View Single Post
Old 12-27-05, 01:28 PM   #4
_john_i_
gtx260/8200M G/DIY Linux
 
Join Date: Aug 2004
Location: Austin, TX USA
Posts: 137
Default Re: Can we use virtual screen sizes to compensate for overscanning?

I've been battling the same thing here. I wish there was a way to make a subscreen. I tried running an Xnest window at the correct coordinates, but you lose nvidia glx and xv in the Xnest.

To compensate for this when watching movies with mplayer, through trial and error I have found a way set the "expand" video filter to shrink and position the movie properly so I don't lose anything to the overscan.

On my TV, I can multiply the width and hight by 0.097 to shrink the movie down to the right size. To shift it to the correct position I found I can multiply the width by 0.07 and the height by 0.04

So for a movie that is 680 x 382 pixels, I would derive the shrink parameters as: 680 * 0.097 = 65, 382 * 0.097 = 37, 680 * 0.07 = 47, 382 * 0.04 = 15

So on mplayer:

mplayer -vf expand=-65:-37:47:15 movie.avi

Note the first two numbers should be negative because we are shrinking it down by that many pixels. The third and fourth parameters shift it down and to the right.

I'm sure this formula will be different for your TV. If you are not using mplayer, I'm not sure how to accomplish this. It took a lot of trial and error to find the magic numbers.

I would really prefer a way to make X fit the proper position so I wouldn't have to do this.
_john_i_ is offline   Reply With Quote