Forward-and-backward diffusion processes for adaptive image enhancement and denoising
Forward-and-backward diffusion processes for adaptive image enhancement and denoising
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DOI：
10.1109/tip.2002.800883
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发表时间：
2002-07-01
影响因子：
10.6
通讯作者：
Zeevi, YY
中科院分区：
文献类型：
--
作者：
Gilboa, G;Sochen, N;Zeevi, YY
信号和图像增强是在一种新型扩散过程的背景下考虑的，该扩散过程同时增强、锐化和去噪图像。非线性扩散系数根据边缘、纹理和矩等图像特征进行局部调整。因此，它可以根据给定的一组标准将扩散过程从正向模式切换到后向(反向)模式。这导致了前向和后向(FAB)自适应扩散过程，该过程增强了特征，同时局部地去噪了信号或图像的更平滑的部分。通过自适应地修改控制非线性扩散过程的结构张量，将FAB方法进一步推广到Beltrami流的色彩处理中。所提出的结构张量既不是正定的，也不是负的，而是根据图像特征在这些状态之间切换。这导致了向前和向后扩散流，其中图像的不同区域根据邻域内的局部几何形状向前或向后扩散。
Signal and image enhancement is considered in the context of a new type of diffusion process that simultaneously enhances, sharpens, and denoises images. The nonlinear diffusion coefficient is locally adjusted according to image features such as edges, textures, and moments. As such, it can switch the diffusion process from a forward to a backward (inverse) mode according to a given set of criteria. This results in a forward-and-backward (FAB) adaptive diffusion process that enhances features while locally denoising smoother segments of the signal or image. The proposed method, using the FAB process, is applied in a super-resolution scheme.The FAB method is further generalized for color processing via the Beltrami flow, by adaptively modifying the structure tensor that controls the nonlinear diffusion process. The proposed structure tensor is neither positive definite nor negative, and switches between these states according to image features. This results in a forward-and-backward diffusion flow where different regions of the image are either forward or backward diffused according to the local geometry within a neighborhood.