Former user wrote on 2/12/2008, 8:45 AM
The Vegas cursor moves based on the zoom amount of the timeline.

If you want to force it to move one frame at a time hold the ALT key down while clicking the left and right arrows.

Dave T2