pgmhist — Print a histogram of the values present in a PGM image. See also: `ppmhist`. More information: <http

Display the histogram for human reading

pgmhist {{path/to/image.pgm}}

Display the median grey value

pgmhist {{[-me|-median]}} {{path/to/image.pgm}}

Display four quartile grey value

pgmhist {{[-qua|-quartile]}} {{path/to/image.pgm}}

Report the existence of invalid grey values

pgmhist {{[-f|-forensic]}} {{path/to/image.pgm}}

Display machine-readable output

pgmhist {{[-ma|-machine]}} {{path/to/image.pgm}}