Software to fix varying audio

[kinglerch]

I use Sound Forge's Time Compress/Expand to correct the speed of an entire audio clip. But what software can I use if the clip doesn't have a consistant speed?

If I change the speed so the beginning is correct, the end is too fast. If I change the speed so the end is the correct speed, the beginning is too slow.

Is there any software that can help with this?

[mazinz]

you can still use soundforge. Unfortunetly for your problem, you have the fun and pain staking task of going through each section on the sound file (lets say break it up into 10min segments) and use the time compress, or even pitch, or even add/subtract milliseconds here and there to get your audio dead on with your video.

It sounds more not as if your video is out of speed, but that the actual video increases in speed as it plays. This is why you can match the beginning (or wherever) and the rest of the audio is still off.

I am currently in the process of doing something similar to you with some Japanese films and trying to get the english soundtrack to go with the jap picture. In this one case i have, the english version which keeps playing faster as it goes along, so the time compress/expand only helped so much. I then had to actually go in and fine tune each section (which is why i mentioned breaking up your audio file into 10 min segments) and then get a final wav file that matched the video (well im still working on that).
I too wish their was a simplier way to do this ( one ideal way would be if vcrs had a "pitch" control for the actual picture, then i could truly slow it down when i notice it starting to play faster then it's Japanese counterpart, i mean this by watching the 2 films side by side).

[kinglerch]

Is this true? No software exists to to do a variable speed change?

[mazinz]

another tool that recently came out (and is freeware) is called
SyncView . You can download it on this site This seems to combine the extend/compress sound option, along with being able to view your video as well.
According to the description for it, lets say you fix the beginning and you notice the sync starting to go out (towards the middle of the film). Supposedly this app will keep what you have already fixed and allow you to fix the rest as it goes on. Having the video to match with it is a plus.-- And that is why it excels, it really is doing the samething soundforge is but now you can actually view where/when you need to compress or expand the sound

What sucks though is that it is mainly for an avi file and wav. Be great if you could import an mpeg2 file to work with this. I would love to fully try it out ( i do not have the the time to)

[SDeC]

Mazinz,

Your intentions were probably good, but you should not advise members on software that you have not used, because you are likely to misrepresent the software (as you do here) and then confuse existing and potential users.

This seems to combine the extend/compress sound option, along with being able to view your video as well.

The latter is true, but the software does not alter media files. There is nothing in the description or on the website that speaks to audio stretching/shrinking. CoolEdit supports such operations.

According to the description for it, lets say you fix the beginning and you notice the sync starting to go out (towards the middle of the film). Supposedly this app will keep what you have already fixed and allow you to fix the rest as it goes on.

Are you sure you were reading the correct description? The software is a tool to determine the best audio-video offset times when encoding/muxing. The software is worthy simply because the user can see and hear the effects of different alignment values during pre-production. But if the audio file is messed up temporally, the user can only determine the best compromise (i.e., align the middle of the movie and allow sync to be off at the beginning and end of the movie).

When the software supports MPEG playback, it will be easy to also verify that the encoding/muxing operation is accurate in the first place (using the original, separate audio file and listening for echo against the finished MPEG program). This is related to the software's secondary intention to help identify the production stage at which a sync problem is originating. Sync problems manifest for different reasons, vary from user to user and from project to project. Many burned (S)VCD titles present sync problems even when there was nothing structurally wrong with the audio file. In such cases, the problem could be...

the audio-video offset times;
the encoder/multiplexor;
the player.

The SyncView program and the SyncTest media are generally sufficient to determine the origin.

Regards

- SD

[mazinz]

i was almost positive i typed up a follow up to my previous post, rather then going through and editing it. Hmm evidently that did not go through (was at work). At anyrate i realized i read the description wrong and posted as such (but as stated previously, that did not go through). I have not checked this topic since then, as i only/usually follow up on them when getting notifications in my email.