基于数学形态学的去方块效应法

Method for removal of blocking artifacts based on mathematical morphology

为了减少多分辨奇异值分解(MSVD)图像融合后的图像出现明显可见的方块效应,提出一种基于数学形态学的边缘检测去方块效应的方法.首先通过形态学梯度算子求出两幅原图像的边缘,将边缘融合后的图像作为有方块效应图像的边缘,然后根据形态学梯度逆变换得到结果图像.最后,采用客观性能指标对结果图像进行评价.实验结果表明本文中的方法不仅简单易行,而且图像可以达到较均匀的成像效果;方块效应去除后,图像表现出良好的视觉效果,清晰度和空间频率都有很大提高,且具有较好的保持边缘的性能.

In order to reduce the visible blocking artifacts in the fused image with Multi-resolution singular value decomposition（MSVD）, a blocking-artifact reduction algorithm based on mathematical morphology edge detection was presented in this paper. Both edges of the two original images were figured out using morphological gradient operator. The image fusion was performed for the two edges. Then the fused edge image could be as the edge of image with blocking artifacts. The result image with no blocking artifacts was obtained using inverse transformation of morphological gradient. At last, the performance of the result image evaluated using objective indices. The experimental result showed that the proposed method was not only simple, but also uniformed the image. After reducing blocking-artifact, the visual effect of the image was considerable. It also showed that both the definition and spatial frequency was improved greatly, and was more powerful in edge-preserving.