v.sum v.sum finds the sum of all the brightnesses in the image, and reports the sum as a single int. v.sum finds the sum of all the brightnesses in the image, and reports the sum as a single int. All streams are translated to int8 before processing. Brightness values less than the noise threshold are ignored. Usually v.sum will be used to sum the results of an object like v.motion or v.presence or v.edges, when these objects are not in signed mode. Since in this case, most pixels will be zero, the sum is a useful measure of total motion, total presence or overall edginess.

from the library : softVNS Format : External Environment : jitter / max commercial Max 4.x http://homepage.mac.com/davidrokeby/softVNS.html