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Dr Spaulding
05-05-2005, 10:02 PM
is there a program that can reduce the size of an avi/mpeg file. like you can choose the quality/screen size etc and thus reduce the file size?

Assmunch
05-08-2005, 01:12 AM
Try Im Too mpeg converter or win avi converter. I think the former can probably do what you want it to.

muchspl3
05-08-2005, 04:25 AM
kvcd :cool:

RealitY
05-08-2005, 06:17 AM
For mpeg/avi to avi DrDivX is fairly simple to use...

lynx
05-08-2005, 09:46 AM
Depends how much space you need to save. Re-encoding the video stream is not a good idea and takes an awful long time, so avoid doing it if you can.

Here's a couple of tips for avi files where you only need to save a little space. I do all of these with VirtualDub or VirtualDubMod.

First thing to do is look at the audio/video interleaving, quick and easy with no losses. Set both Audio and Video streams to direct stream copy.
The default setting is to preload 500ms and interleave audio between every video frame. That wastes quite a bit of space, often about 5% of audio stream size. I usually change that to 1000ms preload and interleave every 500ms which usually reduces the overhead to under 0.5% so it saves about 4MB on a 100MB audio stream.

Secondly, you can trim off some or all of the credits. Static credits don't take up much space since there's no change between frames so you may not save as much as you hoped, but rolling credits are jut like any other video stream. Don't forget to set the interleave otherwise you'll go back to defaults. Set both Audio and Video streams to direct stream copy, it's another quick and easy fix.

Thirdly, you can re-encode the audio. If you load the file in VirtualDub and get a warning about improper VBR audio encoding you should probably do this anyway, otherwise you will almost certainly have problems with loss of sync. Audio re-encoding can be much more complicated (since there are so many possible combinations) so I don't intend to go into it here. Anyway, the file information will tell you the audio bitrate. At 192k, 1hr of audio takes 86MB but only 72MB at 160k, a 16.6% saving. You can decide for yourself how much you want to save.

I believe you can do similar things with TMPGEnc for MPG files, but I haven't tried them myself.

Remember: avoid re-encoding the video stream if possible, don't be tempted to use VBR audio encoding otherwise you'll have sync problems, and always change the interleave.