ATI Letterbox capture

[Nelson37]

Haven't seen anybody trying this, but I'll give it a shot.

ATI MMC has a display option for letterbox, this will correctly capture a letterboxed movie and overlay the black panels with new ones. This neatly covers the tv station logo and also the larger "you are watching" blurbs which I find extremely annoying. Wonderful, right?

BUT, when using this option, the resolution is changed from 720x480 to 640x480. I thought at first this might just be a typical MMC behavior, but I changed the res, exited and reopened, tried a few different sequences, no dice. Using the letterbox option forces resolution to 640x480. This would require a re-encode, though a header edit as with SVCD might work.

Anybody tried this, and more importantly found a way to force res to 720x480? Or is there a better way?

[Sulik]

It's possible to force any resolution by editing the preset in the registry, but it will probably be lost every time the preset is re-edited.

The custom MPEG presets are located under:
"HKCU\Software\ATI Technologies\Multimedia\Features\TV\Video Capture\MPEG".

You can change the cropping factors ("Horizontal Cropping" and "Vertical Cropping"). The values are in a 100% of the capture width, ie: crop 5% = "0.05"

[Nelson37]

Thanks, I figured it would be something like that.

Strange that ATI would set it up this way.

[Nelson37]

Nope, that ain't it.

The settings are in the Display area, not in the capture area. I saved and imported the keys to check this.

None of the capture settings have any affect when video is set to letterbox in display. Interesting.

This is absolutely perfect for cutting the station logos and announcements while doing a real-time MPG, if only the resolution were correct.

Still looking into this.

[vhelp]

Just curious.. what MMC version ??
-vhelp 3541

[Nelson37]

MMC version 8.1.

This is really frustrating. There is an aspect ratio key in the Display settings in Registry which seems to control this. At 4:3, it gives 720x480 without cropping. At 2:35 to 1, it crops almost perfectly, and overlays the letterbox area with a black mask. (I think the decimal values are 29 and 24, but I'd have to check this) BUT, the resolution is 640x480!!!

Crap, Crap, Crap!!!