关键词: 图像特征, 各向异性扩散, 相干性, 扩散张量, 特征值

Abstract: As for the image denoising filter method, the model proposed by J. Weickert does not consider the distinctions between the smooth area and other image features. The diffusion in smooth area is also in accordance with the eigenvalues of local structure characteristics, thus inevitably producing false edges in smooth area. An improved anisotropic diffusion method was proposed. This method firstly used the Wiener filter to weaken the influence of noise on the image, then coherence was applied to judge image feature correctly, as edge region, smooth area, T-shape corner and so on, and the diffusion tensor's eigenvalues in corresponding region were set based on image feature. The experimental results show that the improved method can not only achieve better results in elimination of noise and protection of edge, but also remove false edge in smooth area effectively and get higher peak signal-to-noise ratio.

Key words: image feature, anisotropic diffusion, coherence, diffusion tensor, eigenvalue