How fast should Vdub resave after a cut?

[tyee]

I captured an avi file (via .avs) to HD. Selected Mark in and out points. Selected Direct Stream Copy, then File, Save As. It starts saving at 25fps, which is about real time.

Isn't this just a basic file copy! File copy should be a lot faster than 25fps. When I join 2 avi files in Vdub I get over 1000fps. What's going on here?

[squid_80]

I captured an avi file (via .avs) to HD. What exactly do you mean here? If you mean you've opened an avisynth script in virtualdub, direct stream copy isn't going to work and you're actually getting uncompressed output.

[tyee]

Hi squid_80
Yes, I did capture a DV avi file to my HD, then used it in the avs script as AVISource(filename.avi). Now I want to cut it at a few places and save these shorter sections to new avi files, and I want to do it fast. Can it be done with any program?

Like I said, if I join 2 divx files together (which are obviously compressed) and use Direct Stream Copy, I get over 1000fps.
What the difference here?

[foxyshadis]

You should use avsp avisynth editor instead. You can do some very basic virtualdub-style editing on it, without saving the uncompressed file to disk.

The difference is that the script is getting decoded and processed before virtualdub ever sees it in this case; there's no smarts to pass through the original file. That's why every frame is listed as a keyframe, too.

[tyee]

Thanks foxyshadis. I downloaded AvsP and l see there's a Trim Editor. Is that what I should use. Doesn't this just add a trim command to the script or can it really save a new trimmed avi for me?

[foxyshadis]

You can't use avisynth in any way if you want to keep the original file, without re-encoding. You must work on the file directly in virtualdub or avidemux.

[tyee]

foxyshadis
Basically I'm using avisynth to run pulldown(x,x) manually on my avi file to find the proper sequence to use. I then wanted to save that section to a new avi file, then do the same for the rest of the avi file, saving all these sections with the proper pulldown(x,x).

You may say I should just use an IVTC filter and be done with it. I did try TIVTC and it seems to work fine, but I was wondering if the above technique would also work.

Any other thoughts come to mind?

[foxyshadis]

You can certainly do any filtering you need to, but when you do you have to re-encode, no matter what you use to filter it. Just expect that anytime you change the video beyond merging or cropping, you take a large speed and quality hit.