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Pixel-based speckle adjustment for noise reduction in Fourier-domain OCT images
Anqi Zhang1,2, Jiefeng Xi1, Jitao Sun3
1Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205, USA.
Abstract:
Speckle resides in OCT signals and inevitably effects OCT image quality. In this work, we present a novel method for speckle noise reduction in Fourier-domain OCT images, which utilizes the phase information of complex OCT data. In this method, speckle area is pre-delineated pixelwise based on a phase-domain processing method and then adjusted by the results of wavelet shrinkage of the original image. Coefficient shrinkage method such as wavelet or contourlet is applied afterwards for further suppressing the speckle noise. Compared with conventional methods without speckle adjustment, the proposed method demonstrates significant improvement of image quality.
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