Editing Scanco User Instructions (section)

====Indexed Images====
An indexed image uses direct mapping of pixel values to colormap values. Instead of intensities, a pixel value within an indexed image relates to a color value within a color lookup table. An indexed image consists of a data matrix and a colormap matrix. The data matrix can be of class uint8, uint16, or double. The colormap matrix is an m-by-3 array of class double containing floating-point values in the range [0,1]. Each row of map specifies the red, green, and blue components of a single color. Since indexed images reference color tables composed of up to 256 colors, the data values of these images are usually scaled to range from 0 to 255.