BMP is a standard image file format which was historically used by computers running the Windows operating system. The format is more commonly know as Bitmap files. The term bitmap was originally coined in computer programming to refer to a map of bits. Historically when you saved an image on your home PC you might have saved it as a .bhp file, this is becoming less common with .jpeg the preferred image file format with the advent of digital cameras.
Bitmap files are housed in a device-independent bitmap (DIB) format. 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. This enables Windows to show the bitmap on any type of display device - such as your monitor.
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The .pcx file extension was developed in the 1980s by the ZSoft Corporation. It has since been superseded by other image formats such as png, giff and jpeg. The file type is used rarely at present, however certain scanning devices still output to the .pcx format.
The PCX format was one of the first common bitmap image formats. A PCX file comprises of three elements: the header, image data and the 256 colour palette. PCX utiises a lossless compression technique. The compression technique used is not processor intensive which was an advantage at the time of development due to the relatively limited processing power of hardware in the 1980s.
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