Type: 
    Extension:
      Version: 
  Compression:
  Color Depth:
   Maintainer: 
Specification:

The Portable greymap file format is part of the Extended Portable Bitmap
Utilities (PBMPLUS). PGM is used as an intermediate format for storing
greyscale bitmap information generated by the PBMPLUS toolkit. PGM files may
be either binary or ASCII and store pixel values up to 8 bits in size.

Information and source code for PGM can be found in the distribution for
PBMPLUS (see the section on the PBM format for information on PBMPLUS). The
specification for the PGM format can also be found in the manual page for
pgm(5) on many Unix systems.