792 x 576 pixel mode

If you have an Xbox with the Focus FS454 video encoder and use PAL output, you can follow the procedure described here to set it up for overscanned 792x576 resolution, which looks much nicer than the default 640x480. PAL video is usually captured in the resolution 720x576, so the picture lines are not scaled at all in the vertical direction if a frame height of 576 pixels is used. And in the horizontal direction the pixels are fuzzy anyway (since the signal is analog), so the horizontal downscaling is not very noticeable. A completely unscaled 720x576 mode could have been used instead, but the software becomes less messy if the pixels are square, so 720x576 is only used when actually playing video.

To calculate the number of horizontal pixels needed for a square-pixel frame, use the fact that 702 of the 720 pixels represent 4/3 of the frame height: for square pixels this means that (720/702)*(4/3)*576 = 787.6923 horizontal pixels are needed. This is rounded up to the nearest multiple of 8 (because of hardware requirements) which is 792.

Non-square pixels are rather tricky beasts. If you want to learn more about this subject, I recommend this excellent web page: A Quick Guide to Digital Video Resolution and Aspect Ratio Conversions.

Here is the procedure for setting up the 792x576 mode: