What are Visual Artifacts?
Visual artifacts are unintended distortions introduced during capture, processing, compression, transmission, scaling, or display. Examples include blocking, banding, ringing, mosquito noise, tearing, and dropped-frame judder.
How Visual Artifacts work
Artifacts have characteristic spatial and temporal signatures that help locate their origin in a media chain. Block boundaries and ringing often implicate transform compression, banding can expose limited precision or aggressive quantization, and tearing points to unsynchronized display updates rather than damaged encoded frames. Quality control compares the source, intermediate renders, encoded outputs, transmission logs, and displays to avoid treating every defect as a bitrate problem.
Key facts
- Blocking appears when transform and quantization decisions made per block leave discontinuous errors at block boundaries; neighboring blocks need not be independently coded. Ringing creates halos near sharp edges, and both defects can intensify under coarse quantization.
- Banding turns a smooth gradient into visible steps because too few distinct levels survive capture or processing; dithering can disguise the steps by trading them for controlled noise.
- Screen tearing can occur when a display presents portions of different frames in one refresh. Raising an encoder bitrate will not correct this synchronization failure.
When Visual Artifacts matter
Artifact review helps determine whether encoder settings, source damage, or processing stages degraded a video. Raising bitrate may reduce compression artifacts but cannot repair every capture or scaling defect.