Towards real-time hardware gamma correction for dynamic contrast enhancement

Abstract

Making the transition between digital video imagery acquired by a focal plane array and imagery useful to a human operator is not a simple process. The focal plane array “sees” the world in a fundamentally different way than the human eye. Gamma correction has been historically used to help bridge the gap. The gamma correction process is a non-linear mapping of intensity from input to output where the parameter gamma can be adjusted to improve the imagery's visual appeal. In analog video systems, gamma correction is performed with analog circuitry and is adjusted manually. With a digital video stream, gamma correction can be provided using mathematical operations in a digital circuit. In addition to manual control, gamma correction can also be automatically adjusted to compensate for changes in the scene.