1RGBYIQ(3NCARG) NCAR GRAPHICS RGBYIQ(3NCARG)
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6 RGBYIQ - Converts a color specification given in the RGB Red, Green,
7 Blue, (RGB) color space to a color specification in the YIQ color
8 space.
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11 CALL RGBYIQ (R, G, B, Y, I, Q)
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14 #include <ncarg/ncargC.h>
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16 void c_rgbyiq (float r, float g, float b, float *y,
17 float *i, float *q)
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20 R (REAL, input, range [0.,1.]) represents the red intensity
21 component of the input point in RGB color space.
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23 G (REAL, input, range [0.,1.]) represents the green
24 intensity component of the input point in RGB color space.
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26 B (REAL, input, range [0.,1.]) represents the blue intensity
27 component of the input point in RGB color space.
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29 Y (REAL, output, range [0.,1.]) This is the color component
30 of a television signal that is shown on black-and-white
31 televisions; Y minimizes the effect of two colors appearing
32 different to the human eye but mapping to similar
33 monochrome intensities.
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35 I (REAL, output, range [-.6,.6]) attains its maximum when the
36 input triple is (1.,0.,0.); I attains its minimum when the
37 input triple is (0.,1.,1.).
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39 Q (REAL, output, range [-.52,.52]) attains its maximum when
40 the input triple is (1.,0.,1.); Q attains its minimum when
41 the input triple is (0.,1.,0.).
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44 The C-binding argument descriptions are the same as the FORTRAN
45 argument descriptions.
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48 Use the ncargex command to see the following relevant example: tcolcv,
49 fcce02.
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52 To use RGBYIQ or c_rgbyiq, load the NCAR Graphics libraries ncarg,
53 ncarg_gks, and ncarg_c, preferably in that order.
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56 Online: colconv, hlsrgb, hsvrgb, rgbhls, rgbhsv, yiqrgb, ncarg_cbind.
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58 Hardcopy: NCAR Graphics Fundamentals, UNIX Version
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61 Copyright (C) 1987-2009
62 University Corporation for Atmospheric Research
63 The use of this Software is governed by a License Agreement.
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67UNIX March 1993 RGBYIQ(3NCARG)