1. A method of processing image data, said method comprising the steps of: providing a first intensity threshold value, a frame intensity threshold value, and an intensity knee; receiving a series of frames of image data, said image data comprising at least one intensity data word for each pixel of each said frame; comparing said intensity data words to said first threshold and accumulating a first number representative of the number of said intensity data words in a frame that meet an intensity criteria relative to said first threshold; and scaling a portion of said intensity data words when said first accumulated number exceeds said frame intensity threshold value.