A Linear Rate Estimation Model Based on Syntax Elements in AVS2

CABAC is an entropy coding in AVS2, which brings higher performance for coding. Because in the rate distortion optimization, we need to calculate every coding mode to get the number of bits encoded by entropy coding, and then we determine the optimal coding mode by comparing the distortion and rate between different modes. This process increases the complexity of the computation and prolongs the time of the coding. In order to reduce the complexity of rate distortion and optimize computation, this paper proposes a method based on syntax elements to estimates bit rate, which uses bit rate estimation instead of actual rate. The experimental results show that the average performance of high definition video (1080P) is reduced by 2.2% and the average coding time is 30.87%.