Domain block searching method for video denoising

Abstract

The invention discloses a domain block searching method for video denoising. The domain block searching method comprises the following steps of: calculating an optical flow field of a current frame and previous and succeeding reference frames of the current frame by using an optical flow algorithm; selecting a current block; determining a searching range of the current frame and the previous and succeeding reference frames according to the optical flow field; performing test matching on all blocks within the searching range of the current frame and the previous and succeeding reference frames; and selecting domain blocks of the current block from all the blocks within the searching range of the current frame and the previous and succeeding frames according to test matching results. When the method is applied to a block matching with three-dimensional transform domain collaborative filtering (BM3D) algorithm, the shortcoming of subjective and objective performance degradation of the BM3D algorithm in a motion scene can be overcome, and moreover, smooth and little-flicker high-quality denoised images can be obtained in each scene.

Description

technical field [0001] The invention relates to the field of digital video, in particular to a similar block search method for video noise reduction. Background technique [0002] The BM3D algorithm and its video noise reduction extension VBM3D and its derivative algorithms (hereinafter collectively referred to as BM3D) are currently known general-purpose image / video noise reduction algorithms with the highest performance. Effective noise reduction. [0003] like figure 1 As shown, the BM3D algorithm consists of three basic steps: similar block search, 3D transform domain noise reduction, and aggregation, and can be iteratively operated multiple times, of which the standard BM3D algorithm is two iterations. In the similar block search step, BM3D in the current frame and before and after each N FR Search and match blocks similar to the current two-dimensional block P in the frame, and form similar blocks into a three-dimensional array; in the 3D transformation domain noise...

AI Technical Summary

Problems solved by technology

[0018] In order to overcome the shortcomings of the BM3D method in the prior art that it is difficult to obtain optimized results in both moving and static scenes, fast moving and slow moving scenes, and the performance drops significantly when the scene is violently moving, the main purpose of the present invention is to provide a A similar block search method for video noise reduction, which solves the defect of BM3D's subjective and objective performance degradation in moving scenes by combining optical flow algorithms, and can obtain smooth and rarely flickering high-resolution images in various scenes. Quality denoised image

Images