US Patent 7451080 Controlling apparatus and method for bit rate

An apparatus and a method for controlling a bit rate are provided. The apparatus and method includes a buffer for storing information as to a bit rate of a frame immediately preceding a frame to be compressed, a bit rate controller for generating a target bit rate and an expected bit rate of the frame to be compressed based on the bit rate of the immediately-preceding frame and calculating a target quantization level to be applied to the frame to be compressed based on the target bit rate, with the expected bit rate and a quantization level applied to the immediately-preceding frame. The apparatus and method also includes a quantizer for performing a quantization process based on the target quantization level.