BMP Image

The BMP file format, also known as bitmap image file, DIB (Device Independent Bitmap) file format, and bitmap, is a raster graphics image file format used to store bitmap digital images, independent of the display device (such as a graphics adapter), particularly on Microsoft Windows and OS/2 operating systems.

The BMP file format is capable of storing two-dimensional digital images in both monochrome and colour, in various colour depths, and optionally with data compression, alpha channels and colour profiles. The Windows Metafile (WMF) specification covers the BMP file format.

Many older graphical user interfaces used bitmaps in their embedded graphics subsystems; for example, the GDI subsystem of the Microsoft Windows and OS/2 platforms, where the specific format used is the Windows and OS/2 bitmap file format, usually named with the extension .BMP.

While most BMP files have a relatively large file size due to the lack of any compression (or generally low run-length ratio encoding on palletised images), many BMP files can be significantly compressed with lossless data compression algorithms such as ZIP because they contain redundant data. Some formats, such as RAR, even include routines specifically aimed at efficient compression of such data.