Contrast Enhancement Using Local Area Brightness and Gain Control

Abstract

Because of the limited dynamic range of most display devices, potentially available sensor information may not be optimally displayed for use by an operator. Generally, some portions of a scene will be dark while others will be very bright, and it is often difficult to obtain an acceptable value of video gain. A gain setting which provides good contrast in the darker portions of the image results in saturation of the display and a loss of detail in the light portions of the scene. Local Area Brightness and Gain Control (LABGC) is an image processing algorithm designed to increase contrast in local areas of the display without causing saturation in other areas, thereby providing greater displayed detail. It is a contrast enhancement technique that automatically adjusts display brightness and gain in an effort to retain the maximum sensor video dynamic range while operating within the constraints of a limited dynamic range display device.