Coding distortion removal method, video encoding method, video decoding method, and apparatus and program for the same

Abstract

Mosaic-shaped block noise occurs when a compressed video signal is reproduced. This block noise is removed, but removing block noise from every block using a deblocking filter imposes a significant load on the deblocking filter. This load is therefore reduced by determining whether coding distortion removal (deblocking) is necessary, and applying a deblocking filter only when needed.

1 . A coding distortion removal method for removing coding distortion in a picture composed of field structure blocks and frame structure blocks, comprising: 
 detecting whether a target block for coding distortion removal is coded as a field structure block or a frame structure block;    performing a coding distortion removal process on even field pixels of the target block and separately performing the coding distortion removal process on odd field pixels of the target block, when it is detected that the target block is coded as a field structure block; and    performing the coding distortion removal process on the target block without separating even field pixels and odd field pixels of the target block when it is detected that the target block is coded as a frame structure block,    wherein the coding distortion removal process comprises determining whether coding distortion removal is needed, determining the number of pixels to be processed, and removing coding distortion.