Anisotropic Diffusion Transform Based on Directions of Edges

This paper provides the derivation of speckle reducing anisotropic diffusion (SRAD), anisotropic diffusion method tailored to ultrasonic imaging applications. The conventional anisotropic diffusion is performed in four directions without condition in the previous method. In this paper, a new anisotropic diffusion transform based on directions of edges is proposed. The proposed diffusion is not performed at a pixel which is not an edge. The range of proposed diffusion is selected adaptively according to the number of the directions of edges. Experiments results show that the process time of the proposed method over conventional methods, can be faster slightly. Also, the proposed method can improve the image quality of diagonal edges in ultrasound image with speckle noise.