PCX (PC Paintbrush) Image Format

Format name: PC Paintbrush file format
File extension: .pcx

PCX (abbreviation from "Personal Computer eXchange") was the first standard bitmap image format for the IBM PC. It was initially used in PC Paintbrush, an application developed by ZSoft Corporation. In the early '80s, Microsoft licensed PCX and PC Paintbrush from ZSoft. Later PC Paintbrush was renamed Windows Paintbrush and bundled with Windows. Nowadays, P.C.X. is losing its popularity, but P.C.X. files (which can be easily recognized by the .pcx extension) are still in use in some areas.

A P.C.X. file consists of three sections: a P.C.X. header, bitmap array data, and an optional color table. The 128-byte P.C.X. header contains a few fields, including ones for the image size and for the number of bits used to encode the information about each pixel's color. Bitmap array data is compressed using the simple RLE algorithm. The optional color table in the end of the file contains 256 RGB values that define colors in the image. The P.C.X. format was originally developed for CGA and EGA graphics cards but later was modified for VGA and full-color graphics cards. Nowadays, P.C.X. format files can have an image depth of 1, 4, 8, or 24 bits.