sgitopnm(1) convert a SGI image file to a portable anymap


sgitopnm [-verbose] [-channel c] [SGIfile]


Reads an SGI image file as input. Produces a PGM image for a 2-dimensional (1 channel) input file, and a PPM image for a 3-dimensional (3 or more channels) input file.

Alternatively, produces a PGM image of any one of the channels in the input file.


Give some information about the SGI image file.
-channel c
Extract channel c of the image as a PGM image. Without this option, sgitopnm extracts the first 3 channels as a PPM image or, if the input has only 1 channel, extracts that as a PGM image, and if the input has 2 channels, fails.


SGI Image File Format documentation (draft v0.95) by Paul Haeberli ([email protected]). Available via ftp at


Copyright (C) 1994 by Ingo Wilken ([email protected])