An analysis of the DCT coefficient distribution with the H.264 video coder

By extensive analysis with several video sequences, we observed that the statistical distribution of the DCT coefficients in typical video coding applications is closer to a Cauchy distribution than to a Laplacian distribution. We developed the rate and the distortion expressions as a function of the video coder quantization parameter based on this observation. Experiments with an H.264 codec demonstrate that the Cauchy distribution based expressions provide better estimates for the actual rate and distortion than those that are based on the Laplacian distribution.