A filter for video coding is configured for processing a block for generation of a filtered block, where the block comprises a plurality of pixels. The filter includes one or more processor configured to: scan a current pixel of the block and its neighboring pixels of the current pixel according to a predefined scan template, obtain spectrum components by performing transform for the current pixel and its neighboring pixels, obtain filtered spectrum components based on a filtering parameter and the spectrum components, obtain filtered pixels by performing inverse transform for the filtered spectrum components, and generate a filtered block based on the filtered pixels.