ImageGear .NET v25.0 - Updated
IFF
User Guide > File Formats and Compressions > File Formats > File Formats Reference > IFF
Full Name Interchange File Format
Format ID ImGearFormats.IFF
File Extension(s) *.iff
Data Type Raster Image
Data Encoding Binary
Multi-Page Support Yes
Alpha Channel Support No
Metadata Update Support No
ImageGear Platforms Support WIN32, WIN64, Unix, Unix64, .NET, .NET64, MAC

ImageGear Supported Versions

ImageGear Supported Features

ImageGear Read Support

ImageGear Write Support

ImageGear Filter Control Parameters

None

Comments

This type of file format is referred to as a "wrapper" because it can include any type of data that is encoded in any manner.

The basic organization of the IFF file format utilizes storage structures known as "chunks". A chunk is a block of data that contains its own header (that identifies the chunk size and type). This makes it easy for an IFF viewer to identify chunks and to skip over the ones that are not necessary.

The Header Chunk contains 17 fields, including the size of the header chunk, the identification of the chunk as a header, the size and origin of the image, data encoding (yes or no), and aspect ratio.

A "CMG Chunk" may follow, containing data specific to Amiga display hardware.

A "CMAP Chunk" contains the RGB palette for the image.

The "Body Chunk" (also called the ILBM or "interleaved bitmap"), is the image data itself. It is stored in an "interleaved" format, by bit plane. Interleaving allows for data with different resolutions to be neatly stored together. The data may be uncompressed or compressed using an RLE scheme. See See RLE Compression. section at the beginning of this chapter for more information.

References Used

Brown, C. Wayne, and Barry J. Shepherd. Graphics File Formats: Reference and Guide. Greenwich, CT.: Manning Publications, 1992.

Kay, David C. and John R. Levine. Graphics File Formats. Windcrest Books, 1992.

Murray, James D. and William vanRyper. Encyclopedia of Graphics File Formats. Sebastopol, CA: O'Reilly & Associates, Inc., 1994.