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Clipping

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Telecommunications

In telecommunication, the term clipping has the following meanings:

  1. In telephony, the loss of the initial or final parts of a word, words, or syllable, usually caused by the nonideal operation of voice-actuated devices.

  2. The limiting of instantaneous signal amplitudes to a predetermined maximum value.

  3. In a display device, the removal of those parts of display elements that lie outside of a given boundary.

(Source: from Federal Standard 1037C and from MIL-STD-188)

The clipping of a signal (audio, video, or radio) causes distortion.

Coins

For coins, clipping is the act of shaving off a small portion of the precious metal for profit. It was usually considered by the law to be of a similar nature to counterfeiting, and was even occasionally punished by death. A technological countermeasure was marking the rim of the coin with stripes, text or some pattern that would be destroyed if clipped.

Gardening

In gardening, clipping is equivalent to pruning, the practice of removing diseases, overmature or otherwise unwanted portions from a plant. Clipping typically involves much less removal than pruning, and is used more for herbaceous (all-green) plants than for woody ones.

Publications

Clipping is the cutting-out of articles from a paper publication. Newspaper clippings are often used when children have to write a report or make a presentation on current events for school. Clippings may also be kept by adults for future reference, or for sentimental reasons such as an article on a history-making event.


Computer Graphics

When rendering graphics, clipping refers to the task of making sure that only the visible part is actually drawn. This is non-trivial especially for 3D animations: if the objects are built up of, say, polygons, a routine is needed that determines fo each polygon whether it is visible within the viewport (i.e. the part of the 3D "world" displayed) or out off the borders. Special care is needed for the case of polygons intersected by the viewport border as their shape has to be adjusted.

Several clipping algorithms are known.