pnmscalefixed
Scale a PNM file quickly with possibly reduced quality.
See also: pamscale.
More information: https://netpbm.sourceforge.net/doc/pnmscalefixed.html.
- Scale an image such that the result has the specified dimensions:
pnmscalefixed -width width -height height path/to/input.pnm > path/to/output.pnm
- Scale an image such that the result has the specified width, keeping the aspect ratio:
pnmscalefixed -width width path/to/input.pnm > path/to/output.pnm
- Scale an image such that its width and height is changed by the specified factors:
pnmscalefixed -xscale x_factor -yscale y_factor path/to/input.pnm > path/to/output.pnm