A method includes obtaining original image data and obtaining de-noised image data, wherein the de-noised image data is the original image data after de-noising the original image data. The method further includes determining a noise pattern for the original image data. The method further includes estimating underlying local structure from the original image data based on the noise pattern. The method further includes restoring low contrast structure that is lost during the de-noising of the original image data to the de-noised image data based on the estimated underlying local structure by adding the estimated underlying local structure to the de-noise imaged data, generating low contrast structure enhanced de-noised image data.