Star Trek 25th PRI
Files possessing the suffix .pri contain the priority maps for rooms. They have been saved with a granularity of 2x1.
 Format Specifications
PRI files do not contain any header information. Instead, they are a sequence of 32000 byte values that describe the priority map (i. e. the depth information of a room). Each byte represents a 2x1 pixel large area of the screen, starting from the top left to the bottom right line-wise.