  Poisson noise suppression is an important preprocessing step in several
applications, such as medical imaging, microscopy, and astronomical imaging. In
this work, we propose a novel patch-wise Poisson noise removal strategy, in
which the MMSE estimator is utilized in order to produce the denoising result
for each image patch. Fast and accurate computation of the MMSE estimator is
carried out using k-d tree search followed by search in the K-nearest neighbor
graph. Our experiments show that the proposed method is the preferable choice
for low signal-to-noise ratios.
