1. A method of a digital processor for determining a region-based weighted prediction with improved global brightness detection, the method comprising: applying a global brightness change detection method by computing the weighted prediction parameters; determining if the brightness change is a different amount of change for the different regions; if the change is not different, calculate motion estimation and setting reference index to 1 and setting reference index to zero when there is change; determining the best motion vector, motion vector cost and the best reference input; and determining a region-based weighted prediction with improved global brightness detection based on the motion vector data.