SGI (image file format)
From Just Solve the File Format Problem
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(Category:Silicon Graphics) |
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− | |extensions={{ext|sgi}} | + | |extensions={{ext|sgi}}, {{ext|bw}}, {{ext|rgb}}, {{ext|rgba}} |
|pronom={{PRONOM|x-fmt/140}} | |pronom={{PRONOM|x-fmt/140}} | ||
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− | '''SGI''' is a raster image file format. The image may be uncompressed, or use | + | '''SGI''' (also known as '''IRIS''', and sometimes called '''RGB''' or '''Irix RGB''') is a raster image file format. The image may be uncompressed, or use [[Run-length encoding|RLE]] compression. |
− | [[Run-length encoding|RLE]] compression. | + | |
SGI probably stands for '''Silicon Graphics Image'''. | SGI probably stands for '''Silicon Graphics Image'''. | ||
+ | |||
+ | == Image types == | ||
+ | SGI supports the following image types: | ||
+ | * Grayscale, 8 or 16 bits/sample | ||
+ | * RGB, 8 or 16 bits/sample | ||
+ | * RGBA, 8 or 16 bits/sample | ||
+ | * RGB 3-3-2, 8 bits/pixel (obsolete) | ||
+ | * Colormapped (but no palette is stored in the file) (obsolete) | ||
+ | * Colormap (file contains only a palette; no image) (obsolete) | ||
+ | |||
+ | == Format == | ||
+ | SGI files start with a 512-byte fixed header, most of which is unused. If the image is uncompressed, the pixel data follows. Compressed images have a scanline table, followed by the compressed pixel data. | ||
+ | |||
+ | The pixel data is stored from bottom-up, instead of top-down as in most image formats. | ||
== Identification == | == Identification == | ||
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== Software == | == Software == | ||
− | * [ | + | * [[Konvertor]] |
+ | * [[Netpbm]]: pnmtosgi, sgitopnm | ||
+ | * [[ImageMagick]] (format named "SGI") | ||
+ | * [[Tom's Viewer]] | ||
* [http://svn.osgeo.org/grass/grass/branches/releasebranch_5_5/src.contrib/CERL/SGI/libimage/ libimage] | * [http://svn.osgeo.org/grass/grass/branches/releasebranch_5_5/src.contrib/CERL/SGI/libimage/ libimage] | ||
+ | |||
+ | == Sample files == | ||
+ | * [http://ftp.funet.fi/index/graphics/packages/volvis/RGB.tar.Z RGB.tar.Z] | ||
== External links == | == External links == | ||
* [[Wikipedia:Silicon Graphics Image|Wikipedia article]] | * [[Wikipedia:Silicon Graphics Image|Wikipedia article]] | ||
+ | * {{EGFF|sgiimage|SGI Image File Format File Format Summary}}, from the [[Encyclopedia of Graphics File Formats]] | ||
+ | |||
+ | [[Category:Silicon Graphics]] |
Revision as of 16:40, 28 September 2019
SGI (also known as IRIS, and sometimes called RGB or Irix RGB) is a raster image file format. The image may be uncompressed, or use RLE compression.
SGI probably stands for Silicon Graphics Image.
Contents |
Image types
SGI supports the following image types:
- Grayscale, 8 or 16 bits/sample
- RGB, 8 or 16 bits/sample
- RGBA, 8 or 16 bits/sample
- RGB 3-3-2, 8 bits/pixel (obsolete)
- Colormapped (but no palette is stored in the file) (obsolete)
- Colormap (file contains only a palette; no image) (obsolete)
Format
SGI files start with a 512-byte fixed header, most of which is unused. If the image is uncompressed, the pixel data follows. Compressed images have a scanline table, followed by the compressed pixel data.
The pixel data is stored from bottom-up, instead of top-down as in most image formats.
Identification
SGI files begin with bytes 01 DA
.
Specifications
Software
- Konvertor
- Netpbm: pnmtosgi, sgitopnm
- ImageMagick (format named "SGI")
- Tom's Viewer
- libimage