In videoconference system

the key portion is bit rate control method

because it affects coded image quality directly.In this paper

buffer pure occupancy control algorithm is analysed and its parameter is designed starting from the principle of buffer smoothing fluctuant bit current.For its coded image quality is not good enough in buffer occupancy control algorithm

studies the buffer occupancy perceptual regulation algorithm and the bit allocation based buffer capacity control algorithm.After all

three bit rate control algorithm is compared and testified.