Silicon Graphics Image (SGI) or the RGB file format is the native raster graphics file format for Silicon Graphics workstations.[3] The format was invented by Paul Haeberli.[3] It can be run-length encoded (RLE). FFmpeg and ImageMagick, among others, support this format.
Silicon Graphics Image
Filename extension |
|
Internet media type | image/sgi[1] |
Type code | '.SGI' |
Magic number | 01 DA |
Developed by | Paul Haeberli |
Initial release | 0.95 / 1995; 28 years ago[2][3] |
Latest release | 1.00 |
Type of format | image file |
Standard | SGI Image File Format[4] |
Background
Technical Details
SGI image format use big endian order. Image data scan from left to right from bottom to top.
Header
Field number | Hex offset | Length | Field name | Description |
1 | 0x00 | 2 byte | File signature/magic number | For show file is SGI file |
2 | 0x02 | 1 byte | Compression | 0 = uncompressed, 1 = RLE compressed |
3 | 0x03 | 1 byte | Bytes per pixel | 1 = 8 bit, 2 = 16 bit |
4 | 0x04 | 2 bytes | Dimension | Image dimension, equal 3 for RGBA image |
5 | 0x06 | 2 bytes | X size | Image width |
6 | 0x08 | 2 bytes | Y size | Image height |
7 | 0x0A | 2 bytes | Number of channels | Number channel in image, equal 4 for RGBA image |
8 | 0x0C | 4 bytes | Minimum pixel value | Smallest pixel value in image |
9 | 0x10 | 4 bytes | Maximum pixel value | Largest pixel value in image |
10 | 0x14 | 4 bytes | Reserved | No use, ignore |
11 | 0x18 | 80 bytes | Image name | C string name have last byte equal 0x00 |
12 | 0x68 | 4 bytes | Color map ID | Only for color map image |
13 | 0x6C | 404 bytes | Dummy | For make head 512 bytes long. Ignore |
File Signature/Magic Number
See also
- SGI IRIS
References
- ^ .sgi MIME type not registered at IANA
- ^ Paul Haeberli (1996). "The SGI Image File Format 0.97". Silicon Graphics. Retrieved 2014-03-07.[dead link] Alt URL
- ^ Jump up to:a b c James D. Murray, William van Ryper (April 1996). "SGI Image File Format File Format Summary". Encyclopedia of Graphics File Formats, Second Edition. O'Reilly. ISBN 1-56592-161-5. Retrieved 2014-03-07.
- ^ Paul Haeberli (1996). "The SGI Image File Format 1.00". Silicon Graphics. Retrieved 2014-03-07.
- ^ Lars Haglund (Feb 2006). "The SVT High Definition Multi Format Test Set" (PDF). SVT. Retrieved 2014-02-23.
- ^ "SVT_MultiFormat/2160p50_CgrLevels_Master_SVTdec05". Video Quality Experts Group (VQEG). 2006. Retrieved 2014-03-01.
- ^ Marta Mrak, Mislav Grgic, Murat Kunt (2010). High-Quality Visual Experience: Creation, Processing and Interactivity of High-Resolution and High-Dimensional Video Signals. Signals and Communication Technology. Springer. pp. 147–154. ISBN 978-3-642-12802-8. LCCN 2010925849.
