A method and apparatus are disclosed for testing the accuracy of digital images
generated by a computer graphics program executed on a computer graphics system.
A test program is utilized to compare test images with a set of reference images.
Adaptive local image quantification verification aims at an image comparison that
allows specified color value and spatial shifts. The color value for each pixel
of a specified portion of the test image is compared to the average color value
of an offset array of pixels in a reference image. A test image region may be unacceptably
different from a reference image, if for any pixel of the test image region an
offset reference image array is not found that has an array size, absolute color
value difference, and spatial shift less than specified maximums.