Line pair

A line pair can be more than one thing.

A line pair in philately is a coil pair of postage stamps bearing an inked line between the two stamps. There are at least two kinds of these:

A line pair in image processing is this: on a test pattern consisting of closely spaced black parallel lines on a white background, a line pair is one black line together with the white space on one side of it. When photographers say "lines of resolution", they mean line pairs. In television and video, one line pair equals two TV lines or pixels, of resolution.

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