4:3 AVI to DVD Questions

[Flarch]

I come across a lot of AVI files which are 512 x 384 @ 29.97 fps with MP3 audio. Most are DIVX or MSMPEG and fairly short.

I would like to put several on a DVD with a simple menu.

I figured that if each was processed separately into a DVD compatible stream, they could be burned with Toast using it's built-in DVD menu creation.

What is necessary to reencode from 512 x 384 to 720 x 480 mpeg2 and get the aspect ratio correct?

Also, does it matter whether the audio is mp2 or AC3?

Any other hints on the process would be greatfully accepted as well.

[junkmalle]

Just stretch 512x384 to 720x480.

[Flarch]

Um... that doesn't address either question.

What about the fact that the AVI 512 x 384 resolution = 4:3 aspect, while the DVD's 720 x 480 = 3:2 aspect?

A 3:2 aspect would be 512 x 342 or 640 x 384. I don't know how 4:3 aspect (TV) shows are typically encoded on DVD.

I notice mpeg2enc has a 'Letterbox' checkbox as well as a 'Set 3:2' checkbox if used to go to MPEG2 [.mpg], where ffmpeg does not.

On the other hand, choosing mpeg2enc's MPEG2 [.mpg] setting has no manual specification for letterbox settings, where ffmpeg's MPEG2 [.mpg] setting does.

In addition to those, there is an MPEG-TS [.TS] ffmpeg setting which has the manual letterbox settings. I'm not too clear on what an MPEG-TS is (transport stream?) or whether it would burn in Toast.

I am going to research on my own further, but it would be nice if somebody could write a line or two about the behaviors of the different settings and which is the best combination to create a DVD where the picture isn't stretched or squeezed and quality is best possible played back on different setups.

[Case]

AVIs use square pixels, DVDs don't. DVDs with frame sizes of 720x480 and an aspect ratio setting of 4:3 get streched to full screen on a 4:3 tv. DVDs with frame sizes of 720x480 and an aspect ratio setting of 16:9 get streched to full screen on a widescreen tv, and get auto letterboxed on a 4:3 tv.

[alph]

What this means is that since your source is 4:3 that you have to stay in 4:3. Although you set the values to 720x480, you need to make sure you the autosize to DVD, or 4:3. When played on a 4:3 TV it will fill the screen and when played on a widescreen TV it should appear as 4:3 with black or grey columns on either side. There is no need for letterboxing which is adding horizontal bars above and below the image.

Alph

[junkmalle]

Also, does it matter whether the audio is mp2 or AC3?

To be fully compliant with the NTSC DVD spec the audio should be AC3. But in reality, just about every player can handle MP2 (or even MP3) audio. MPEG audio is valid for PAL DVDs.

[Flarch]

I set ffmpegX for mpeg-2 DVD output minus the actual authoring but Toast rejected the test result.