Patent ID: 8817884

Claim:
A method of encoding a video frame, the method being implemented in a video encoder, the method comprising; receiving the video frame; performing a high-pass filtering operation on the video frame to obtain a filtered video frame; resetting to zero, a value of each pixel in the filtered video frame, if the value of the corresponding pixel in the filtered video frame is less than a first threshold value, wherein the resetting forms a thresholded video frame; classifying a macro-block of the thresholded video frame into one of multiples classes on the basis of an activity measure of the macro-block, wherein the classifying further comprises determining a factor maxAct and a factor minAct, wherein maxAct equals the largest number of non-zero pixel values of any macro-block among the macro-blocks in the video frame, and wherein minAct equals the smallest number of non-zero pixel values of any macro-block among the macro-blocks in the video frame, and computing a second threshold TH 1 , wherein TH 1 is computed according to the formula: TH 1 =(maxAct−minAct)*CF+minAct, wherein CF is a control factor, wherein the classifying classifies the macro-block as a smooth macro-block if the number of non-zero pixel values in the macro-block is less than TH 1 ; and modulating a quantization scale received for quantizing the macro-block on the basis of the class of the macro-block.