1. A method of edge smoothing block filtering, comprising: selecting a current pixel as a pixel to be filtered; selecting a candidate pixel within a search area about the current pixel; computing a cost difference between pixels within a candidate pixel neighborhood about the candidate pixel and pixels within a current pixel neighborhood about the current pixel, wherein computing a cost difference comprises summing difference between each pixel within the candidate pixel neighborhood and a corresponding pixel within the current pixel neighborhood; converting the cost difference to a similarity measure based on a weight function and a smoothing noise threshold, the smoothing noise threshold associated with at least one of a local contrast strength or noise register values, the smoothing noise threshold determined by a function of a fixed threshold value and a value determined using a plurality of cost differences, wherein the similarity measure indicates a measure of filter strength; and filtering the current pixel based on the candidate pixel and the similarity measure, wherein filtering the current pixel comprises modifying the candidate pixel by a function of the similarity measure.