CmdID / Commands
pnmtoddif
Convert a PNM image to a DDIF image file. tldr-pages
On several platforms
Convert a PNM image to a DDIF image file
pnmtoddif path/to/image.pnm >path/to/image.ddifIdentify
Explicitly specify the horizontal and vertical resolution of the output image
pnmtoddif -resolution horizontal_dpi vertical_dpi path/to/image.pnm >path/to/image.ddifIdentify