To address this problem, the Tchebichef moments based nonlocal means (TNLM) method is proposed for speckle suppression. Distinctively, he TNLM method determines the nonlocal self-similarities of the OCT images by computing the Euclidean distance between Tchebichef moments of two image patches centered at two pixels of interest in the prefiltered image. Due to the superior feature representation capability of Tchebichef moments, the proposed method can utilize more image structural information for the accurate computation of image self-similarities. The experiments on the clinical OCT images indicate that the TNLM method outperforms numerous despeckling methods in that it can suppress speckle noise more effectively while preserving image details better in terms of human vision, and it can provide higher signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), equivalent number of looks (ENL) and cross correlation (XCOR).
ACCESS THE FULL ARTICLE
Wanying Jiang, Wenqi Xiang, Mingyue Ding, Xuming Zhang, "Tchebichef moments based nonlocal-means method for despeckling optical coherence tomography images," Proc. SPIE 9413, Medical Imaging 2015: Image Processing, 941327 (20 March 2015);