pnmrotate
Rotate a PNM image. tldr-pages
On several platforms
Several platforms
Rotate a PNM image by some angle (measured in degrees, counter-clockwise)
pnmrotate angle path/to/input.pnm >path/to/output.pnmIdentifySpecify the background color exposed by rotating the input image
pnmrotate -background color angle path/to/input.pnm >path/to/output.pnmIdentifyDisable anti-aliasing, improving performance but decreasing quality
pnmrotate -noantialias angle path/to/input.pnm >path/to/output.pnmIdentify