ppmhist

Print a histogram of the colors present in a PPM image. See also: pgmhist. More information: https://netpbm.sourceforge.net/doc/ppmhist.html.

• Generate the histogram for human reading:

ppmhist -nomap path/to/image.ppm

• Generate a PPM file of the colormap for the image, with the color histogram as comments:

ppmhist -map path/to/image.ppm

• Display version:

ppmhist -version