Gets the properties of DIB data in an external image.
graphics-ports
analyze-external-image external-image => width height color-table number
external-image
An external-image.
width
An integer.
height
color-table
A color table.
number
The analyze-external-image function returns the width, height, color-table, and number of important colors for the external image external-image .
analyze-external-image
The image data in external-image must be in Device Independent Bitmap (DIB) format.