基于APBUT3的彩色图像编码与压缩研究

为实现彩色图像的有效压缩,采用一种基于全相位双正交三次U变换(All Phase Bi-orthogonal U TransformBased on 3-Degree U System,APBUT3)的新算法。该算法将原始彩色图像由RGB空间转换到YUV空间,利用APBUT3矩阵作为变换矩阵代替(Discrete Cosine Transform,DCT)对彩色图像的YUV三个分量分别进行压缩编码,编码时对变换系数采用均匀量化,可降低编码算法的时间复杂度。实验结果表明,较低压缩比时,该算法编码后的主观效果与DCT基本接近;较高压缩比时,采用16×16APBUT3编码的方块效应没有DCT明显。

Encoding and compression of color image based on APBUT3

To compress color images effectively, a new algorithm based on all phase bi-orthogonal U transform in 3-Degree U System （APBUT3） is proposed. By this algorithm, an original color image can be transformed from RGB space into YUV space, the three components of YUV can be compressed separately with an APBUT3 matrix working as the transformation matrix, and the transformed coefficients can be quantized uniformly while an image is encoded, which supersedes the discrete cosine transform （DCT）, so that, the time complexity can be reduced. Experimental results show that, a subjective effect of 16 × 16 APBUT3 is closed to that of the DOT encoding method when at a lower compression rate, however, when at a higher compression rate, the blocking effect of 16 × 16 APBUT3 is less obvious than that of DCT encoding method.