基于RGB色彩空间的彩色图像混合编码

Color Image Hybrid Coding Based on RGB Color Space

在RGB色彩空间,利用彩色图像3个色彩分量之间存在的密切的相关性,建立它们之间的多项式相关函数。选择其中一个色彩分量用JPEG2000进行编码,依据该色彩分量与另两个色彩分量的差值分布均匀程度,用四叉树算法将图像分割成若干个不重叠的子块,用多项式相关函数计算出每个子块色彩分量之间的相关系数,由此对另两个色彩分量的编码就转变成对相关系数的编码。解码则是通过JPEG2000的逆变换得到一个重构的色彩分量,再由这个重构的色彩分量和重构的相关系数解得另两个色彩分量。实验结果表明,该方法不仅编解码速度快,而且信噪比、压缩比及视觉效果明显优于JPEG2000等算法的编码结果。

In RGB color space, the polynomial correlation functions are established between three color componems using the close correlation certainly exist between three color components. One of the three color components is coded using JPFG2000 coding, and the image is segmented into multi-subregions with non-overlapping by quadtree partitioning according to its degree of homogeneous distribution of ehromatism of that the component with other two components. Based on the calculated correlation coefficients by the polynomial correlation functions in every subregion, the coding for the other two components becomes the coding of correlation coefficients. During decoding, the component is reconstructed using the inverse transform of JPEG2000. Then according to this reconstructed component and the reconstructed correlation coefficients, the other two components are calculated out. Experiment results show that this method is of high coding and decoding rates, and its signal to noise ratio, compression rate and visual quality are better than those of JPEG2000.