blocking artifacts

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blocking artifacts

A distortion that appears in compressed video material as abnormally large pixel blocks. Also called "macroblocking," it occurs when the encoder cannot keep up with the allocated bandwidth. It is especially visible with fast motion sequences or quick scene changes.

Video uses lossy compression, and the higher the compression rate, the more content is removed. At decompression, the output of certain decoded blocks makes surrounding pixels appear averaged together and look like larger blocks. As TVs get larger, blocking and other artifacts become more noticeable. See artifact and pixelated.


Before and After
The lines at the edge of the original frame are used to point to the blocking artifacts, which are removed with Algolith's MPEG Noise Reduction system. Both images are enlarged to show details. (Image courtesy of Algolith inc., www.algolith.com)
References in periodicals archive ?
The LBT increases the coding gain and reduces the blocking artifact but it has more ringing artifacts.
To reduce the blocking artifact, LF components are smoothened in the adjacent LF blocks and invalid HF components are discarded.
Blocking artifacts occur when there are signal discontinuities at block boundaries (Chen, T.
It also features Dynamic Deblocking (DDb[TM]) which smoothes blocking artifacts that are common in MPEG encoded content.
Better picture quality, achieved by avoiding blocking artifacts and other visible problems caused by video compression algorithms.
higher resolution without noise and blocking artifacts, even at high compression