Structure aware image denoising and noise variance estimation

A non-transitory system comprising:

• at least one processor;
• and
• at least one module implemented at least partially in hardware that, responsive to execution by the at least one processor, causes the at least one processor to perform structurally-aware denoising on an image to form a denoised image by:
• forming a plurality of potential reference patches from the image in which each potential reference patch of the plurality of potential reference patches includes a pixel;
• selecting a reference patch from the plurality of potential reference patches, the selecting based at least in part on the reference patch having a least amount of structure within the plurality of potential reference patches;
• computing a display value for the pixel to be included in the denoised image using a weighted comparison of the reference patch with a plurality of query patches;
• and
• outputting the denoised image having the computed display value for the pixel in the image.

A method of estimating noise variance in an image by at least one computing device for use in denoising the image, the method comprising:

• generating, by the at least one computing device, a denoised image by applying a patch-based denoising algorithm to the image;
• forming a map, by the at least one computing device, as having plurality of patches taken from the image, each of the plurality of patches including multiple pixels;
• identifying one or more regions of the image by the at least one computing device, each of the one or more regions comprising two or more patches of the plurality of patches in the map, the one or more regions identified based on the multiple pixels included in each of the plurality of patches having a variance, one to another, that is below a threshold, the variance indicative of a uniformity of the multiple pixels included in each of the plurality of patches;
• estimating the noise variance by the at least one computing device for the image, the estimated noise variance based on the two or more patches identified in the one or more regions in the image;
• using the estimated noise variance to calculate a value for at least one pixel in the image;
• and
• outputting the image with the calculated value for the at least one pixel.