A method for enhancing quality of an image comprises deriving from an initial low-resolution image (LRI) an initial high-resolution image (IHRI) by upsampling (S2, S3), providing (S4), based on the initial low-resolution image (LRI), at least one downsampled filtered image (AIij, AIi′j′) with lower resolution, providing (S6), based on the initial low-resolution image (LRI), an unfiltered image (LRI, UIi′j′) having same resolution as the downsampled filtered image, selecting a patch (PI) from the initial high-resolution image (IHRI), finding (S8) filial patches (PA k) similar to the selected patch in the downsampled filtered image (AIij, AIi′j′), finding, in the unfiltered image (LRI, UIi′j′), parent patches (PPk) locally associated to the filial patches (PAk), and linearly combining (S14) the parent patches (PPk) to form an enhanced quality patch (EP). Finally, enhanced quality patches (EP) obtained by repeatedly carrying out above steps are combined (S15) to form an enhanced quality high-resolution image (EIp).