BACKLIGHT CONTROL AND DISPLAY MAPPING FOR HIGH DYNAMIC RANGE IMAGES

摘要

Systems and methods are disclosed for dynamically adjusting the backlight of a display during video playback. Given an input video stream and associated minimum, average, or maximum luminance values of the video frames in the video stream, values of a function of the frame min, mid, or max luminance values are filtered using a temporal filter (320) to generate a filtered output value for each frame. The instantaneous dynamic range of a target display is determined (330) based on the filtered output value and the minimum and maximum brightness values of the display. A backlight control level is computed based on the instantaneous dynamic range, and the input signal is tone mapped by a display management process to be displayed on the target display at the selected backlight level. The design of a temporal filter based on an exponential moving average filter and scene-change detection is presented.