pamscale

Scale a Netpbm image. More information: https://netpbm.sourceforge.net/doc/pamscale.html.

pamscale -width width -height height path/to/input.pam > path/to/output.pam

pamscale -width width path/to/input.pam > path/to/output.pam

pamscale -xscale x_factor -yscale y_factor path/to/input.pam > path/to/output.pam

pamscale -xyfit bbox_width bbox_height path/to/input.pam > path/to/output.pam

pamscale -xyfill box_width box_height path/to/input.pam > path/to/output.pam