| Full Name | Xerox 9700 graphic image (IMG) |
| Format ID | IG_FORMAT_XRX = 46 |
| File Extension(s) | *.img |
| Data Type | Raster Image |
| Data Encoding | Binary |
| Color Profile Support | No |
| Multi-Page Support | No |
| Alpha Channel Support | No |
Version 1.0
Version 2.0
None
None
The IMG header contains the width, height and resolution of the image. Following the header is compressed data. The sample values of a binary image are compressed and then encoded into a sequence of bits. Compression is achieved by predicting a pixel value based on pixel values that have already been computed. For example, the predicted value of a pixel may be that of the corresponding pixel on the previous scan line. Up to fifteen different compression techniques are used, each designed to remove redundancy from a certain kind of image - text characters, line art, and halftones of various screen frequencies. The algorithm adapts to the properties of the image by selecting the technique that will perform the best.
Xerox System Integration Standard. Raster Encoding Standard. Xerox, XNSS 178506, June 1990.