1. A method for encoding a picture, comprising the steps of: (A) generating at least one respective macroblock statistic from each of a plurality of macroblocks in said picture, the at least one respective macroblock statistic being associated with characteristics of the Human Visual System (HVS); (B) generating at least one global statistic from said picture, the at least one global statistic being an average value generated by averaging the at least one respective macroblock statistic for the plurality of macroblocks over the picture; and (C) generating a respective macroblock quantization parameter for each of said macroblocks based on both (i) said at least one respective macroblock statistic and (ii) said at least one global statistic, wherein each of said respective macroblock quantization parameters comprises a respective delta quantization parameter generated only from said at least one respective macroblock statistic and said at least one global statistic.