A Fuzzy Bit Allocation Algorithm for Variable Bit Rate Video Coding

A fuzzy bit allocation method, applicable to many rate control algorithms targeted for variable rate video applications, is proposed in this paper. In low-delay video communication applications, a constant short-term average bit rate is required. However, in variable bit rate applications, such as streaming and broadcast applications, a constant long-term average bit rate is sufficient and a higher short-term variation in bit rate is acceptable. A variable bit rate video can provide better visual quality and coding efficiency in comparison with a constant bit rate video. The proposed fuzzy bit allocation algorithm is employed for encoding special P frames. To take advantage of variable bit rate video, the proposed method is implemented independently of the rate control algorithm. Two fuzzy systems are used to determine the location and the quantization parameter of special P frames. The proposed method is implemented on a JM H.264/AVC video encoder. Experimental results show that it can improve the quality of compressed video while having a low degree of computational complexity.