1. A method, comprising: determining matching patches that match an image patch in a reference frame selected from a sequence of image frames; computing a noise estimate based on optical flow for previous image frames and for subsequent image frames relative to the reference frame in the sequence of the image frames; determining, based on the optical flow computations, similar motion patches from the previous and subsequent image frames that correspond to the image patch in the reference frame; and denoising the image patch in the reference frame based on the matching patches that are determined from within the reference frame and based on the similar motion patches that are determined from the previous and subsequent image frames.