Region-based non-local means algorithm for noise removal

The non-local means (NLM) provides a useful tool for image denoising and many variations of the NLM method have been proposed. However, few works have tried to tackle the task of adaptively choosing the patch size according to region characteristics. Presented is a region-based NLM method for noise removal. The proposed method first analyses and classifies the image into several region types. According to the region type, a local window is adaptively adjusted to match the local property of a region. Experimental results show the effectiveness of the proposed method and demonstrate its superiority to the state-of-the-art methods.