Trouble with Virtualdub rotate filter

[Vinnie Terranova]

Hi, a few weeks back I posted that I was trying to find a free video editor that can rotate sections of an mpeg2 clip. I guess there's no freeware that can do it though so I decided Id just have the clip be an avi and use Virtualdub to do the editing.

What I need to do is have a few sections of the clip rotate like 90 degrees from horizontal to vertical, then go back to regular display, then a little futher in the clip rotate again for a section, then go back to normal, etc. I figured I could use the Virtualdub filters (rotate, rotate2, or motion) to do this by using blend to apply the rotation to just to the frames I need rotated. So I figured out how to use blend and picked out the frames I needed rotated on the curve editor and 'highlighted' the section on the graph. But when I apply either of the rotate filters to the section, I get an error message saying it can't do it because the input size is different from the output size (the video is around 720x576 I believe). I think I got a little further using the motion filter (I could actually preview the rotate), but I still couldn't get it to save. I can't find any documentation or tutorials on how to use the motion filter to rotate sections at all so I was just guessing how to use it.

Can anybody please tell me if it's possible to do what I need to do with Virtualdub? Im trying to avoid having to cut my clip up into several pieces just to apply the rotate to the sections and then having to paste it all back together. I've been looking for a free program that can do several rotates on the same clip at the same time for over a month now. Id appreciate any help! Thanks.

[poisondeathray]

I've been looking for a free program that can do several rotates on the same clip at the same time for over a month now

You could do it in avisynth


I suspect the reason why it's not working "easily" for you is that you're not starting with a square block with even width & height. You have a rectangle. So you can't rotate and join without resizing.

[manono]

Hi, a few weeks back I posted that I was trying to find a free video editor that can rotate sections of an mpeg2 clip. I guess there's no freeware that can do it though...

As poisondeathray says, AviSynth.

http://avisynth.org/mediawiki/TurnLeft
http://avisynth.org/vcmohan/EffectsMany/EffectRotation.html

Doesn't cost a dime. You only need a brain.

[Vinnie Terranova]

Thanks for the replies. Im starting to think Im gonna have to learn to use Avisynth. I've already taken a look at how you write the scripts. I've just tried to avoid it because Im gonna have to totally learn from scratch and that brings more frustrations (on top of the past 2 months looking for a program (w/GUI!) that can do what I need for free).

Anyway, thanks again.

[jagabo]

You can just work in sections in VirtualDub then append all the sections together later. As indicated though, you'll have to crop/resize after rotating to keep the same frame dimensions.



A short sample with middle shot rotated and resized:

rot.avi

[Vinnie Terranova]

Jagabo, your example vid is exactly what Im trying to do. I wasn't doing the resize after the rotate so I think that will probably solve my problems with Virtualdub if I add the resize after. Im still getting used to how Virtualdub works! But thanks a lot for your help.

One more question- My original MPEG2 is around 5300 kb/s. When I was using Virtualdub to save it, I picked XVID and set it to 5300 kb/s. The results were pretty nice. But I think there might be a little room for improvement. Setting it to uncompressed AVI results in a huge file so I can't do that. Anyone have an opinion on what codec is the best to use? Im just trying to get it looking as close to the original MPEG2 as possible (and avoid it being a really huge file).

I've read a bunch of opinions about DIVX, XVID, etc. Most of the time people are praising them for being able to compress a lot and have a small file size. But my concern is more of being high quality and not a lot of compression so Im not sure which is my best bet. Anyway, thanks again.

[jagabo]

If you are going to use VirtualDub try Xvid in Single Pass, Target Quantizer mode (constant quality), with a quantizer of 2. That will give you very clean results and should still turn out with a lower bitrate than your MPEG 2 source.

[Vinnie Terranova]

Hey jagabo, thanks again for your help. I still haven't had time to go back and mess with it again, but Im going to soon (so I might be back here with more questions!). But I really don't think I'll have any more problems. Just wanted to say thanks again for your input.

[jagabo]

Good luck!