What is a PNM File?
A PNM file stores a bitmap image using either binary data or plain ASCII text. It was designed to store different types of portable colors, grayscale, and monochrome images. Optionally, a PNM file may also contain raster graphic data in .PBM, .PGM, or .PPM format. .PNM files only have a single image file inside them and do not use any compression algorithm.
Download PNM Sample Files
You can download and use .PNM files from below that are available in different sizes.