Techniques for method for filtering artifacts from digital video are disclosed. In an example, a method includes accessing a video stream that includes a block with sub-blocks. The method includes, for each candidate filter strength parameter of a set of candidate filter strength parameters associated with the block, filtering each sub-block using a filter having the candidate filter strength parameter, creating a filtered block by combining the filtered sub-blocks, and calculating, for the filtered block, a distortion error measurement between a corresponding source block and the filtered block. The method includes selecting the filter strength parameters associated with a lowest distortion error measurement of the distortion error measurements. The method includes applying the selected filter strength parameters to an in-loop deringing filter to generate a filtered block of video.