Question About Widescreen, I Think, Two Xvid Encodes

[hech54]

Here's the scoop.
Two Xvid encodes. One (called "correct") when shown on TV and computer has the proper
black bars top and bottom of the screen...all looks normal.


This one below(called "incorrect") has no black bars top and bottom and the picture
is basically full screen. Both are from the same source - encoded by a friend.


What happened?
Can this be fixed or am I stuck?

[jagabo]

The first one is letterboxed (it has a ~720x400 image with 88 lines of black top and bottom) and should have the DAR flag set to 4:3. The second one isn't letterboxed but should have the DAR flag set to 16:9. Use MPEG4Modifier to do so.

Note, not all players will respect the DAR flag.

[hech54]

THANKS!!!!
I couldn't think of the name of that damn tool.
It works.....so far.....at least on the computer anyway. I'll
try on my HDD to TV (Trekstor Movie Station) tomorrow.

[Jim44]

The first one is letterboxed (it has a ~720x400 image with 88 lines of black top and bottom) and should have the DAR flag set to 4:3. The second one isn't letterboxed but should have the DAR flag set to 16:9.

Just curious, as I'm still learning AR stuff, how did you determine this info? From the Gspot caps (they look the same to me), or from experience dealing with this stuff and hech54's description?

Thanks.

[jagabo]

I used a combination of the GSpot posts, hech54's description, and knowledge of common mistakes made in creating Xvid AVI files.

The first video had a 720x576 (5:4) frame but a square pixel encoding (1:1 PAR). Hech54 said it played back with "proper black bars top and bottom". That means the black bars are part of the picture. The implication is that this was a 16:9 video letterboxed in a 4:3 DAR frame (typical of a widescreen cap from VHS tape, for example). He probably didn't notice that it was playing back with a 5:4 aspect ratio (because 4:3 DAR wasn't flagged) rather than 4:3.

The second had the same properties according to GSpot but Hech54 said there were no black bars. He didn't mention if the picture looked squished horizontally but I guessed it was. Since the frame size was 720x576, typical of a DVD rip, I guessed it was a a DVD rip, not corrected for square pixel encoding, but also not encoded with the 16:9 DAR flag.

[Jim44]

Thanks for the explanation, jagabo! I'm starting to get the hang of it.