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Diffstat (limited to '')
| -rw-r--r-- | src/libclut.h | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/src/libclut.h b/src/libclut.h index 973ac0a..9f3326b 100644 --- a/src/libclut.h +++ b/src/libclut.h @@ -23,6 +23,94 @@ +/** + * Initialiser for `struct libclut_rgb_colourspace` with the values + * of the sRGB colour space. + */ +#define LIBCLUT_RGB_COLOURSPACE_SRGB_INITIALISER \ + { \ + .red_x = 0.6400, .red_y = 0.3300, .red_Y = 0.212656, \ + .green_x = 0.3000, .green_y = 0.6000, .green_Y = 0.715158, \ + .blue_x = 0.1500, .blue_y = 0.0600, .blue_Y = 0.072186, \ + .white_x = 0.31271, .white_y = 0.32902, .white_Y = 1.0000 \ + } + + + +/** + * RGB colour space structure. + */ +typedef struct libclut_rgb_colourspace +{ + /** + * The x-component of the red colour's xyY value. + */ + double red_x; + + /** + * The y-component of the red colour's xyY value. + */ + double red_y; + + /** + * The Y-component of the red colour's xyY value. + */ + double red_Y; + + /** + * The x-component of the green colour's xyY value. + */ + double green_x; + + /** + * The y-component of the green colour's xyY value. + */ + double green_y; + + /** + * The Y-component of the green colour's xyY value. + */ + double green_Y; + + /** + * The x-component of the blue colour's xyY value. + */ + double blue_x; + + /** + * The y-component of the blue colour's xyY value. + */ + double blue_y; + + /** + * The Y-component of the blue colour's xyY value. + */ + double blue_Y; + + /** + * The x-component of the white point's xyY value. + */ + double white_x; + + /** + * The y-component of the white point's xyY value. + */ + double white_y; + + /** + * The Y-component of the white point's xyY value. + */ + double white_Y; +} libclut_rgb_colourspace_t; + + +/** + * Matrix date-type for colourspace conversion. + */ +typedef double libclut_colourspace_conversion_matrix_t[3][3]; + + + /* This is to avoid warnings about comparing double, These are only * used when it is safe, for example to test whether optimisations * are possible. { */ @@ -1082,6 +1170,9 @@ static inline int libclut_0__(double x) { return libclut_eq__(x, 0); } (size_t)((double)(i) * (double)(out) / (double)(in)) +/* TODO libclut_convert_rgb */ + + #if defined(__GNUC__) && !defined(__clang__) # define LIBCLUT_GCC_ONLY__(x) x @@ -1390,6 +1481,60 @@ void (libclut_model_cielab_to_ciexyz)(double, double, double, double*, double*, (((C)*(C)*(C) > 0.00885642) ? ((C)*(C)*(C)) : (((C) - 0.1379310) / (7.78 + 703.0 / 99900))) +/** + * Create a matrix for converting values between + * two RGB colourspaces. + * + * @param from The input colourspace, the Y-component is only necessary for the whitepoint. + * @param to The output colourspace, the Y-component is only necessary for the whitepoint. + * @param M Output matrix for conversion from `from` to `to`. + * @param Minv Output matrix for conversion from `to` to `from`, may be `NULL`. + * @return Zero on success, -1 on error. + * + * @throws EINVAL The colourspace cannot be used. + */ +LIBCLUT_GCC_ONLY__(__attribute__((__leaf__))) +int libclut_model_get_rgb_conversion_matrix(const libclut_rgb_colourspace_t*, + const libclut_rgb_colourspace_t*, + libclut_colourspace_conversion_matrix_t, + libclut_colourspace_conversion_matrix_t); +/* TODO doc libclut_model_get_rgb_conversion_matrix */ + + +/** + * Convert an RGB colour into another RGB colourspace. + * None of the parameter may have side-effects. + * + * Requires linking with '-lclut', or '-lm' if + * `libclut_model_standard_to_linear1` or + * `libclut_model_linear_to_standard1` is not undefined. + * + * @param r The red component of the colour to convert. + * @param g The green component of the colour to convert. + * @param b The blue component of the colour to convert. + * @param M Conversion matrix, create with `libclut_model_get_rgb_conversion_matrix`, + * must not have side-effects (unless libclut_model_convert_rgb1 is undefined). + * @param out_r Output parameter for the new red component. + * @param out_g Output parameter for the new green component. + * @param out_b Output parameter for the new blue component. + */ +LIBCLUT_GCC_ONLY__(__attribute__((__leaf__))) +void (libclut_model_convert_rgb)(double, double, double, libclut_colourspace_conversion_matrix_t, + double *, double *, double *); +#define libclut_model_convert_rgb(r, g, b, M, out_r, out_g, out_b) \ + do \ + { \ + double r__ = libclut_model_standard_to_linear1(r); \ + double g__ = libclut_model_standard_to_linear1(g); \ + double b__ = libclut_model_standard_to_linear1(b); \ + *(out_r) = libclut_model_linear_to_standard1((M)[0][0] * r__ + (M)[0][1] * g__ + (M)[0][2] * b__); \ + *(out_g) = libclut_model_linear_to_standard1((M)[1][0] * r__ + (M)[1][1] * g__ + (M)[1][2] * b__); \ + *(out_b) = libclut_model_linear_to_standard1((M)[2][0] * r__ + (M)[2][1] * g__ + (M)[2][2] * b__); \ + } \ + while (0) +/* TODO libclut_model_convert_rgb */ + + #if defined(__clang__) # pragma GCC diagnostic pop |