Chroma equalization method for video coding

Abstract

The present invention relates to a chromatic degree equalization method and a chromatic degree quantification parameter correcting method used for the video frequency coding. The equalization method comprises: the method obtains the brightness component residual error SADY and chromatic degree component residual error SADY between the present image and the advancedly measured image; after obtaining the brightness component residual error SADY and chromatic degree component residual error SADY, the residual error SATDY and SATDC in the frequency field is got through calculation; on basis of the residual error SADY, SATDC and brightness quantification parameter QPY and the correcting chromatic degree quantification parameter QPC, the coding is held respectively on basis of the brightness component and the chromatic degree component from the brightness quantification parameter QPY and the chromatic degree quantification parameter QPC. Through the method, using the present image brightness and the chromatic degree component residual error and the comparison of the distribution, adjusting the chromatic degree quantification parameter, and controlling the compress ratio of the chromatic degree component, thereby balancing the peak value SNR for the chromatic degree component and the brightness component, further balancing the renewing quality and saving code rate.

Description

【Technical field】 [0001] The invention relates to a video encoding method, in particular to a chroma equalization method and a chroma quantization parameter correction method for video encoding. 【Background technique】 [0002] In the case of video real-time communication, the sampling format of the video signal is usually Y:U:V=4:2:0, and the Baseline Profile (basic grade) of the digital video coding standard H.264 also only supports Y:U:V=4: 2:0 format. As shown in FIG. 1 , under this sampling format, every four sampling points of the luminance component (Y) corresponds to one sampling point of the chrominance components (U, V) on average. The reason for adopting this sampling format is to use the characteristics of human vision, that is, the sensitivity to luminance components is greater than that to chrominance components. [0003] The difference in the spatial sampling rate between the luma component and the chrominance component determines their difference in image co...

AI Technical Summary

Problems solved by technology

[0005] In order to solve the technical problem of unbalanced compression of luminance and chrominance components due to the difference in spatial sampling rate of the luminance and chrominance components in the image encoding process in the prior art, which wastes a considerable bit rate, the present invention provides a Chroma equalization method for video coding and chroma quantization parameter correction method for adaptively adjusting chroma component compression ratio

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