A) artefacts can range from noise and snow, to spots. Anything that is visually wrong with the picture is an artifact. artefacts however do not include picture errors caused by improperly adjusted displays. artefacts are visual errors caused by the signal being sent to the display.

b) A defect or distortion of the image, introduced along the sequence from origination and image capture to final display. artefacts may arise from the overload of channel capacity by excess signal bandwidth. artefacts may also result from: sampling effects in temporal, spatial, or frequency domains; processing by the transfer functions; compromises any inadequacies in the system employed; cascading of minor defects; basically any other departure of the total system from “complete transparency.”

c) Visible (or audible) consequences of various television processes. artefacts are usually referred to only when they are considered defects. artefact elimination is often more apparent than quality increases such as resolution enhancement.

d) Interference or other unwanted “noise” in video such as flickering, changes in color, and macroblocking. Some artifacts, such as macroblocking, can be remedied in video compression and some cannot. The quality of the finished product is, in large part, no better than the source material.

See also philtre Artifacts, Impairments, and NTSC Artifacts.