DYNAMIC BIT RATE CONTROL PROCESS

A process of bit rate control includes asymmetrical reactions to changes in the signal density of the digital video signals. In the process, two different averaging periods are employed to meet a long term bit rate target and to achieve a short term quick reaction. When encoding a motion picture, the bit rate control is relaxed during high motion scenes to allow high peaks of bit rate at those points. The coding process reacts slowly to transitions from low to high motion sequences to preserve the best overall video quality, and reacts quickly to transitions from high to low motion sequences to enhance the image quality.