pgmtoppm
Colorize a PGM image. tldr-pages
On several platforms
Several platforms
Map all greyscale values of the input image to all colors between the two specified colors
pgmtoppm -black red -white blue path/to/input.pgm >path/to/output.ppmIdentifyMap all greyscale values of the input image to colors according to the specified colormap
pgmtoppm -map path/to/colormap.ppm path/to/input.pgm >path/to/output.ppmIdentify