With Filestar you get 204 different skills for working productively with Portable Gray Map Image .(pgm) files.
Portable Gray Map Image
A PGM file is a grayscale image file saved in the portable gray map (PGM) format and encoded with one or two bytes (8 or 16 bits) per pixel. It contains header information and a grid of numbers that represent different shades of gray from black (0) to white (up to 65,536). PGM files are typically stored in ASCII text format, but also have a binary representation.