Generalised Gaussian distribution to early detect zero quantised discrete cosine transform coefficients in H.264/AVC video encoding

In H.264/AVC video encoding, zero quantised discrete cosine transform (DCT) coefficients blocks, called ZQBs, are quite common in low bit-rate video applications. The computations of DCT and quantisation can be remarkably reduced if ZQBs are detected prior to DCT and quantisation. A mathematical model is established based on analysing DCT coefficient distribution and applying the generalised Gaussian distribution theorem. Using this model, four conditions corresponding to four kinds of transform and quantisation methods are proposed. As compared with other methods in the literature, the proposed method is able to detect more ZQBs and hence reduce more computations. Experimental results show our method is superior to other methods in terms of the total number of reduced computations and usability.