A method for decoding an image block includes receiving a quantized transform block; generating a decoded block from the quantized transform block; applying an edge-preserving filter to the decoded block, to obtain an edge-filtered decoded block; obtaining a transformed edge-preserved block using a transform type and quantization data to the edge-filtered decoded block; clamping a value of the transformed edge-preserved block to a corresponding value of the quantized transform block to obtain a smoothed transform block; and inverse transforming the smoothed transform block to obtain an edge-preserved smoothed block. The applying an edge-preserving filter to the decoded block includes determining respective patch-based distances between a pixel of the decoded block and neighboring pixels; determining respective weights corresponding to the respective patch-based distances; and filtering the pixel using the respective weights and the neighboring pixels.