Improving the Discrete Cosine Transform by the Sign Symbol Feature in H.265/HEVC

DCT compression is widely used in H.265/HEVC for the video coding processing. This paper deals with enhancing the compression ratio by improving the Discrete Cosine Transform (DCT) by taking into account the sign-symbol (result after standard DCT transform); this is done by evaluating the derivative of sample data to determine the DCT matrix improvement. It is shown that our proposed can be embedded into standard DCT coefficients and is compatible with the feature in the video coding. Experiments show that the proposed method gives an improvement in computing requirements and can achieve a reasonable compromise between coding quality and efficiency. It offers no divergence from the H.265/HEVC standards and can be used in current systems.