tldr/pages/common/pgmhist.md

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}}