Reference variance and adjustment factor based wave atoms image speckle reduction method for optical coherence tomography images

Abstract

Speckle noise in optical coherence tomography (OCT) images causes blurring of small targets and structural edges in the image, which reduces the quality of OCT images. To address this problem, a reference variance and adjustment factor based wave atoms image speckle reduction method for OCT images is proposed. First, reference image and adjustment factor were introduced, and reference image speckle noise reference variance was adjusted using adjustment factor to obtain the target image speckle noise variance. Then, a wave atoms threshold equation including the reference variance and the adjustment factor was constructed to obtain an accurate wave atoms noise reduction threshold. On this basis, speckle noise was shrunk using the wave atoms noise reduction threshold to achieve speckle noise reduction in OCT images, and OCT images with clear small targets and sharp structure edges were obtained. The effectiveness and advantages of the proposed method were illustrated with human eye OCT image and retinal OCT image.