Video comfort noise addition technique

Abstract

A decoding arrangement (10, 100, 1000) for decoding pictures in an incoming video stream includes a noise generator (16 ) for adding a dither signal containing random noise to the pictures after video decoding, to improve the subjective video quality. The noise generator adds noise to each pixel in an amount correlated to the luminance of at least a portion of the current picture.

Description

[0001] Cross References to Related Applications [0002] This application claims priority to US Provisional Patent Application Serial No. 60 / 505,254, filed September 23, 2003, the teachings of which are incorporated herein. technical field [0003] The present invention relates to a technique for reducing artifacts associated with the decoding of encoded video streams. Background technique [0004] Decoding of video streams compressed at low bit rates often produces visible artifacts that can be perceived by the viewer. Blockiness and structured noise patterns are common artifacts that appear when using block-based compression techniques. The human visual system is more sensitive to certain types of artifacts, and as such, these artifacts are more perceptible and objectionable than others. Adding random noise to the decoded stream can make these compression artifacts less noticeable, but the large frame-to-frame variance caused by adding random noise can itself produce eas...

AI Technical Summary

Problems solved by technology

Adding random noise to the decoded stream can make these compression artifacts less noticeable, but the large frame-to-frame variance caused by adding random noise can itself produce easily noticeable and unpleasant artifacts

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