These are the pictures displayed during the licensing screen.
MR images are small image files that can be inserted into the liscensing screen of a home-made Dreamcast disc. Specifically, they are inserted into the IP.BIN bootfile in a layout destined to be a Dreamcast disc. The maximum dimensions are 320x90, and the background color is #C3C3C3. The image must be converted from a BMP or PNG file to an MR file, then inserted into the IP.BIN. Converters and insertion tools are listed below.
MR Image insertion programs