Encoding with an aspect ratio of 2.5 to 1 HELP!

[Paulcat]

I have an avi file, 640 x 256 that I want to stick on a DVD. The problem is that the aspect ratio for that is 2.5:1 and TMPGEnc will only allow me to make an M2V file of 2.21:1

I have made a test file at 2.21:1 without cropping, and the resulting DVD is not too bad, with the people being ever so slightly elongated. Is there a way to alter the playback of this file to play at 2.50:1 or do I have to re-encode and crop out some of the picture?

Can I edit the M2V file itself or can I use PgcEdit or MuxMan to alter the final DVD files to change this?

(or is there a setting in TMPGEnc where I can custom make the resulting M2V in any aspect ratio I want?)

Paul

[Mug Funky]

mpeg-2 may support loads of aspect ratios, but DVD only supports 4:3 and 16:9. you'll have to add black borders and encode as 16:9 anamorphic if you want a DVD.

[Paulcat]

The Lord of the Rings DVD's are 2.21 to 1 and Shawn of the Dead is 2.5 to 1

I am using TMPGEnc which will allow me to encode 2.21 to 1 but no greater AR than that. It also allows a DVD format of 4:3, 16:9 AND 2.21:1. I can crop an image but cannot expand it to add border, at least not in any settings I can find.

[EDIT]

Instead of selecting full screen (keep AR) in the display options, I can select the no border option, or the custom size option. I assume the custom size will allow a 720 x 288 M2V file (2.5 to 1 AR) but I don't know how that will look or whether MuxMan will allow it. More later after some tests...

[Paulcat]

The latest test was cropping the original avi to 2.35:1, setting the source AR as 2.21:1 (slightly squashing the picture), setting the encode method to no border and the DVD type as 2.21:1.

MuxMan flat out refused to mux the video (error sd ar or something, eg the aspect ratio was off). TMPGEnc DVD Author muxed it fine, but playback was 16:9, horribly mangling the picture.

The M2V file played back at the correct AR, but there must be a flag in the file that it is meant for a 2.21 DVD which messed up MuxMan.

All I want to do is encode this AVI without wasting bits on encoding the black borders, or as little of them as possible.

Some more help please...

[mpucoder]

DVD is a subset of mpeg, it does not support or allow everything that can be done in mpeg. Among the things not allowed is DAR other than 4:3 or 16:9. There are also only 4 resolutions allowable, 720x480, 704x480, 352x480, and 352x240 (for PAL replace 480 with 576, and 240 with 288 for vertical size).
In order to make a DVD from video other than one of the two DAR's is to resize and border (ie letterbox) the video to fit the closer DAR. So if you want to create a 2.21:1 you need to resize it to be in aspect at 16:9 (1.77:1). That means vertically rescaling to 1.77/2.21, which is very nearly 4/5 or 720x384 for NTSC. Then center the image on a 720x480 canvas (ie add 48 lines of black above and below).