mlib_ImageColorHSL2RGB(3mlib)

1mlib_ImageColorHSL2RGB(3MLImBe)diaLib Library Functiomnlsib_ImageColorHSL2RGB(3MLIB)
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NAME

6       mlib_ImageColorHSL2RGB - HSL to RGB color conversion
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SYNOPSIS

9       cc [ flag... ] file... -lmlib [ library... ]
10       #include <mlib.h>
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12       mlib_status mlib_ImageColorHSL2RGB(mlib_image *dst, const mlib_image *src);
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DESCRIPTION

16       The   mlib_ImageColorHSL2RGB()  function  performs  a  conversion  from
17       hue/saturation/lightness to red/green/blue. The source and  destination
18       images must be three-channel images.
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21       It uses the following equations:
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23            L' = L          if L ≤ 1/2
24            L' = 1 - L      if L > 1/2
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26            V = L + S*L'
27            P = L - S*L'
28            Q = L + S*L'*(1 - 2*fraction(H*6))
29            T = L - S*L'*(1 - 2*fraction(H*6))
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31            R, G, B = V, T, P    if 0   ≤ H < 1/6
32            R, G, B = Q, V, P    if 1/6 ≤ H < 2/6
33            R, G, B = P, V, T    if 2/6 ≤ H < 3/6
34            R, G, B = P, Q, V    if 3/6 ≤ H < 4/6
35            R, G, B = T, P, V    if 4/6 ≤ H < 5/6
36            R, G, B = V, P, Q    if 5/6 ≤ H < 1
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40       where 0 ≤ H < 1 and 0 ≤ S, L, L', V, P, Q, T, R, G, B ≤ 1.
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43       Assuming a pixel in the source image is (h, s, l) and its corresponding
44       pixel in the destination image is (r, g, b), then for MLIB_BYTE images,
45       the following applies:
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47            H = h/256
48            S = s/255
49            L = l/255
50            r = R*255
51            g = G*255
52            b = B*255
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56       for MLIB_SHORT images, the following applies:
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58            H = (h + 32768)/65536
59            S = (s + 32768)/65535
60            L = (l + 32768)/65535
61            r = R*65535 - 32768
62            g = G*65535 - 32768
63            b = B*65535 - 32768
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67       for MLIB_USHORT images, the following applies:
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69            H = h/65536
70            S = s/65535
71            L = l/65535
72            r = R*65535
73            g = G*65535
74            b = B*65535
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78       and for MLIB_INT images, the following applies:
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80            H = (h + 2147483648)/4294967296
81            S = (s + 2147483648)/4294967295
82            L = (l + 2147483648)/4294967295
83            r = R*4294967295 - 2147483648
84            g = G*4294967295 - 2147483648
85            b = B*4294967295 - 2147483648
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PARAMETERS

89       The function takes the following arguments:
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91       dst    Pointer to destination image.
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94       src    Pointer to source image.
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RETURN VALUES

98       The  function  returns MLIB_SUCCESS if successful. Otherwise it returns
99       MLIB_FAILURE.
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ATTRIBUTES

102       See attributes(5) for descriptions of the following attributes:
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107       ┌─────────────────────────────┬─────────────────────────────┐
108       │      ATTRIBUTE TYPE         │      ATTRIBUTE VALUE        │
109       ├─────────────────────────────┼─────────────────────────────┤
110       │Interface Stability          │Committed                    │
111       ├─────────────────────────────┼─────────────────────────────┤
112       │MT-Level                     │MT-Safe                      │
113       └─────────────────────────────┴─────────────────────────────┘
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NAME

SYNOPSIS

DESCRIPTION

PARAMETERS

RETURN VALUES

ATTRIBUTES

SEE ALSO