struct GimpHSL

struct GimpHSL {

  gdouble h, s, l, a;
};

gimp_rgb_to_hsv ()

void        gimp_rgb_to_hsv                 (const GimpRGB *rgb,
                                             GimpHSV *hsv);

Does a conversion from RGB to HSV (Hue, Saturation, Value) colorspace.

gimp_rgb_to_hsl ()

void        gimp_rgb_to_hsl                 (const GimpRGB *rgb,
                                             GimpHSL *hsl);

Convert an RGB color value to a HSL (Hue, Saturation, Lightness) color value.

gimp_rgb_to_cmyk ()

void        gimp_rgb_to_cmyk                (const GimpRGB *rgb,
                                             gdouble pullout,
                                             GimpCMYK *cmyk);

Does a naive conversion from RGB to CMYK colorspace. A simple formula that doesn't take any color-profiles into account is used. The amount of black pullout how can be controlled via the pullout parameter. A pullout value of 0 makes this a conversion to CMY. A value of 1 causes the maximum amount of black to be pulled out.

gimp_hsv_to_rgb ()

void        gimp_hsv_to_rgb                 (const GimpHSV *hsv,
                                             GimpRGB *rgb);

Converts a color value from HSV to RGB colorspace

gimp_hsl_to_rgb ()

void        gimp_hsl_to_rgb                 (const GimpHSL *hsl,
                                             GimpRGB *rgb);

Convert a HSL color value to an RGB color value.

gimp_cmyk_to_rgb ()

void        gimp_cmyk_to_rgb                (const GimpCMYK *cmyk,
                                             GimpRGB *rgb);

Does a simple transformation from the CMYK colorspace to the RGB colorspace, without taking color profiles into account.

gimp_rgb_to_hwb ()

void        gimp_rgb_to_hwb                 (const GimpRGB *rgb,
                                             gdouble *hue,
                                             gdouble *whiteness,
                                             gdouble *blackness);

Theoretically, hue 0 (pure red) is identical to hue 6 in these transforms. Pure red always maps to 6 in this implementation. Therefore UNDEFINED can be defined as 0 in situations where only unsigned numbers are desired.

RGB are each on [0, 1]. Whiteness and Blackness are returned in the range [0, 1] and H is returned in the range [0, 6]. If W == 1 - B, H is undefined.

gimp_hwb_to_rgb ()

void        gimp_hwb_to_rgb                 (gdouble hue,
                                             gdouble whiteness,
                                             gdouble blackness,
                                             GimpRGB *rgb);

H is defined in the range [0, 6] or UNDEFINED, B and W are both in the range [0, 1]. The returned RGB values are all in the range [0, 1].

gimp_rgb_to_hsv_int ()

void        gimp_rgb_to_hsv_int             (gint *red,
                                             gint *green,
                                             gint *blue);

The arguments are pointers to int representing channel values in the RGB colorspace, and the values pointed to are all in the range [0, 255].

The function changes the arguments to point to the HSV value corresponding, with the returned values in the following ranges: H [0, 360], S [0, 255], V [0, 255].

gimp_hsv_to_rgb_int ()

void        gimp_hsv_to_rgb_int             (gint *hue,
                                             gint *saturation,
                                             gint *value);

The arguments are pointers to int, with the values pointed to in the following ranges: H [0, 360], S [0, 255], V [0, 255].

The function changes the arguments to point to the RGB value corresponding, with the returned values all in the range [0, 255].

gimp_rgb_to_hsl_int ()

void        gimp_rgb_to_hsl_int             (gint *red,
                                             gint *green,
                                             gint *blue);

The arguments are pointers to int representing channel values in the RGB colorspace, and the values pointed to are all in the range [0, 255].

The function changes the arguments to point to the corresponding HLS value with the values pointed to in the following ranges: H [0, 360], L [0, 255], S [0, 255].

gimp_rgb_to_cmyk_int ()

void        gimp_rgb_to_cmyk_int            (gint *red,
                                             gint *green,
                                             gint *blue,
                                             gint *pullout);

Does a naive conversion from RGB to CMYK colorspace. A simple formula that doesn't take any color-profiles into account is used. The amount of black pullout how can be controlled via the pullout parameter. A pullout value of 0 makes this a conversion to CMY. A value of 100 causes the maximum amount of black to be pulled out.

gimp_cmyk_to_rgb_int ()

void        gimp_cmyk_to_rgb_int            (gint *cyan,
                                             gint *magenta,
                                             gint *yellow,
                                             gint *black);

Does a naive conversion from CMYK to RGB colorspace. A simple formula that doesn't take any color-profiles into account is used.

gimp_rgb_to_l_int ()

gint        gimp_rgb_to_l_int               (gint red,
                                             gint green,
                                             gint blue);

Calculates the lightness value of an RGB triplet with the formula L = (max(R, G, B) + min (R, G, B)) / 2

gimp_hsl_to_rgb_int ()

void        gimp_hsl_to_rgb_int             (gint *hue,
                                             gint *saturation,
                                             gint *lightness);

The arguments are pointers to int, with the values pointed to in the following ranges: H [0, 360], L [0, 255], S [0, 255].

The function changes the arguments to point to the RGB value corresponding, with the returned values all in the range [0, 255].

gimp_rgb_to_hsv4 ()

void        gimp_rgb_to_hsv4                (guchar *rgb,
                                             gdouble *hue,
                                             gdouble *saturation,
                                             gdouble *value);

gimp_hsv_to_rgb4 ()

void        gimp_hsv_to_rgb4                (guchar *rgb,
                                             gdouble hue,
                                             gdouble saturation,
                                             gdouble value);