Menu still picture

I create a menu with a still picture (*.jpg) in DVD maestro and in the editor mode for create button the picture is good but when I compile and test my DVD the picture quality is very bad. Have you got an idea to explain why, and what I can do?

Are you using a picture with the same resolution as your video, or are you using a low-res image? e.g.: PAL = 720x576; NTSC = 720x480 Arky ;o)

I use 720*576 picture(PAL). The quality concern the contrast and the luminosity of the picture. My video are encoded with tmpgenc and is good but the still picture encoded with dvdmaestro are not.

use a bmp instead of a jpg. Enf...