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SGI file format

DescriptionThe SGI image format, also known as RGB or IRIS, is a raster graphics file format developed by Silicon Graphics, Inc. (SGI) in the 1980s. It supports uncompressed RGB and RGBA color spaces, as well as a limited form of RLE (run-length encoding) compression.
Technical detailsThe SGI format supports a variety of pixel formats, including 8-bit grayscale, 16-bit RGB, and 32-bit RGBA. It also supports various compression methods, including no compression, RLE compression, and a lossless compression method known as gzip. The header of an SGI file contains metadata such as the image width and height, the number of color channels, and the pixel format. The image data is stored in row-major order, with each row padded to a multiple of 4 bytes. In the case of RLE compression, the image data is stored in chunks of varying lengths, with each chunk consisting of a single color value followed by a count of how many times that value appears.