In digital holography, the inherited speckle noise degrades imaging quality due to the coherent laser source. To overcome this problem, a hybrid method for speckle noise reduction is presented by combining a novel angular diversity approach with the block-matching and 3D filtering (BM3D) algorithm. A serial of holograms is first captured by the proposed recording approach, and then the image with high signal-to-noise ratio is obtained by averaging multiple reconstructed intensity images. Finally, the residual noise in the averaged image is further eliminated by the BM3D filtering algorithm. The speckle noise is significantly suppressed, and a nearly speckle-free image can be obtained. Experimental results demonstrate the effectiveness of the proposed method.

中文翻译：

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用于数字全息术中减少斑点噪声的混合方法。

在数字全息术中，由于相干激光源，遗传的斑点噪声会降低成像质量。为了克服这个问题，提出了一种用于减少斑点噪声的混合方法，该方法通过将新颖的角度分集方法与块匹配和3D滤波（BM3D）算法相结合而提出。首先通过提出的记录方法捕获一系列全息图，然后通过平均多个重建的强度图像来获得具有高信噪比的图像。最后，通过BM3D滤波算法进一步消除了平均图像中的残留噪声。斑点噪声被显着抑制，并且可以获得几乎没有斑点的图像。实验结果证明了该方法的有效性。