Abstract: Plateau Equalization (PE), automatically optimizes, tracks changes in luminance, and adjusts in real time the display of wide dynamic range imagery from infrared cameras. The PE approach includes an automated contrast control system which uses an infrared camera, a microprocessor, and an 8 bit monitor to display the IR scenes with automatic control of the contrast of the IR data. This system allows 8 bit monitors to be used with 12 bit cameras. The camera acquires IR data which is digitized for the microprocessor. The microprocessor processes the IR data with a plateau equalization program to output digital IR data for the monitor with controlled contrast. The monitor displays the output of the microprocessor. Plateau Equalization occurs as peaks in infrared data are cut off into an assigned plateau value so that the display allocation emphasizes smaller features of interest in the scene and remains immune to flicker noise.

Abstract: A histogram projection system which automatically optimizes, tracks changes in luminance and adjusts in real time the display of wide dynamic range imagery from IR cameras. It is computationally simpler than and offers markedly superior results to the standard available technique for this purpose, histogram equalization. The new technique assigns display dynamic range equally to each occupied intensity level in the raw data in contrast to the old procedure which assigns dynamic range in proportion to the number of pixels at given levels. Less shot noise and greater resolution of image detail for smaller objects or targets are the main improvements from the new algorithm. By the expedient of undersampling the image pixels in carrying out the histogram processing, one can in effect gradually increase the degree of dynamic range assigned to majority or background pixel levels, thereby enhancing the contrast in background regions when desired.