pgmhist

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

• Display the histogram for human reading:

pgmhist path/to/image.pgm

• Display the median grey value:

pgmhist -median path/to/image.pgm

• Display four quartile grey value:

pgmhist -quartile path/to/image.pgm

• Report the existence of invalid grey values:

pgmhist -forensic path/to/image.pgm

• Display machine-readable output:

pgmhist -machine path/to/image.pgm