If anyone can shed light on this it would be appreciated. As I understand it, resolution for 16:9 with a 1080i monitor is 1920x1080 where 1920 can be calculated by:
1920 = (1080 / 9) * 16
Does this hold true for 4:3 also. E.G. Is horizontal resolution for 4:3 aspect ratio with 1080 lines of vertical resolution 1440?
1440 = (1080 / 3) * 4
If both of these are true, is it possible, and is there a video card that will
produce 1920x1080i and/or 1440x1080i? If so, does anyone have
modelines for each these?
Are the h and v sync timing, pulse widths, porches, etc the same for both or are they different?
I have a 16:9 aspect HD monitor and when I watch a 4:3 aspect program
on a digital channel, I get vertical black bars to the right and left of the
active video. E.G. The picture is centered in the screen. Does anyone
know if this is done by adjustment of the porch widths or is it done by
filling the extra 480 pixels with whatever (black seems to be the choice)?
A couple things...
1. It's not necessary (or even desirable, sometimes) for pixels to be square. You can scale the dotclock (and other parameters) and add pixels horizontally, so long as the horizontal refresh rate remains constant. I use 960x540p and 1920x540p modes that seem the same to the TV (H and V refresh rates the same); it's just that one has twice the dot clock -- and twice the pixels -- as the other. But you really shouldn't play these tricks with anything but a CRT -- if the display device has native pixels (LCD, DLP, plasma), use that resolution, even if its pixels are not square.
2. 4:3 content displayed by Myth on a 16:9 set has black bars, produced by one of three methods:
a. part of the frame, inserted by the broadcaster,
b. black area outside the active video area, inserted by MythTV, or
c. MythTV outputting a 4:3 mode; inserted by the TV.
You would use MythTV's zooming controls (w key) to manage a or b, and the set's own zooming controls to manage c. Myth will only do c if you've set it up that way.
So for your immediate question, there's no reason to generate a 1440x1080i mode; MythTV will generate the black bars itself.
nVidia cards are capable of 1080i output (or various relatives of 1080i, such as 540p). I think there's a Via card that can do it too (somebody help me out here).
-Doug
signature.asc
Description: OpenPGP digital signature
_______________________________________________ mythtv-users mailing list [email protected] http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
