二进小波与扩散滤波结合的光学相干层析图像降噪

斑点抑制各向异性扩散(SRAD)是一种重要的图像降噪方法。将二进小波与SRAD结合,提出一种光学相干层析图像的二进小波扩散滤波降噪方法。该方法利用二进小波分解得到的不同尺度间小波系数的相关性区分边缘和噪声,修改SRAD中扩散系数得到新的扩散系数计算公式。实验表明,新方法具有更好的降噪能力,降噪后得到的图像的信噪比和对比度噪声比率等量化衡量指标都优于经典SRAD方法。

Optical coherence tomography image denoising method by merging dyadic wavelet and anisotropic diffusion filter

Speckle reduction anisotropic diffusion(SRAD)is an important method to denoise speckle noise.A new method was presented to denoise optical coherence tomography(OCT) speckle by combining SRAD and dyadic wavelet.Interscale dependency of dyadic wavelet coefficients was used to distinguish edges from noises.A quantitative estimation was provided to evaluate the probability that a pixel lied in edge-related regions or homogenous regions,and the probability was used to modify the diffusion coefficient in SRAD to get a new anisotropic diffusion method,which exhibited an increased ability to detect and suppress strong noises,while still equally was good at preserving image edges.Experiments show that the denoising performance of our method is better than that of SRAD.