The Resource Interchange File Format (RIFF) is a generic meta-format for storing data in tagged chunks. It was introduced in 1991 by Microsoft and International Business Machines. It is a clone of Electronic Arts s Interchange File Format, introduced in 1985, the only difference being that multi-byte integers are in little-endian format, native to the 80x86 processor series used in IBM PCs, rather than the big-endian format native to the 68k processor series used in Amiga and Apple Macintosh computers, where IFF files were heavily used.
The Microsoft implementation is mostly known through file formats like AVI and WAV, which both use the RIFF meta-format as their basis.
RIFF files consist of a simple header followed by chunks . The format is identical to IFF, except for the endianness as previously stated.
Header
4 bytes: The ASCII identifier RIFF .
4 bytes: an unsigned, little-endian 32-bit integer with the length of the overall file (except this field itself and the RIFF identifier).
4 bytes: An ASCII identifer for this particular filetype, such as AVI or WAVE .
Chunks follow from here on. Each chunk consists of
4 bytes: An ASCII identifier for this chunk, e.g. fmt or data
4 bytes: an unsigned, little-endian 32-bit integer with the length of this chunk (except this field itself and the chunk identifier).
Variable-sized field: the chunk data itself, of the size given in the previous field.
A pad byte, if the chunk s length is not even.
More information about the format can be found in the Interchange File Format article.
= See also =
Interchange_File_Format
AIFF
FourCC
=External links=
[http://msdn.microsoft.com/library/default.aspurl=/library/en-us/multimed/htm/_win32_resource_interchange_file_format_services.asp Resource Interchange File Format Services]
[http://msdn.microsoft.com/archive/default.aspurl=/archive/en-us/dx81_c/directx_cpp/htm/avirifffilereference.asp RIFF AVI file reference]
[http://msdn.microsoft.com/archive/default.aspurl=/archive/en-us/dx81_vb/directx_vb/htm/_dx_reading_wave_files_dxaudio.asp Reading WAVE files]
[http://msdn.microsoft.com/library/default.aspurl=/library/en-us/DMusicC/htm/directmusicfileformat.asp DirectMusic file format]
[http://support.microsoft.com/default.aspxscid=KB;EN-US;Q120253 Multimedia Registration Kit]