ImageGear for Java
RAS
| ImageGear for Java User Guide > ImageGear Imaging Formats Reference > ImageGear Supported File Formats Reference > RAS |
| Full Name | RAS (Sun Raster Data Format) |
| Format ID | ImGearFormats.RAS |
| File Extension(s) | *.ras |
| Data Type | Raster Image |
| Data Encoding | Binary |
| IG Multipage Support | No |
| IG Alpha Channel Support | No |
| IG Platforms Support | WIN32, WIN64, Linux32, Linux64, MAC32, MAC64 |
N/A
None
Bitmap images used under the SunOS system and UNIX imaging applications are usually stored in Sun Raster form.
The Sun Raster header contains image data (size and type), and the type and size of the colormap, if present. It also contains a Sun Raster identifying tag called "MagicNumber," which always contains the same value. A type field identifies the version of Sun Raster, the most common are called "Old" and "Standard". These are actually the same format and indicate that the image is not compressed. Other possible versions of Sun Raster files include TIFF and IFF, meaning that the image data was converted from one of these formats.
Following the header is a colormap, if applicable. Most 24 or 32-bit raster images do not use a colormap, but rather store the color values directly with the image data. This is known as "truecolor".
The last element of the Sun Raster file is the image data itself. It is usually in 2D raster format.
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.