rgb3toppm

Combine three PGM images into one PPM image. See also: ppmtorgb3. More information: https://netpbm.sourceforge.net/doc/rgb3toppm.html.

• Combine three PGM images (representing red, green and blue color components) into one PPM image:

rgb3toppm path/to/red_file.ppm path/to/green_file.ppm path/to/blue_file.ppm > path/to/output.ppm