REAL TIME DYNAMIC RANGE COMPRESSION FOR IMAGE ENHANCEMENT

Circuitry is disclosed which generates signals which may be applied to subsequent processing circuitry, such as a display device. Applied signals having a first predetermined number of intensity levels are transformed by the circuitry into signals having a smaller predetermined number of intensity levels suitable for application to the display device. A histogram representing the number of occurrences of each particular intensity level in the first predetermined set of intensity levels is generated. This histogram is analyzed, and a plurality of peak intensity levels are selected for application to the display device. Mapping signals are generated which are determinative of which subsets of the remaining intensity levels are mapped into particular ones of the selected peak intensity levels. The mapping signals are then utilized to transform applied signals received during a subsequent time period into signals having the selected peak intensity levels. Output signals are provided having the selected peak intensity levels to the display device. The circuitry preserves the gross statistics of the image scene by selecting the dominently populated intensity levels for display.