Early detection of all-zero coefficients in H.264 based on DCT coefficients distribution

Based on the discrete cosine transform (DCT) coefficients distribution, an effective method of early detecting all-zero discrete cosine coefficients blocks in H.264 is proposed. A mathematic model is established based on Laplacian distribution of DCT coefficients and a criterion under which each quantized coefficient becomes zero is derived. The simulation results show that compared to the Xie's method built on Gaussian distribution, the proposed method reduces encoding time averagely without video-quality degradation for low or middle bit-rate video sequences.