Flip or rotate a PAM or PNM image. More information: https://netpbm.sourceforge.net/doc/pamflip.html.
pamflip {{[-r|-rotate]}}{{90|180|270}} {{path/to/input.pam}} > {{path/to/output.pam}}
pamflip {{[-lr|-leftright]}} {{path/to/input.pam}} > {{path/to/output.pam}}
pamflip {{[-tb|-topbottom]}} {{path/to/input.pam}} > {{path/to/output.pam}}
pamflip {{[-xy|-transpose]}} {{path/to/input.pam}} > {{path/to/output.pam}}