FourCC

A FourCC ( for eng. Four Character Code ) is a four -byte type identifier in the header area of ​​a container file or contained therein subunits ( chunks ) and specifies the format of the content. When you open a container file, the codec for decompression and display of data is selected based on this information.

A FourCC consists of four ASCII characters that indicate the mnemonic significance. Were first used in FourCCs Interchange File Format (IFF ) by Electronic Arts. According to their documentation, the idea for it comes from Apple. In Macintosh FourCCs were under the name OSType (also ResType ) used.

Unlike with file name extensions, a distinction is FourCCs between uppercase and lowercase letters. The space character is allowed to fill three characters long mnemonics, eg " AVI" for AVI files or " fmt " for the format chunk a WAVE audio file.

For RIFF formats is achieved by registering the FourCCs used in Microsoft that they are used only once. Microsoft releases to a list of registered character strings.