Patent ID: 6937653

Claim:
A rate control apparatus for real-time video communication, the rate control apparatus comprising: an initialization means for setting an initial value required for rate control according to a transmission speed and the number of input frames; a target bit calculation means for obtaining the target number of encoding bits, maximum allowable number of bits, and minimum allowable number of bits in consideration of a buffer state and a transmission speed; a rate control and encoder means for executing rate control and encoding using the maximum allowable number of bits and the minimum allowable number of bits; a stuffing control means for comparing the size of a bit stream from the rate control and encoding means with the target number of encoding bits from the target bit calculation means for thereby outputting stuffing bits; a buffering means for storing a combination of the bit stream from the rate control encoding means and the stuffing bits from the stuffing control means for thereby outputting them to the target bit calculation means; a frame skip means for outputting a frame skip signal according to the buffer occupied state signal from the buffering means; and a control logic means for controlling an encoding process of each of the above elements and determining whether or not the next input frame is encoded according to the frame skip signal from the frame skip means, wherein the rate control and encoder means controls such that the length of a bit stream does not exceed the maximum allowable number of bits by not encoding picture information, in a case that the total number of encoding bits of the bit stream accumulated until the currently encoded macro-block is reached.