An efficient method for early detecting all-zero quantized DCT coeffcients for H.264/AVC

The residual signal gained after motion estimation needs to be transformed and quantized prior to entropy coding in H.264/AVC. In many cases, especially in low bitrate situation, the probability that obtain all zero quantized coefficients block (AZB) is high. In this paper, we study the characteristics of 4×4 integer transform first, and then we use the divide and rule strategy to inverse the formulae of integer transform and quantization. By this way, we get a new sufficient condition for AZB detection. The experiment results show that our algorithm can find out more AZBs compared with existing methods without any loss and save more computations at the same time.