diff options
Diffstat (limited to 'src/libcolour.c')
-rw-r--r-- | src/libcolour.c | 834 |
1 files changed, 0 insertions, 834 deletions
diff --git a/src/libcolour.c b/src/libcolour.c index d2e056b..4ccb158 100644 --- a/src/libcolour.c +++ b/src/libcolour.c @@ -19,847 +19,13 @@ #include <alloca.h> #include <errno.h> #include <math.h> -#include <stdlib.h> -#include <stdio.h> #include <string.h> - #define MARSHAL_VERSION 0 -#define WASDIV0(x) (isinf(x) || isnan(x)) - - -static void to_rgb(const libcolour_colour_t* restrict from, libcolour_rgb_t* restrict to); -static void to_srgb(const libcolour_colour_t* restrict from, libcolour_srgb_t* restrict to); -static void to_ciexyy(const libcolour_colour_t* restrict from, libcolour_ciexyy_t* restrict to); -static void to_ciexyz(const libcolour_colour_t* restrict from, libcolour_ciexyz_t* restrict to); -static void to_cielab(const libcolour_colour_t* restrict from, libcolour_cielab_t* restrict to); -static void to_cieluv(const libcolour_colour_t* restrict from, libcolour_cieluv_t* restrict to); -static void to_cielchuv(const libcolour_colour_t* restrict from, libcolour_cielchuv_t* restrict to); -static void to_yiq(const libcolour_colour_t* restrict from, libcolour_yiq_t* restrict to); -static void to_ydbdr(const libcolour_colour_t* restrict from, libcolour_ydbdr_t* restrict to); -static void to_yuv(const libcolour_colour_t* restrict from, libcolour_yuv_t* restrict to); -static void to_ypbpr(const libcolour_colour_t* restrict from, libcolour_ypbpr_t* restrict to); -static void to_ycgco(const libcolour_colour_t* restrict from, libcolour_ycgco_t* restrict to); -static void to_cie1960ucs(const libcolour_colour_t* restrict from, libcolour_cie1960ucs_t* restrict to); -static void to_cieuvw(const libcolour_colour_t* restrict from, libcolour_cieuvw_t* restrict to); - - -static void ciexyz_to_rgb(const libcolour_ciexyz_t* restrict from, libcolour_rgb_t* restrict to) -{ - double X = from->X, Y = from->Y, Z = from->Z; - to->R = to->Minv[0][0] * X + to->Minv[0][1] * Y + to->Minv[0][2] * Z; - to->G = to->Minv[1][0] * X + to->Minv[1][1] * Y + to->Minv[1][2] * Z; - to->B = to->Minv[2][0] * X + to->Minv[2][1] * Y + to->Minv[2][2] * Z; -} - -static void to_rgb(const libcolour_colour_t* restrict from, libcolour_rgb_t* restrict to) -{ - int have_gamma = 0, with_gamma = to->with_gamma; - libcolour_ciexyz_t tmp; - switch (from->model) { - case LIBCOLOUR_CIEXYZ: - ciexyz_to_rgb(&from->ciexyz, to); - break; - case LIBCOLOUR_RGB: - if (!memcmp(from->rgb.M, to->M, sizeof(double[3][3]))) { - have_gamma = from->rgb.with_gamma; - *to = from->rgb; - break; - } - /* fall through */ - default: - tmp.model = LIBCOLOUR_CIEXYZ; - to_ciexyz(from, &tmp); - ciexyz_to_rgb(&tmp, to); - break; - } - - if (have_gamma != with_gamma) { - if (with_gamma) { - switch (to->encoding_type) { - case LIBCOLOUR_ENCODING_TYPE_LINEAR: - break; - case LIBCOLOUR_ENCODING_TYPE_SIMPLE: - to->R = pow(to->R, 1 / to->gamma); - to->G = pow(to->G, 1 / to->gamma); - to->B = pow(to->B, 1 / to->gamma); - break; - case LIBCOLOUR_ENCODING_TYPE_REGULAR: - to->R <= to->transition ? to->slope * to->R : (1 + to->offset) * pow(to->R, 1 / to->gamma) - to->offset; - to->G <= to->transition ? to->slope * to->G : (1 + to->offset) * pow(to->G, 1 / to->gamma) - to->offset; - to->B <= to->transition ? to->slope * to->B : (1 + to->offset) * pow(to->B, 1 / to->gamma) - to->offset; - break; - case LIBCOLOUR_ENCODING_TYPE_CUSTOM: - to->R = (to->to_encoded_red)(to->R); - to->G = (to->to_encoded_green)(to->G); - to->B = (to->to_encoded_blue)(to->B); - break; - default: - fprintf(stderr, "libcolour: invalid encoding type\n"); - abort(); - } - } else { - switch (to->encoding_type) { - case LIBCOLOUR_ENCODING_TYPE_LINEAR: - break; - case LIBCOLOUR_ENCODING_TYPE_SIMPLE: - to->R = pow(to->R, to->gamma); - to->G = pow(to->G, to->gamma); - to->B = pow(to->B, to->gamma); - break; - case LIBCOLOUR_ENCODING_TYPE_REGULAR: - to->R <= to->transitioninv ? to->R * to->slope : pow((to->R + to->offset) / (1 + to->offset), to->gamma); - to->G <= to->transitioninv ? to->G * to->slope : pow((to->G + to->offset) / (1 + to->offset), to->gamma); - to->B <= to->transitioninv ? to->B * to->slope : pow((to->B + to->offset) / (1 + to->offset), to->gamma); - break; - case LIBCOLOUR_ENCODING_TYPE_CUSTOM: - to->R = (to->to_decoded_red)(to->R); - to->G = (to->to_decoded_green)(to->G); - to->B = (to->to_decoded_blue)(to->B); - break; - default: - fprintf(stderr, "libcolour: invalid encoding type\n"); - abort(); - } - } - } -} - - -static void ciexyz_to_srgb(const libcolour_ciexyz_t* restrict from, libcolour_srgb_t* restrict to) -{ - double X = from->X, Y = from->Y, Z = from->Z; - to->R = 3.240450 * X + -1.537140 * Y + -0.4985320 * Z; - to->G = -0.969266 * X + 1.876010 * Y + 0.0415561 * Z; - to->B = 0.0556434 * X + -0.204026 * Y + 1.0572300 * Z; -} - -static void srgb_to_srgb(const libcolour_srgb_t* restrict from, libcolour_srgb_t* restrict to) -{ - if (from->with_gamma == to->with_gamma) { - *to = *from; - } else if (to->with_gamma) { - to->R = libcolour_srgb_encode(from->R); - to->G = libcolour_srgb_encode(from->G); - to->B = libcolour_srgb_encode(from->B); - } else { - to->R = libcolour_srgb_decode(from->R); - to->G = libcolour_srgb_decode(from->G); - to->B = libcolour_srgb_decode(from->B); - } -} - -static void yiq_to_srgb(const libcolour_yiq_t* restrict from, libcolour_srgb_t* restrict to) -{ - double Y = from->Y, I = from->I, Q = from->Q; - to->R = Y + I * 0.956 + Q * 0.621; - to->G = Y - I * 0.272 - Q * 0.647; - to->B = Y - I * 1.106 + Q * 1.703; -} - -static void ydbdr_to_srgb(const libcolour_ydbdr_t* restrict from, libcolour_srgb_t* restrict to) -{ - double Y = from->Y, Db = from->Db, Dr = from->Dr; - to->R = Y + Db * 0.000092303716148 - Dr * 0.525912630661865; - to->G = Y - Db * 0.129132898890509 + Dr * 0.267899328207599; - to->B = Y + Db * 0.664679059978955 - Dr * 0.000079202543533; -} - -static void ypbpr_to_srgb(const libcolour_ypbpr_t* restrict from, libcolour_srgb_t* restrict to) -{ - double Y = from->Y, Pb = from->Pb, Pr = from->Pr; - to->R = Pr + Y; - to->B = Pb + Y; - to->G = (Y - to->R * 0.2126 - to->B * 0.0722) / 0.7152; -} - -static void ycgco_to_srgb(const libcolour_ycgco_t* restrict from, libcolour_srgb_t* restrict to) -{ - double Y = from->Y, Cg = from->Cg, Co = from->Co; - to->R = Y - Cg + Co; - to->G = Y + Cg; - to->B = Y - Cg - Co; -} - -static void other_to_srgb(const libcolour_colour_t* restrict from, libcolour_srgb_t* restrict to) -{ - libcolour_ciexyz_t tmp; - tmp.model = LIBCOLOUR_CIEXYZ; - to_ciexyz(from, &tmp); - ciexyz_to_srgb(&tmp, to); -} - -static void to_srgb(const libcolour_colour_t* restrict from, libcolour_srgb_t* restrict to) -{ - libcolour_srgb_t tmp; - switch (from->model) { - case LIBCOLOUR_CIEXYZ: - ciexyz_to_srgb(&from->ciexyz, to); - break; - case LIBCOLOUR_SRGB: - srgb_to_srgb(&from->srgb, to); - return; - case LIBCOLOUR_YIQ: - yiq_to_srgb(&from->yiq, to); - break; - case LIBCOLOUR_YDBDR: - ydbdr_to_srgb(&from->ydbdr, to); - break; - case LIBCOLOUR_YPBPR: - ypbpr_to_srgb(&from->ypbpr, to); - break; - case LIBCOLOUR_YCGCO: - ycgco_to_srgb(&from->ycgco, to); - break; - default: - other_to_srgb(from, to); - break; - } - if (to->with_gamma) { - tmp = *to; - tmp.with_gamma = 0; - srgb_to_srgb(&tmp, to); - } -} - - -static void ciexyz_to_ciexyy(const libcolour_ciexyz_t* restrict from, libcolour_ciexyy_t* restrict to) -{ - double X = from->X, Y = from->Y, Z = from->Z; - double s = X + Y + Z; - to->x = X / s; - to->y = Y / s; - to->Y = Y; - if (WASDIV0(to->x) || WASDIV0(to->y)) - to->x = to->y = 0; -} - -static void other_to_ciexyy(const libcolour_colour_t* restrict from, libcolour_ciexyy_t* restrict to) -{ - libcolour_ciexyz_t tmp; - tmp.model = LIBCOLOUR_CIEXYZ; - to_ciexyz(from, &tmp); - ciexyz_to_ciexyy(&tmp, to); -} - -static void srgb_to_ciexyy(const libcolour_srgb_t* restrict from, libcolour_ciexyy_t* restrict to) -{ - libcolour_srgb_t tmp; - tmp.model = LIBCOLOUR_SRGB; - if (from->with_gamma) { - tmp.with_gamma = 0; - to_srgb((const libcolour_colour_t*)from, &tmp); - } else { - tmp = *from; - } - if (tmp.R == 0 && tmp.G == 0 && tmp.B == 0) { - to->x = 0.31272660439158; - to->y = 0.32902315240275; - to->Y = 0; - } else { - other_to_ciexyy((const libcolour_colour_t*)&tmp, to); - } -} - -static void to_ciexyy(const libcolour_colour_t* restrict from, libcolour_ciexyy_t* restrict to) -{ - switch (from->model) { - case LIBCOLOUR_CIEXYY: - *to = from->ciexyy; - return; - case LIBCOLOUR_CIEXYZ: - ciexyz_to_ciexyy(&from->ciexyz, to); - return; - case LIBCOLOUR_SRGB: - srgb_to_ciexyy(&from->srgb, to); - return; - default: - other_to_ciexyy(from, to); - return; - } -} - - -static void rgb_to_ciexyz(const libcolour_rgb_t* restrict from, libcolour_ciexyz_t* restrict to) -{ - libcolour_rgb_t tmp; - double R, G, B; - if (from->with_gamma) { - tmp = *from; - tmp.with_gamma = 0; - to_rgb((const libcolour_colour_t*)from, &tmp); - R = tmp.R, G = tmp.G, B = tmp.B; - } else { - R = from->R, G = from->G, B = from->B; - } - to->X = from->M[0][0] * R + from->M[0][1] * G + from->M[0][2] * B; - to->Y = from->M[1][0] * R + from->M[1][1] * G + from->M[1][2] * B; - to->Z = from->M[2][0] * R + from->M[2][1] * G + from->M[2][2] * B; -} - -static void srgb_to_ciexyz(const libcolour_srgb_t* restrict from, libcolour_ciexyz_t* restrict to) -{ - libcolour_srgb_t tmp; - double R, G, B; - if (from->with_gamma) { - tmp.model = LIBCOLOUR_SRGB; - tmp.with_gamma = 0; - to_srgb((const libcolour_colour_t*)from, &tmp); - R = tmp.R, G = tmp.G, B = tmp.B; - } else { - R = from->R, G = from->G, B = from->B; - } - to->X = 0.4124564 * R + 0.3575761 * G + 0.1804375 * B; - to->Y = 0.2126729 * R + 0.7151522 * G + 0.0721750 * B; - to->Z = 0.0193339 * R + 0.1191920 * G + 0.9503041 * B; -} - -static void ciexyy_to_ciexyz(const libcolour_ciexyy_t* restrict from, libcolour_ciexyz_t* restrict to) -{ - double x = from->x, y = from->y, Y = from->Y; - double Yy = Y / y; - if (WASDIV0(Yy)) { - to->X = to->Y = to->Z = Y; - } else { - to->X = x * Yy; - to->Y = Y; - to->Z = (1 - x - y) * Yy; - } -} - -static inline double cielab_finv(double t) -{ - return (t > 6. / 29.) ? t * t * t : (t - 4. / 29.) * 108 / 841; -} - -static void cielab_to_ciexyz(const libcolour_cielab_t* restrict from, libcolour_ciexyz_t* restrict to) -{ - double L = from->L, a = from->a, b = from->b; - to->Y = (L + 16) / 116; - to->X = to->Y + a / 500; - to->Z = to->Y - b / 200; - to->X = cielab_finv(to->X) * 0.95047; - to->Y = cielab_finv(to->Y) * 1.08883; - to->Z = cielab_finv(to->Z); -} - -static void cieluv_to_ciexyz(const libcolour_cieluv_t* restrict from, libcolour_ciexyz_t* restrict to) -{ - double X = from->white.X, Y = from->white.Y, L = from->L, L13 = from->L * 13; - double t = X + 15 * Y + 3 * from->white.Z; - double u = from->u / L13 + 4 * X / t; - double v = from->v / L13 + 9 * Y / t; - if (L <= 8) { - Y *= L * 27 / 24389; - } else { - L = (L + 16) / 116; - Y *= L * L * L; - } - to->X = 2.25 * Y * u / v; - to->Y = Y; - to->Z = Y * (3 / v - 0.75 * u / v - 5); -} - -static void cielchuv_to_ciexyz(const libcolour_cielchuv_t* restrict from, libcolour_ciexyz_t* restrict to) -{ - libcolour_cieluv_t tmp; - tmp.model = LIBCOLOUR_CIELUV; - tmp.white = from->white; - to_cieluv((const libcolour_colour_t*)from, &tmp); - cieluv_to_ciexyz(&tmp, to); -} - -static void yuv_to_ciexyz(const libcolour_yuv_t* restrict from, libcolour_ciexyz_t* restrict to) -{ - libcolour_ydbdr_t tmp; - tmp.model = LIBCOLOUR_YDBDR; - to_ydbdr((const libcolour_colour_t*)from, &tmp); - to_ciexyz((const libcolour_colour_t*)&tmp, to); -} - -static void cie1960ucs_to_ciexyz(const libcolour_cie1960ucs_t* restrict from, libcolour_ciexyz_t* restrict to) -{ - double u = from->u, v = from->v, Y = from->Y; - to->X = 1.5 * Y * u / v; - to->Y = Y; - to->Z = (4 * Y - Y * u - 10 * Y * v) / (2 * v); -} - -static void cieuvw_to_ciexyz(const libcolour_cieuvw_t* restrict from, libcolour_ciexyz_t* restrict to) -{ - libcolour_cie1960ucs_t tmp; - tmp.model = LIBCOLOUR_CIE1960UCS; - to_cie1960ucs((const libcolour_colour_t*)from, &tmp); - cie1960ucs_to_ciexyz(&tmp, to); -} - -static void other_to_ciexyz(const libcolour_colour_t* restrict from, libcolour_ciexyz_t* restrict to) -{ - libcolour_srgb_t tmp; - tmp.model = LIBCOLOUR_SRGB; - tmp.with_gamma = 0; - to_srgb(from, &tmp); - srgb_to_ciexyz(&tmp, to); -} - -static void to_ciexyz(const libcolour_colour_t* restrict from, libcolour_ciexyz_t* restrict to) -{ - switch (from->model) { - case LIBCOLOUR_RGB: - rgb_to_ciexyz(&from->rgb, to); - return; - case LIBCOLOUR_SRGB: - srgb_to_ciexyz(&from->srgb, to); - return; - case LIBCOLOUR_CIEXYY: - ciexyy_to_ciexyz(&from->ciexyy, to); - return; - case LIBCOLOUR_CIEXYZ: - *to = from->ciexyz; - return; - case LIBCOLOUR_CIELAB: - cielab_to_ciexyz(&from->cielab, to); - return; - case LIBCOLOUR_CIELUV: - cieluv_to_ciexyz(&from->cieluv, to); - return; - case LIBCOLOUR_CIELCHUV: - cielchuv_to_ciexyz(&from->cielchuv, to); - return; - case LIBCOLOUR_YUV: - yuv_to_ciexyz(&from->yuv, to); - return; - case LIBCOLOUR_CIE1960UCS: - cie1960ucs_to_ciexyz(&from->cie1960ucs, to); - return; - case LIBCOLOUR_CIEUVW: - cieuvw_to_ciexyz(&from->cieuvw, to); - return; - default: - other_to_ciexyz(from, to); - return; - } -} - - -static inline double cielab_f(double t) -{ - return (t > 216. / 24389.) ? cbrt(t) : t * 841. / 108. + 4. / 29.; -} - -static void ciexyz_to_cielab(const libcolour_ciexyz_t* restrict from, libcolour_cielab_t* restrict to) -{ - double X = from->X, Y = from->Y, Z = from->Z; - X /= 0.95047; - Y /= 1.08883; - Y = cielab_f(Y); - to->L = 116 * Y - 16; - to->a = 500 * (cielab_f(X) - Y); - to->b = 200 * (Y - cielab_f(Z)); -} - -static void other_to_cielab(const libcolour_colour_t* restrict from, libcolour_cielab_t* restrict to) -{ - libcolour_ciexyz_t tmp; - tmp.model = LIBCOLOUR_CIEXYZ; - to_ciexyz(from, &tmp); - ciexyz_to_cielab(&tmp, to); -} - -static void to_cielab(const libcolour_colour_t* restrict from, libcolour_cielab_t* restrict to) -{ - switch (from->model) { - case LIBCOLOUR_CIEXYZ: - ciexyz_to_cielab(&from->ciexyz, to); - return; - case LIBCOLOUR_CIELAB: - *to = from->cielab; - return; - default: - other_to_cielab(from, to); - return; - } -} - - -static void ciexyz_to_cieluv(const libcolour_ciexyz_t* restrict from, libcolour_cieluv_t* restrict to) -{ - double t, u, v, y, y2; - t = to->white.X + 15 * to->white.Y + 3 * to->white.Z; - u = 4 * to->white.X / t; - v = 9 * to->white.Y / t; - t = from->X + 15 * from->Y + 3 * from->Z; - u = 4 * from->X / t - u; - v = 9 * from->Y / t - v; - y = from->Y / to->white.Y; - y2 = y * 24389; - y = y2 <= 216 ? y2 / 27 : cbrt(y) * 116 - 16; - to->L = y; - y *= 13; - to->u = u * y; - to->v = v * y; -} - -static void cielchuv_to_cieluv(const libcolour_cielchuv_t* restrict from, libcolour_cieluv_t* restrict to) -{ - libcolour_ciexyz_t tmp; - libcolour_cielchuv_t tmp2; - double L, C, h; - if (to->white.X != from->white.X || to->white.Y != from->white.Y || to->white.Z != from->white.Z) { - tmp.model = LIBCOLOUR_CIEXYZ; - tmp2.model = LIBCOLOUR_CIELCHUV; - tmp2.white = to->white; - to_ciexyz((const libcolour_colour_t*)from, &tmp); - to_cielchuv((const libcolour_colour_t*)&tmp, &tmp2); - L = tmp2.L, C = tmp2.C, h = tmp2.h; - } else { - L = from->L, C = from->C, h = from->h; - } - to->L = L; - to->u = C * cos(h); - to->v = C * sin(h); -} - -static void other_to_cieluv(const libcolour_colour_t* restrict from, libcolour_cieluv_t* restrict to) -{ - libcolour_ciexyz_t tmp; - tmp.model = LIBCOLOUR_CIEXYZ; - to_ciexyz(from, &tmp); - ciexyz_to_cieluv(&tmp, to); -} - -static void to_cieluv(const libcolour_colour_t* restrict from, libcolour_cieluv_t* restrict to) -{ - switch (from->model) { - case LIBCOLOUR_CIEXYZ: - ciexyz_to_cieluv(&from->ciexyz, to); - return; - case LIBCOLOUR_CIELCHUV: - cielchuv_to_cieluv(&from->cielchuv, to); - return; - case LIBCOLOUR_CIELUV: - if (to->white.X == from->cieluv.white.X && - to->white.Y == from->cieluv.white.Y && - to->white.Z == from->cieluv.white.Z) { - *to = from->cieluv; - return; - } - /* fall through */ - default: - other_to_cieluv(from, to); - return; - } -} - - -static void cieluv_to_cielchuv(const libcolour_cieluv_t* restrict from, libcolour_cielchuv_t* restrict to) -{ - libcolour_cieluv_t tmp; - double L, u, v; - if (to->white.X != from->white.X || to->white.Y != from->white.Y || to->white.Z != from->white.Z) { - tmp.model = LIBCOLOUR_CIELUV; - tmp.white = to->white; - to_cieluv((const libcolour_colour_t*)from, &tmp); - L = tmp.L, u = tmp.u, v = tmp.v; - } else { - L = from->L, u = from->u, v = from->v; - } - to->L = L; - to->C = sqrt(u * u + v * v); - to->h = atan2(v, u); -} - -static void other_to_cielchuv(const libcolour_colour_t* restrict from, libcolour_cielchuv_t* restrict to) -{ - libcolour_cieluv_t tmp; - tmp.model = LIBCOLOUR_CIELUV; - tmp.white = to->white; - to_cieluv(from, &tmp); - cieluv_to_cielchuv(&tmp, to); -} - -static void to_cielchuv(const libcolour_colour_t* restrict from, libcolour_cielchuv_t* restrict to) -{ - switch (from->model) { - case LIBCOLOUR_CIELUV: - cieluv_to_cielchuv(&from->cieluv, to); - return; - case LIBCOLOUR_CIELCHUV: - if (to->white.X == from->cielchuv.white.X && - to->white.Y == from->cielchuv.white.Y && - to->white.Z == from->cielchuv.white.Z) { - *to = from->cielchuv; - return; - } - /* fall through */ - default: - other_to_cielchuv(from, to); - return; - } -} - - -static void to_yiq(const libcolour_colour_t* restrict from, libcolour_yiq_t* restrict to) -{ - /* TODO to_yiq: add direct conversion from and to CIE XYZ and use it as the default intermediary */ - double r, g, b; - libcolour_colour_t tmp = *from; - switch (from->model) { - case LIBCOLOUR_YIQ: - *to = from->yiq; - return; - default: - tmp.model = LIBCOLOUR_SRGB; - tmp.srgb.with_gamma = 0; - to_srgb(from, &tmp.srgb); - /* fall through */ - case LIBCOLOUR_SRGB: - if (tmp.srgb.with_gamma) { - tmp.srgb.with_gamma = 0; - to_srgb(from, &tmp.srgb); - } - r = tmp.srgb.R; - g = tmp.srgb.G; - b = tmp.srgb.B; - to->Y = r * 0.29893602129377540 + g * 0.5870430744511212 + b * 0.11402090425510336; - to->I = r * 0.59594574307079930 - g * 0.2743886357457892 - b * 0.32155710732501010; - to->Q = r * 0.21149734030682846 - g * 0.5229106903029739 + b * 0.31141334999614540; - return; - } -} - - -static void to_ydbdr(const libcolour_colour_t* restrict from, libcolour_ydbdr_t* restrict to) -{ - /* TODO to_ydbdr: add direct conversion from and to CIE XYZ and use it as the default intermediary */ - double r, g, b; - libcolour_colour_t tmp = *from; - switch (from->model) { - case LIBCOLOUR_YDBDR: - *to = from->ydbdr; - return; - case LIBCOLOUR_YUV: - to->Y = tmp.yuv.Y; - to->Db = tmp.yuv.U * 3.069; - to->Dr = -tmp.yuv.V * 2.169; - return; - default: - tmp.model = LIBCOLOUR_SRGB; - tmp.srgb.with_gamma = 0; - to_srgb(from, &tmp.srgb); - /* fall through */ - case LIBCOLOUR_SRGB: - if (tmp.srgb.with_gamma) { - tmp.srgb.with_gamma = 0; - to_srgb(from, &tmp.srgb); - } - r = tmp.srgb.R; - g = tmp.srgb.G; - b = tmp.srgb.B; - to->Y = r * 0.299 + g * 0.587 + b * 0.114; - to->Db = -r * 0.450 - g * 0.883 + b * 1.333; - to->Dr = -r * 1.333 + g * 1.116 + b * 0.217; - return; - } -} - - -static void to_yuv(const libcolour_colour_t* restrict from, libcolour_yuv_t* restrict to) -{ - /* TODO to_yuv: add direct conversion from and to CIE XYZ and use it as the default intermediary */ - /* TODO to_yub: add direct conversion from and to sRGB */ - libcolour_colour_t tmp = *from; - switch (from->model) { - case LIBCOLOUR_YUV: - *to = from->yuv; - return; - default: - tmp.model = LIBCOLOUR_YDBDR; - to_ydbdr(from, &tmp.ydbdr); - /* fall through */ - case LIBCOLOUR_YDBDR: - to->Y = tmp.ydbdr.Y; - to->U = tmp.ydbdr.Db / 3.069; - to->V = -tmp.ydbdr.Dr / 2.169; - return; - } -} - - -static void to_ypbpr(const libcolour_colour_t* restrict from, libcolour_ypbpr_t* restrict to) -{ - libcolour_colour_t tmp = *from; - switch (from->model) { - case LIBCOLOUR_YPBPR: - *to = from->ypbpr; - return; - default: - tmp.model = LIBCOLOUR_SRGB; - tmp.srgb.with_gamma = 0; - to_srgb(from, &tmp.srgb); - /* fall through */ - case LIBCOLOUR_SRGB: - if (tmp.srgb.with_gamma) { - tmp.srgb.with_gamma = 0; - to_srgb(from, &tmp.srgb); - } - to->Y = tmp.srgb.R * 0.2126 + tmp.srgb.G * 0.7152 + tmp.srgb.B * 0.0722; - to->Pb = tmp.srgb.B - to->Y; - to->Pr = tmp.srgb.R - to->Y; - return; - } -} - - -static void to_ycgco(const libcolour_colour_t* restrict from, libcolour_ycgco_t* restrict to) -{ - /* TODO to_ycgco: add direct conversion from and to CIE XYZ and use it as the default intermediary */ - libcolour_colour_t tmp = *from; - switch (from->model) { - case LIBCOLOUR_YCGCO: - *to = from->ycgco; - return; - default: - tmp.model = LIBCOLOUR_SRGB; - tmp.srgb.with_gamma = 0; - to_srgb(from, &tmp.srgb); - /* fall through */ - case LIBCOLOUR_SRGB: - if (tmp.srgb.with_gamma) { - tmp.srgb.with_gamma = 0; - to_srgb(from, &tmp.srgb); - } - to->Y = tmp.srgb.R / 4 + tmp.srgb.G / 2 + tmp.srgb.B / 4; - to->Cg = -tmp.srgb.R / 4 + tmp.srgb.G / 2 - tmp.srgb.B / 4; - to->Co = tmp.srgb.R / 2 - tmp.srgb.B / 2; - return; - } -} - - -static void to_cie1960ucs(const libcolour_colour_t* restrict from, libcolour_cie1960ucs_t* restrict to) -{ - libcolour_colour_t tmp = *from; - double u, v, w, y; - switch (from->model) { - case LIBCOLOUR_CIE1960UCS: - *to = from->cie1960ucs; - return; - case LIBCOLOUR_CIEUVW: - u = from->cieuvw.U, v = from->cieuvw.V, w = from->cieuvw.W; - y = (w + 17) / 25; - y *= y * y; - w *= 13; - to->u = u / w + from->cieuvw.u0; - to->v = v / w + from->cieuvw.v0; - to->Y = y; - return; - default: - tmp.model = LIBCOLOUR_CIEXYZ; - to_ciexyz(from, &tmp.ciexyz); - /* fall through */ - case LIBCOLOUR_CIEXYZ: - w = tmp.ciexyz.X + 15 * tmp.ciexyz.Y + 3 * tmp.ciexyz.Z; - to->u = 4 * tmp.ciexyz.X / w; - to->v = 6 * tmp.ciexyz.Y / w; - to->Y = tmp.ciexyz.Y; - return; - } -} - - -static void to_cieuvw(const libcolour_colour_t* restrict from, libcolour_cieuvw_t* restrict to) -{ - double U, V, W, w; - libcolour_colour_t tmp = *from; - switch (from->model) { - case LIBCOLOUR_CIEUVW: - U = from->cieuvw.U, V = from->cieuvw.V, W = from->cieuvw.W; - w = W * 13; - U += w * (from->cieuvw.u0 - to->u0); - V += w * (from->cieuvw.v0 - to->v0); - to->U = U, to->V = V, to->W = W; - return; - default: - tmp.model = LIBCOLOUR_CIE1960UCS; - to_cie1960ucs(from, &tmp.cie1960ucs); - /* fall through */ - case LIBCOLOUR_CIE1960UCS: - U = tmp.cie1960ucs.u, V = tmp.cie1960ucs.v, W = tmp.cie1960ucs.Y; - W = 25 * cbrt(W) - 17; - w = W * 13; - to->U = w * (U - to->u0); - to->V = w * (V - to->v0); - to->W = W; - return; - } -} - - - -int libcolour_convert(const libcolour_colour_t* restrict from, libcolour_colour_t* restrict to) -{ -#define X(C, T) 1 + - if (from->model < 0 || from->model > LIBCOLOUR_LIST_MODELS 0) { -#undef X - errno = EINVAL; - return -1; - } - switch (to->model) { - case LIBCOLOUR_RGB: - to_rgb(from, &to->rgb); - break; - case LIBCOLOUR_SRGB: - to_srgb(from, &to->srgb); - break; - case LIBCOLOUR_CIEXYY: - to_ciexyy(from, &to->ciexyy); - break; - case LIBCOLOUR_CIEXYZ: - to_ciexyz(from, &to->ciexyz); - break; - case LIBCOLOUR_CIELAB: - to_cielab(from, &to->cielab); - break; - case LIBCOLOUR_CIELUV: - to_cieluv(from, &to->cieluv); - break; - case LIBCOLOUR_CIELCHUV: - to_cielchuv(from, &to->cielchuv); - break; - case LIBCOLOUR_YIQ: - to_yiq(from, &to->yiq); - break; - case LIBCOLOUR_YDBDR: - to_ydbdr(from, &to->ydbdr); - break; - case LIBCOLOUR_YUV: - to_yuv(from, &to->yuv); - break; - case LIBCOLOUR_YPBPR: - to_ypbpr(from, &to->ypbpr); - break; - case LIBCOLOUR_YCGCO: - to_ycgco(from, &to->ycgco); - break; - case LIBCOLOUR_CIE1960UCS: - to_cie1960ucs(from, &to->cie1960ucs); - break; - case LIBCOLOUR_CIEUVW: - to_cieuvw(from, &to->cieuvw); - break; - default: - errno = EINVAL; - return -1; - } - return 0; -} - - double libcolour_srgb_encode(double x) { return x <= 0.0031306684425217108 ? 12.92 * x : 1.055 * pow(x, 1 / 2.4) - 0.055; |