Patent ID: 7688338

Claim:
In a display system, an inputted video sequence comprising N image frames to be displayed which each consists of T pixels, each pixel of each image frame comprising M color components and M gray scale levels which each corresponds to one of the M color components, N, T, and M being a natural number, respectively, an apparatus functioning adjusting the M gray scale levels of the M color components of the ith image frame in the video sequence, i being an integer index ranging from 1 to N, the gray scale levels of the image frames previous to the ith image frame having been adjusted, each of the image frames previous to the ith image frame having a respective brightness ratio which relates to the gray scale levels been determined of said one image frame and is within an allowable range, a plurality of gains which each corresponds to one of the brightness ratios varying within the allowable range being previously provided, said apparatus comprising: a first calculating module for retrieving all of the gray scale levels of all pixels of the ith image frame, and calculating, according to all of the gray scale levels of all pixels of the ith image frame, a current brightness ratio; a second calculating module for calculating, according to all of the brightness ratios of the image frames previous to the ith image frame and the current brightness ratio, an averaged brightness ratio; a judging module for receiving the current brightness ratio and the averaged brightness ratio, and judging whether the difference between the current brightness ratio and the averaged brightness ratio is larger than a threshold, and then the judging module outputting one selected from the current brightness ratio or the averaged brightness ratio as an outputted brightness ratio according to the judging result of the judging module, wherein the outputted brightness ratio is also within the allowable range; a determining module for storing the brightness ratios varying within the allowable range and the corresponding gains, the determining module having an input coupled to receive the outputted brightness ratio, the determining module also functioning determining the gain corresponding to the outputted brightness ratio; and an adjusting module for receiving the gain corresponding to the outputted brightness ratio, and multiplying the gray scale level of each color component of the ith image frame by the gain corresponding to the outputted brightness ratio, respectively.