| Extension | .pnm |
| Category | images |
| Description | The Portable Any Map (PNM) format is a collection of image file formats designed for portable images. Each image essentially represents a pixel value map that can encode data in grayscale or color. There are three main types of files in the PNM format family: Portable BitMap (PBM), Portable GrayMap (PGM), and Portable PixMap (PPM). |
| Technical details | PBM format uses binary pixel data. Each pixel is represented by a single bit, where 0 indicates black and 1 represents white. The pixel data for each row is organized as a bit sequence, padded to a full byte. Conversely, the PGM format handles grayscale pixel data. It represents each pixel with a single byte. The pixel data is arranged in rows, with each row of pixel data grouped together. PPM format deals with color pixel data. Each pixel is represented by three bytes, each indicating the red, green, and blue components of a color. This pixel data is also organized in rows, with each row grouped together and represented by sets of three bytes. Finally, note that PNM files can be easily converted between these three formats. Furthermore, specific software tools can convert PNM files to other image file formats, and vice versa. |
