Patent ID: 7133448
Filing Date: 2006-11-07
Classification: H04N

Abstract:
1. A method for rate control in moving picture video compression comprising the steps of: calculating a total activity measure for a current picture to be encoded in a set of consecutive pictures of a video sequence; estimating a complexity measure of the current picture based on the total activity measure of the current picture and an activity-to-complexity ratio of a previously encoded picture of the same type in the set of consecutive pictures; updating an instantaneous complexity measure for the set of consecutive pictures with the estimated complexity measure of the current picture; allocating a target bit budget to the current picture depending on the estimated complexity measure and the instantaneous complexity measure, wherein the allocated target bit budget is inversely proportional to the instantaneous complexity measure; encoding the current picture in the video sequence based on the target bit budget; and after encoding the current picture, computing the activity-to-complexity ratio for the current picture based on the total activity measure, actual bits consumed by the current picture and the average quantization step size of the current picture; wherein the activity-to-complexity ratio of the current picture varies directly with the total activity measure and inversely with the actual consumed bits and the average quantization step size of the current picture.