DVD to XviD/AVI: Aspect ratio is off

[milkydoo]

I've done some searching and reading, including this AR guide: https://forum.videohelp.com/viewtopic.php?t=174200

I still have some things I need clarified.

Where I'm at right now: I've taken a DVD and used GK to convert to XVID. I started with AGK and probably should have stuck with that but decided to try it manually, and I've run into a problem. Oh well, it's a chance to learn something.

The quality and sound are good, but the aspect ratio is off on the vertical, when played on WMP and InterVideo DVD player. It's too short. The black bars are only about 1/2 inch tall when playing the DVD, but are about 1 1/2 inches tall (each) when playing the AVI.

The AVI resolution is 640x352, which calculates to about 1.81.

So, I assume I screwed up with GK by not manually selecting a proper resolution? I guess I assumed it would try to maintain a resolution that would match the OAR.

So I read in the guide that with AVI's, the aspect ratio is set by the resolution, whereas with mpg's, a flag is used. But I also have read here that Mpeg4modifier can set a flag in AVI's, it's just that most players will probably ignore it?

What is my best bet here if I want the OAR and maximum player compatibility? Let me guess: I need to reencode? Or can I remove the AVI container, leaving an mpeg4 extention (?) and just set the flag to the desired ratio?

And another question: I read in that guide that it's best to crop out letterboxing from the DVD for a more efficient conversion, but how do I tell if the converted file has encoded letterboxing? A cropped, widescreen file, played at the proper aspect ratio, will appear to be letterboxed, even though it's not actually encoded that way.

Thanks for helping another newb.

[celtic_druid]

The flag works fine in an avi container since it really has nothing to do with the container. As for most players. Couldn't say. Who cares though as long as it works on your SAP. Works fine here on my cheap MTK based player.

If you open the file in VDub you will be able to see if there are any borders. Should also be obvious when you are cropping.

What was the actual AR of the source? Also there is a reason behind 640x352 instead of 640x360 which would actually be 16:9 and that is because using mod16 resolutions are more efficient.