This describes the bitmap graphics-file formats used by the Microsoft Windows operating system V3.x, Window 95 and OS/2.
Windows bitmap files are stored in a device-independent bitmap (DIB) format that allows Windows to display the bitmap on any type of display device. The term "device independent" means that the bitmap specifies pixel color in a form independent of the method used by a display to represent color. The default filename extension of a Windows DIB file is .BMP.
Windows versions 3.0 and later support run-length encoded (RLE) formats for compressing bitmaps that use 4 bits per pixel and 8 bits per pixel.
Compression of 8-Bits-per-Pixel Bitmaps the DIB is compressed using a run-length encoded format for a 256-color bitmap. This format uses two modes: encoded mode and absolute mode. Both modes can occur anywhere throughout a single bitmap.
Compression of 4-Bits-per-Pixel Bitmaps the DIB is compressed using a run-length encoded format for a 16-color bitmap. This format uses two modes: encoded mode and absolute mode. These are different than the 8bit methods.
Macintosh File Type of: BMPp or BINA
MS-DOS extension: .BMP