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aliasing

A Dictionary of Computing | 2004 | | Copyright

aliasing A distorting effect caused by sampling an image at too low a rate. When a signal is undersampled, high-frequency components cannot be distinguished from lower-frequency components. Thus the higher frequencies assume the alias (or false identity) of the lower frequencies. Some common computer-graphics artefacts due to aliasing are jagged lines, small objects missing from a scene, and jerky motion. Aliasing effects can be removed or subdued by anti-aliasing. Fine detail, such as mesh curtains, can be totally lost or distorted without anti-aliasing. Aliasing effects are even more prominent in animated images.

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JOHN DAINTITH. "aliasing." A Dictionary of Computing. 2004. Encyclopedia.com. 28 May. 2012 <http://www.encyclopedia.com>.

JOHN DAINTITH. "aliasing." A Dictionary of Computing. 2004. Encyclopedia.com. (May 28, 2012). http://www.encyclopedia.com/doc/1O11-aliasing.html

JOHN DAINTITH. "aliasing." A Dictionary of Computing. 2004. Retrieved May 28, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O11-aliasing.html

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aliasing

A Dictionary of Earth Sciences | 1999 | | Copyright

aliasing A distortion in the frequency of sampled data produced by insufficient sampling per wavelength, which can result in spurious frequencies. When the sampling rate is too low to represent the wave-form accurately, then aliasing will occur. To avoid aliasing, the sampling frequency should be at least twice that of the highest-frequency component contained within the sampled wave-form. Alternatively, an anti-alias filter can be applied, which removes frequency components above the Nyquist frequency.

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AILSA ALLABY and MICHAEL ALLABY. "aliasing." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 28 May. 2012 <http://www.encyclopedia.com>.

AILSA ALLABY and MICHAEL ALLABY. "aliasing." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (May 28, 2012). http://www.encyclopedia.com/doc/1O13-aliasing.html

AILSA ALLABY and MICHAEL ALLABY. "aliasing." A Dictionary of Earth Sciences. 1999. Retrieved May 28, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-aliasing.html

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aliasing

A Dictionary of Astronomy | 1997 | Copyright

aliasing A phenomenon in which a digitized signal is observed to contain spurious low-frequency components. These occur if the original signal is sampled at a rate insufficient to record the highest frequencies present (undersampling).

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"aliasing." A Dictionary of Astronomy. 1997. Encyclopedia.com. 28 May. 2012 <http://www.encyclopedia.com>.

"aliasing." A Dictionary of Astronomy. 1997. Encyclopedia.com. (May 28, 2012). http://www.encyclopedia.com/doc/1O80-aliasing.html

"aliasing." A Dictionary of Astronomy. 1997. Retrieved May 28, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-aliasing.html

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Free newspaper and magazine articles

	Time-domain analysis of aliasing helps to alleviate DSO errors. (digital... Magazine article from: EDN; 9/15/1988
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