1. An apparatus, comprising: an encoder ( 400 , 600 , 800 ) for encoding at least a portion of an image by grouping regions within the portion based on a grouping metric, transforming the grouped regions, adaptively performing de-artifact filtering on the transformed regions using a de-artifacting filter ( 465 , 613 , 813 ) comprised in the encoder, inverse transforming the de-artifacted regions to create replacement regions, and restoring the replacement regions to positions with the image from which the regions were taken prior to the grouping.