---
syntax: markdown
tags: [tldr, common]
source: https://github.com/tldr-pages/tldr.git
---
# 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}}`
