aliasing

Aliasing

Used in the context of processing digitized signals (e.g. audio) and images (e.g. video), aliasing describes the effect of undersampling during digitization which can generate a false (apparent) low frequency for signals, or staircase steps along edges in images (jaggies.) Aliasing can be avoided by an antialiasing (analogue) low-pass filter, before sampling. The term antialiasing is also in use for a posteriori signal smoothing intended to remove the effect.

References

• Based on content from The Data Analysis Briefbook (http://rkb.home.cern.ch/rkb/titleA.html)