Where to put letterbox

[4evrplan]

I've got a standalone dvd player that supports divx/xvid. I noticed, when I encode a video with AGK with standalone compatibility turned on, the dimensions are divisible by 16, so for 1080p sources, the result is 1088 pixels high.

My question is, how do these players display a 1088 res source? Does it resize it on the fly, show only the middle 1080 scan lines, or show only the first 1080 scanlines and cut off the last 8?

The anser to that question will determine if and how I add letterboxes to my video to get it to display correctly on a 1080p HDTV.

Or worse yet, is this not standardized and different from one player to another?

[henryho_hk]

Can those standalone handle 1440x1080 or 1920x1080? Are AutoGK's standalone compatibility settings for DVD-sized materials?

[Ghitulescu]

the last 8 lines are cut, they probably will contain only black pixels.

[4evrplan]

Can those standalone handle 1440x1080 or 1920x1080?

I'll see if it can at least play it. I can't do a proper test 'cause my HDTV died, and I'll have to try on an SDTV, but I'm going to try to "future proof" my videos anyway.

the last 8 lines are cut, they probably will contain only black pixels.

They'll definitely contain only black pixels when I'm done with my editing. If it's the last 8 lines that get cut, then that's where I'll put the extra.

Of course, that means I've got to do about two days worth of encoding over again.

[4evrplan]

Okay, here's a related question. What do standalones do with source that is 1920 by y where y is less than 1080? For example, will a 1920x1040 video be centered (20 black scanlines top, 20 bottom), stretched to fill the screen, or just drawn at the top with 40 black scanlines at the bottom?

[Ghitulescu]

Each standalone does it differently. Test yours yourself.

[4evrplan]

Each standalone does it differently. Test yours yourself.

The idea is to try to get predictable behaviour regardless of which standalone is being used (like I said, "future proof").

If this isn't standardized, then perhaps it'd be best to include letterboxes encoded into the video itself to force the player to center it. It's inefficient, but it's better than dealing with undefined behaviour.

[CWR03]

The idea is to try to get predictable behaviour regardless of which standalone is being used (like I said, "future proof").
Try encoding at 720P with letterboxes added where necessary to make it 1280 x 720 (both evenly divisible by 16), unless you're absolutely stuck on maintaining as close to 1080p resolution as you can.

[Ghitulescu]

There's no future proof in a field where new formats are invented every 10 years to force the consumer to pay once more for the same item but in a different packaging.
Generally speaking each new format allows the use of the previous format (like VCDs could be imported into DVDs, DVDs into BDs) so your're safe one generation. However, I'm not sure how many people still watch VCDs :) or even the AVIs they created from DVDs in the late '90ies ...