Changing audio speed

[Brain Champagne]

I'm trying to get my audio synched up. Someone once told me that the best place for the camera is often the worst place for the microphone. And in my case it's true.

So- I am trying to use audio from a different source and the speeds are very slightly different. I have the beginnings synched perfectly. Toward the end I stomp my foot- it sounds like a door slam and is something I'm trying to use to synch the two because it's a loud sound short in time.

Doing it visually doesn't work because VideoStudio (version 2) doesn't preview the video properly. So I had the idea- don't mute the source audio so I have both playing. Then render an audio-only file and listen to hear how far apart the two stomps sound, and adjust the audio track's speed.

I've shortened it by 2 frames and 10 frames but it still sounds exactly the same. Is there a bug in the audio-shortening feature or am I missing something? I tried using Audacity to shorten the audio but that didn't work well either, because it rounds off, and 2/30th of a second over 30 min is a tiny fraction.

[BrianCee]

When you shorten the audio track are you holding down the shift key - that is - do you select the audio block - go to the right hand end - and hold down the shift key while you slide the yellow bar at the end to the left.

Any other method of shortening the sound track simply cuts the end of the audio off and does not change the speed

[Brain Champagne]

I right-clicked on the audio track and chose Change Speed- I was hitting the down arrow next to the time (min, sec, tracks)- does that just cut things off? Or are you asking if I just cut the clip on the timeline? (I did not)

How else would I change the speed?

[BrianCee]

As long as you don't actually cut the clip it should work - I prefer the shift-slide method but using the change speed window should also work - both work for me I can see the actual audio block change length.

Are you allowing for the fact that the actual displacement of sound in the audio track in incremental throughout it's length - for instance if you were trying to sync a sound which was half a second out in the middle of a 10 minute video and shortened the audio track by half a second then at the half way point it would only change a quarter of a second - not half - if you follow me

Are you doing it in audio mode (sound mixer) so that you can see the sound waveforms - If you grab the black space just above the timeline (cursor changes to two parallel lines) and push up screen and also zoom in on the timeline the waveforms become quite large and make syncing easier

If the change speed is not working perhaps you could cut a piece out of the audio track in a quiet position and resync the second half on the thud.

[Brain Champagne]

The thud is almost at the end of the video so there's not much to allow for.

It's not just the thud I need synched, I can't have my lips out of synch anywhere on the video, it looks terrible, so cutting a fraction in a quiet portion isn't an option.

So anyway I used audacity and got the audio the right speed, rendered an audio file where there's just one thud even though there are two audio tracks (in other words, it's synched right) then when I muted one audio track and rendered a wmv file the synching is way off...

And to add to this, it crashes when I try to render video with cropping, I had to run a separately rendered video file, cropped, then paste that one back into VS and work on the audio...

I'll try rendering a file with a different format, then put that in VS and render a wmv file.

So you see why I really hate this program...

Thanks for the help.

[skier-hughes]

What are the source file types?
It may be that the audio recording might be better off being converted to the same type as used in video if it isn't and see how that goes.

[Brain Champagne]

AVCHD MTS file from a Canon SD card video camera.

Audio is WAV from a Zoom H2 audio recorder.

I got it working by changing the audio speed using Audacity, via trial-and-error until it looked right. It worked for creating an HD MPG file. It remains to be seen whether it'll work correctly when I create a WMV file, because last time it didn't. I'll post when it's done, later today.

[Brain Champagne]

GRRRR!

So, the hi-def rendering worked just fine. I tried making a wmv file and that had the audio and video out of synch.

So- I took the rendered hi-def file, which didn't have a separate audio track (since it was rendered into one file) and put that in VS to render a wmv file and AGAIN the audio and video are out of synch.

It should be simple- the whole project is just one mpg file, no split audio or anything...

Any ideas?

[BrianCee]

Have you tried to do the conversion in Windows Movie Maker - should be somewhere on your computer - comes free with windows - and is *supposed* to be the definitive programme for .wmv files.

[Brain Champagne]

That's an idea. Although I bought VS to get away from WMM! (and that was the XP version which I'm told is a lot nicer than the Win7 version- my computer now is Win7).

First I'm going to try to make a low-def file that's not wmv but another format. Because I need the low-def one for youtube and they're not particular about formats. If that doesn't work I'll try WMM, thanks for the suggestion.

[skier-hughes]

what setting did you use on the zoom?
I think choosing 16 bit 44.1khz wav should match most closely to the camcorders audio.

[Brain Champagne]

I think that is the audio setting on the Zoom recorder.

So, nothing seemed to match the audio to the video when I rendered a small file, regardless of how I tried it.

Had the idea to try a different media player- I simply copied the file back into VS and it seemed to play right. Tried a different media player and that was closer.

What I'd been doing with Windows Media Player is to open the file and skip to near the end and play. Maybe it's the player. So now I'm uploading the smaller wmv file to youtube and if it plays there, I'm set.

Kind of surprised that it might be the player that's at fault, so I'll stop blaming Corel and do what everyone does, blame Microsoft.

[skier-hughes]

I think isn't much good when the zoom has about 10 options to choose from
Checking other players is a good idea.