Changing an aspect ratio on DIVX

[diablo_jones999]

Hi, I was wondering if anyone could give me any tips on how to change the aspect ratio on a file when I convert to DIVX.

Heres the situation, I have a DVD player that plays DIVX files. I have some old TV eps I would like to burn to disk, and watch....but my TV is 16:9........and the files are anywhere between 1:1 and 4:3. Also some are MPEG and some are AVI, XVID, etc.

I was using the River Past video perspective tool for conversion. Its fine except that even though I tell it to give me a 16:9 output, the end result is never 16:9. Its different than the source file, but not what I'm looking for. I think its like 1:4 or something weird. Whats funny is it gives me want I want in the preview window, but not the conversion.

So, to sum up.......I wanna take some odd video files, and convert them to DIVX with a 16:9 aspect ratio........any tips?

Thanks for the help.

[jagabo]

For files you've already converted try use MPEG4Modifier to change the display aspect ratio. Your player may not respect the DAR though.

For future video you should resize the frame to match the DAR of the source and use square pixels. A 4:3 video should be resized to a 4:3 frame size like 640x480 or 512x384. A 16:9 source to a 16:9 frame size like 704x400 or 640x368. Note those are not exactly 16:9 but the nearest multiple of 16 because Divx works best with that. If you want keep the aspect ratio perfect resize to a perfect 16:9 ratio then padd to an even multiple of 16. For example 640x360 padded out to 640x368. Or crop down to 640x352.

Try using FitCD to get appropriate fame sizes. I use AVISynth and VirtualDub (or one of the variants) for encoding to Divx or Xvid. AutoGK is a good tool if you want something simple.

[guns1inger]

Also, make sure your player is set up correctly. A lot of aspect ratio issues seem to come down to incorrect setup of players and TVs in the strange belief that if you aren't filling the screen from top to bottom and side to side at all times then you are missing out on something. Smart people know this simply isn't true.

[manono]

Maybe, except that he says this:

So, to sum up.......I wanna take some odd video files, and convert them to DIVX with a 16:9 aspect ratio........any tips?

He never actually says that the source files play with bad AR, something that might happen if he tried to make them fill the screen by messing around with the AR in the player setup or in the TV. My take on it is that it's just another person that wants to butcher his videos so he doesn't see any black bars on his nice new widescreen TV set. I could be wrong, though.

[diablo_jones999]

Well, I would prefer to not have to watch the video with black bars on the right and left of the picture if I can avoid it. I have zero problems with letterboxed video.

[diablo_jones999]

damn...wasn't done posting.....anyways.........

Im also just wondering why I cant get the software to do what I need. I will freely admit I am pretty inexperienced with aspect ratios and such. I used to just do VCD conversions, but since my player supports DIVX, I figured I would try and do things differently. No matter what, this will end up as a learning experience.

Is there some sort of problem with taking a file to the 16:9 that im not aware of, and maybe thats why the software wont output it correctly?

[Xenogear900]

I have kind of the opposite problem. I want to make 16:9 videos into 4:3 videos, NOT BY STRETCHING THEM OUT as that looks bad when you watch it, but rather by selecting park of the video to watch. For example: Pretend this rectangle is the entire 16:9 video, but I want to make it full screen. I'd need to get the area inside the x's. How can I do this? I'm using a TV Out with automatic fullscreen, so the zoom features of Media Player Classic and VLC won't apply on the TV screen.

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[jagabo]

There are two ways you can make a 4:3 video into 16:9: crop the top and bottom away or stretch it horizontally.

Conversely, there are two ways to make a 16:9 video into 4:3: crop the sides away or squish it horizontally.

[Xenogear900]

How do you crop the sides away? Can you do this without re-encoding the whole thing?

[jagabo]

How do you crop the sides away?

Just about every video editing program has a cropping function.

Can you do this without re-encoding the whole thing?

No.

[Xenogear900]

Is there a crop feature in virtual dub?

[jagabo]

Is there a crop feature in virtual dub?

Yes. Cropping can be added to any filter. Go to Video -> Filters -> Add -> Null Transform (or any other filter). Then back at the filter dialog select Cropping. If you add cropping to any other filter, the cropping will take place before the filter.

[Cornucopia]

Yes.

Just about every filter used also allows "Cropping" to be set (in the Add/Delete filterchain dialog).
It's accepted practice (and clearer to debug) to use it only when applying a "Null Transform" filter (which does nothing).

Scott

edit: jagabo, you beat me!

[jagabo]

Yay!!! I win!!!