40 lines
1.3 KiB
Groff
40 lines
1.3 KiB
Groff
.TH LIGHT_CORRECT 1 "14 Oct 1996"
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.SH NAME
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light_correct \- correct illumination errors on set of images
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.SH SYNOPSIS
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.B light_correct grey image1 image2 image3 ...
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.SH DESCRIPTION
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The first argument should be an image of a piece of grey card, subsequent
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arguments should be images taken with the same lighting set-up which need
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correcting. The corrected images are written to files prefixed with "ic_".
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For example, suppose you have a directory with the following files in:
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example% ls
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dat1.1.v dat1.2.v dat2.1.v dat2.2.v dat3.1.v dat3.2.v
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dat4.1.v dat4.2.v grey.v
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then run light_correct like this:
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example% light_correct grey.v dat*.v
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to generate this:
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example% ls
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dat1.1.v dat1.2.v dat2.1.v dat2.2.v dat3.1.v dat3.2.v
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dat4.1.v dat4.2.v grey.v
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ic_dat1.1.v ic_dat1.2.v ic_dat2.1.v ic_dat2.2.v ic_dat3.1.v
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ic_dat3.2.v ic_dat4.1.v ic_dat4.2.v
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light_correct works by smoothing out the grey card image, finding
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grey-mean/pixel for each point, and then multiplying the result by all the
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following images. It also removes any .desc files it generates, to avoid
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problems with im_global_balance(3).
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.SH RETURN VALUE
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returns 0 on success and non-zero on error.
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.SH SEE ALSO
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header(1), vips(1)
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.SH COPYRIGHT
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The National Gallery and Birkbeck College, 1989-1996.
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