ppmtobmp
Convert a PPM image to a BMP file.
TLDR
Convert a PPM image to a BMP file
$ ppmtobmp [path/to/file.ppm] > [path/to/file.bmp]
Explicitly specify whether or not a Windows BMP file or an OS/2 BMP file should be created
$ ppmtobmp -[windows|os2] [path/to/file.ppm] > [path/to/file.bmp]
Specify the number of bits to use for each pixel
$ ppmtobmp -bbp [1|4|8|24] [path/to/file.ppm] > [path/to/file.bmp]