/**
* Copyright © 2016 Mattias Andrée <maandree@member.fsf.org>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "libclut.h"
#include <errno.h>
/**
* Convert one component from [0, 1] linear sRGB to [0, 1] sRGB.
*
* @param c The linear sRGB value.
* @return Corresponding sRGB value.
*/
double (libclut_model_linear_to_standard1)(double c)
{
return libclut_model_linear_to_standard1(c);
}
/**
* Convert [0, 1] linear sRGB to [0, 1] sRGB.
*
* @param r Pointer to the linear red component,
* and output parameter for the red component.
* @param g Pointer to the linear green component,
* and output parameter for the green component.
* @param b Pointer to the linear blue component,
* and output parameter for the blue component.
*/
void (libclut_model_linear_to_standard)(double* r, double* g, double* b)
{
libclut_model_linear_to_standard(r, g, b);
}
/**
* Convert one component from [0, 1] sRGB to [0, 1] linear sRGB.
*
* @param c The sRGB value.
* @return Corresponding linear sRGB value.
*/
double (libclut_model_standard_to_linear1)(double c)
{
return libclut_model_standard_to_linear1(c);
}
/**
* Convert [0, 1] sRGB to [0, 1] linear sRGB.
*
* @param r Pointer to the red component, and output
* parameter for the linear red component.
* @param g Pointer to the green component, and output
* parameter for the linear green component.
* @param b Pointer to the blue component, and output
* parameter for the linear blue component.
*/
void (libclut_model_standard_to_linear)(double* r, double* g, double* b)
{
libclut_model_standard_to_linear(r, g, b);
}
/**
* Convert CIE xyY to CIE XYZ.
*
* @param x The x parameter.
* @param y The y parameter.
* @param Y The Y parameter. This is also the Y (middle) parameter for the CIE XYZ colour.
* @param X Output parameter for the X parameter.
* @param Z Output parameter for the Z parameter.
*/
void (libclut_model_ciexyy_to_ciexyz)(double x, double y, double Y, double* X, double* Z)
{
libclut_model_ciexyy_to_ciexyz(x, y, Y, X, Z);
}
/**
* Convert CIE XYZ to CIE xyY.
*
* @param X The X parameter.
* @param Y The Y parameter. This is also the Y (last) parameter for the CIE xyY colour.
* @param Z The Z parameter.
* @param x Output parameter for the x parameter.
* @param y Output parameter for the y parameter.
*/
void (libclut_model_ciexyz_to_ciexyy)(double X, double Y, double Z, double* x, double* y)
{
libclut_model_ciexyz_to_ciexyy(X, Y, Z, x, y);
}
/**
* Convert CIE XYZ to [0, 1] linear sRGB.
*
* @param X The X parameter.
* @param Y The Y parameter.
* @param Z The Z parameter.
* @param r Output parameter for the red component.
* @param g Output parameter for the green component.
* @param b Output parameter for the blue component.
*/
void (libclut_model_ciexyz_to_linear)(double X, double Y, double Z, double* r, double* g, double* b)
{
libclut_model_ciexyz_to_linear(X, Y, Z, r, g, b);
}
/**
* Convert [0, 1] linear sRGB to CIE XYZ.
*
* @param r The red component.
* @param g The green component.
* @param b The blue component.
* @param X Output parameter for the X parameter.
* @param Y Output parameter for the Y parameter.
* @param Z Output parameter for the Z parameter.
*/
void (libclut_model_linear_to_ciexyz)(double r, double g, double b, double* X, double* Y, double* Z)
{
libclut_model_linear_to_ciexyz(r, g, b, X, Y, Z);
}
/**
* Convert [0, 1] linear sRGB to CIE xyY.
*
* @param r The red component.
* @param g The green component.
* @param b The blue component.
* @param x Output parameter for the x parameter.
* @param y Output parameter for the y parameter.
* @param Y Output parameter for the Y parameter.
*/
void (libclut_model_srgb_to_ciexyy)(double r, double g, double b, double* x, double* y, double* Y)
{
libclut_model_srgb_to_ciexyy(r, g, b, x, y, Y);
}
/**
* Convert CIE xyY to [0, 1] sRGB.
*
* @param x The x parameter.
* @param y The y parameter.
* @param Y The Y parameter.
* @param r Output parameter for the red component.
* @param g Output parameter for the green component.
* @param b Output parameter for the blue component.
*/
void (libclut_model_ciexyy_to_srgb)(double x, double y, double Y, double* r, double* g, double* b)
{
libclut_model_ciexyy_to_srgb(x, y, Y, r, g, b);
}
/**
* Convert from CIE XYZ to CIE L*a*b*.
*
* @param X The X parameter.
* @param Y The Y parameter.
* @param Z The Z parameter.
* @param L Output parameter for the L* component.
* @param a Output parameter for the a* component.
* @param b Output parameter for the b* component.
*/
void (libclut_model_ciexyz_to_cielab)(double X, double Y, double Z, double* L, double* a, double* b)
{
libclut_model_ciexyz_to_cielab(X, Y, Z, L, a, b);
}
/**
* Convert from CIE L*a*b* to CIE XYZ.
*
* @param L The L* component.
* @param a The a* component.
* @param b The b* component.
* @param X Output parameter for the X parameter.
* @param Y Output parameter for the Y parameter.
* @param Z Output parameter for the Z parameter.
*/
void (libclut_model_cielab_to_ciexyz)(double L, double a, double b, double* X, double* Y, double* Z)
{
libclut_model_cielab_to_ciexyz(L, a, b, X, Y, Z);
}
/**
* Convert from CIE XYZ to CIE L*u*v*.
*
* @param X The X parameter.
* @param Y The Y parameter.
* @param Z The Z parameter.
* @param Xn The X component of the specified white object (white point).
* @param Yn The Y component of the specified white object (white point).
* @param Zn The Z component of the specified white object (white point).
* @param L Output parameter for the L* component.
* @param u Output parameter for the u* component.
* @param v Output parameter for the v* component.
*/
void (libclut_model_ciexyz_to_cieluv)(double X, double Y, double Z, double Xn, double Yn, double Zn,
double* L, double* u, double* v)
{
libclut_model_ciexyz_to_cieluv(X, Y, Z, Xn, Yn, Zn, L, u, v);
}
/**
* Convert from CIE L*u*v* to CIE XYZ.
*
* @param L The L* component.
* @param u The u* component.
* @param v The v* component.
* @param Xn The X component of the specified white object (white point).
* @param Yn The Y component of the specified white object (white point).
* @param Zn The Z component of the specified white object (white point).
* @param X Output parameter for the X parameter.
* @param Y Output parameter for the Y parameter.
* @param Z Output parameter for the Z parameter.
*/
void (libclut_model_cieluv_to_ciexyz)(double L, double u, double v, double Xn, double Yn, double Zn,
double* X, double* Y, double* Z)
{
libclut_model_cieluv_to_ciexyz(L, u, v, Xn, Yn, Zn, X, Y, Z);
}
/**
* Convert from CIELCh to CIE L*u*v*.
*
* @param L The L* component.
* @param C The C*_uv component.
* @param h The h_uv component.
* @param u Output parameter for the u* parameter.
* @param v Output parameter for the v* parameter.
*/
void (libclut_model_cielch_to_cieluv)(double C, double h, double* u, double* v)
{
libclut_model_cielch_to_cieluv(C, h, u, v);
}
/**
* Convert from CIE L*u*v* to CIELCh.
*
* @param L The L* component.
* @param u The u* component.
* @param v The v* component.
* @param C Output parameter for the C*_uv parameter.
* @param h Output parameter for the h_uv parameter.
*/
void (libclut_model_cieluv_to_cielch)(double u, double v, double* C, double* h)
{
libclut_model_cieluv_to_cielch(u, v, C, h);
}
/**
* Convert from sRGB to YIQ.
*
* @param r The R component.
* @param g The G component.
* @param b The B component.
* @param y Output parameter for the Y parameter.
* @param i Output parameter for the I parameter.
* @param q Output parameter for the Q parameter.
*/
void (libclut_model_srgb_to_yiq)(double r, double g, double b, double* y, double* i, double* q)
{
libclut_model_srgb_to_yiq(r, g, b, y, i, q);
}
/**
* Convert from YIQ to sRGB.
*
* @param y The Y component.
* @param i The I component.
* @param q The Q component.
* @param r Output parameter for the R parameter.
* @param g Output parameter for the G parameter.
* @param b Output parameter for the B parameter.
*/
void (libclut_model_yiq_to_srgb)(double y, double i, double q, double* r, double* g, double* b)
{
libclut_model_yiq_to_srgb(y, i, q, r, g, b);
}
/**
* Convert from sRGB to YDbDr.
*
* @param r The R component.
* @param g The G component.
* @param b The B component.
* @param y Output parameter for the Y parameter.
* @param db Output parameter for the Db parameter.
* @param dr Output parameter for the Dr parameter.
*/
void (libclut_model_srgb_to_ydbdr)(double r, double g, double b, double* y, double* db, double* dr)
{
libclut_model_srgb_to_ydbdr(r, g, b, y, db, dr);
}
/**
* Convert from YDbDr to sRGB.
*
* @param y The Y component.
* @param db The Db component.
* @param dr The Dr component.
* @param r Output parameter for the R parameter.
* @param g Output parameter for the G parameter.
* @param b Output parameter for the B parameter.
*/
void (libclut_model_ydbdr_to_srgb)(double y, double db, double dr, double* r, double* g, double* b)
{
libclut_model_ydbdr_to_srgb(y, db, dr, r, g, b);
}
/**
* Convert from YUV to YDbDr.
*
* @param u The U component.
* @param v The V component.
* @param db Output parameter for the Db parameter.
* @param dr Output parameter for the Dr parameter.
*/
void (libclut_model_yuv_to_ydbdr)(double u, double v, double* db, double* dr)
{
libclut_model_yuv_to_ydbdr(u, v, db, dr);
}
/**
* Convert from YDbDr to YUV.
*
* @param db The Db component.
* @param dr The Dr component.
* @param u Output parameter for the U parameter.
* @param v Output parameter for the V parameter.
*/
void (libclut_model_ydbdr_to_yuv)(double db, double dr, double* u, double* v)
{
libclut_model_ydbdr_to_yuv(db, dr, u, v);
}
/**
* Convert from sRGB to YPbPr.
*
* @param r The R component.
* @param g The G component.
* @param b The B component.
* @param y Output parameter for the Y parameter.
* @param pb Output parameter for the Pb parameter.
* @param pr Output parameter for the Pr parameter.
*/
void (libclut_model_srgb_to_ypbpr)(double r, double g, double b, double* y, double* pb, double* pr)
{
libclut_model_srgb_to_ypbpr(r, g, b, y, pb, pr);
}
/**
* Convert from YPbPr to sRGB.
*
* @param y The Y component.
* @param pb The Pb component.
* @param pr The Pr component.
* @param r Output parameter for the R parameter.
* @param g Output parameter for the G parameter.
* @param b Output parameter for the B parameter.
*/
void (libclut_model_ypbpr_to_srgb)(double y, double pb, double pr, double* r, double* g, double* b)
{
libclut_model_ypbpr_to_srgb(y, pb, pr, r, g, b);
}
/**
* Convert from sRGB to YCgCo.
*
* @param r The R component.
* @param g The G component.
* @param b The B component.
* @param y Output parameter for the Y parameter.
* @param cg Output parameter for the Cg parameter.
* @param co Output parameter for the Co parameter.
*/
void (libclut_model_srgb_to_ycgco)(double r, double g, double b, double* y, double* cg, double* co)
{
libclut_model_srgb_to_ycgco(r, g, b, y, cg, co);
}
/**
* Convert from YCgCo to sRGB.
*
* @param y The Y component.
* @param cg The Cg component.
* @param co The Co component.
* @param r Output parameter for the R parameter.
* @param g Output parameter for the G parameter.
* @param b Output parameter for the B parameter.
*/
void (libclut_model_ycgco_to_srgb)(double y, double cg, double co, double* r, double* g, double* b)
{
libclut_model_ycgco_to_srgb(y, cg, co, r, g, b);
}
/**
* Convert from CIE 1960 UCS to CIE XYZ.
*
* @param u The u component.
* @param v The v component.
* @param Y The Y component.
* @param x Output parameter for the X parameter.
* @param y Output parameter for the Y parameter.
* @param z Output parameter for the Z parameter.
*/
void (libclut_model_cie_1960_ucs_to_ciexyz)(double u, double v, double Y, double* x, double* y, double* z)
{
libclut_model_cie_1960_ucs_to_ciexyz(u, v, Y, x, y, z);
}
/**
* Convert from CIE XYZ to CIE 1960 UCS.
*
* @param x The X component.
* @param y The Y component.
* @param z The Z component.
* @param u Output parameter for the u parameter.
* @param v Output parameter for the v parameter.
* @param Y Output parameter for the Y parameter.
*/
void (libclut_model_ciexyz_to_cie_1960_ucs)(double x, double y, double z, double* u, double* v, double* Y)
{
libclut_model_ciexyz_to_cie_1960_ucs(x, y, z, u, v, Y);
}
/**
* Convert from CIEUVW to CIE 1960 UCS.
*
* @param U The U* component.
* @param V The V* component.
* @param W The W* component.
* @param u0 The u parameter for the white point.
* @param v0 The v parameter for the white point.
* @param u Output parameter for the u parameter.
* @param v Output parameter for the v parameter.
* @param Y Output parameter for the Y parameter.
*/
void (libclut_model_cieuvw_to_cie_1960_ucs)(double U, double V, double W, double u0, double v0,
double* u, double* v, double* Y)
{
libclut_model_cieuvw_to_cie_1960_ucs(U, V, W, u0, v0, u, v, Y);
}
/**
* Convert from CIE 1960 UCS to CIEUVW.
*
* Requires linking with `-lm`.
*
* @param u The u component.
* @param v The v component.
* @param Y The Y component.
* @param u0 The u parameter for the white point.
* @param v0 The v parameter for the white point.
* @param U Output parameter for the U* parameter.
* @param V Output parameter for the V* parameter.
* @param W Output parameter for the W* parameter.
*/
void (libclut_model_cie_1960_ucs_to_cieuvw)(double u, double v, double Y, double u0, double v0,
double* U, double* V, double* W)
{
libclut_model_cie_1960_ucs_to_cieuvw(u, v, Y, u0, v0, U, V, W);
}
/**
* Divide all values in a row by a divisor.
*
* @param m The first part of the row.
* @param a The second part of the row.
* @param d The divisor.
*/
static void divrow(double m[3], double a[3], double d)
{
m[0] /= d, m[1] /= d, m[2] /= d;
a[0] /= d, a[1] /= d, a[2] /= d;
}
/**
* Subtract all values in a row by corresponding value
* in another row multiplied by a common value.
*
* @param a1 The first part of the minuend/difference row.
* @param a2 The second part of the minuend/difference row.
* @param b1 The first part of the subtrahend row.
* @param b2 The second part of the subtrahend row.
* @param m The multiplier.
*/
static void subrow(double a1[3], double a2[3], double b1[3], double b2[3], double m)
{
a1[0] -= b1[0] * m, a1[1] -= b1[1] * m, a1[2] -= b1[2] * m;
a2[0] -= b2[0] * m, a2[1] -= b2[1] * m, a2[2] -= b2[2] * m;
}
/**
* Invert a matrix.
*
* @param M The matrix to invert, will be modified to an
* identity matrix, possibly with reordered rows.
* @param A The inversion of M (as input).
* @return 1 on success, 0 if the matrix is not invertible.
*/
static int invert(libclut_colour_space_conversion_matrix_t M, libclut_colour_space_conversion_matrix_t A)
{
int r0 = 0, r1 = 1, r2 = 2, t, swapped = 0;
libclut_colour_space_conversion_matrix_t T;
A[0][0] = A[1][1] = A[2][2] = 1;
A[0][1] = A[0][2] = A[1][0] = A[1][2] = A[2][0] = A[2][1] = 0;
if (libclut_0__(M[r0][0]))
{
if (libclut_0__(M[r1][0]))
{
if (libclut_0__(M[r2][0]))
return 0;
t = r0, r0 = r2, r2 = t;
}
else
t = r0, r0 = r1, r1 = t;
swapped = 1;
}
divrow(M[r0], A[r0], M[r0][0]);
subrow(M[r1], A[r1], M[r0], A[r0], M[r1][0]);
subrow(M[r2], A[r2], M[r0], A[r0], M[r2][0]);
if (libclut_0__(M[r1][1]))
{
if (libclut_0__(M[r2][1]))
return 0;
t = r1, r1 = r2, r2 = t;
swapped = 1;
}
divrow(M[r1], A[r1], M[r1][1]);
subrow(M[r2], A[r2], M[r1], A[r1], M[r2][1]);
if (libclut_0__(M[r2][2]))
return 0;
divrow(M[r2], A[r2], M[r2][2]);
subrow(M[r1], A[r1], M[r2], A[r2], M[r1][2]);
subrow(M[r0], A[r0], M[r2], A[r2], M[r0][2]);
subrow(M[r0], A[r0], M[r1], A[r1], M[r0][1]);
if (swapped)
{
memcpy(T, A, sizeof(T));
memcpy(A[0], T[r0], sizeof(*T));
memcpy(A[1], T[r1], sizeof(*T));
memcpy(A[2], T[r2], sizeof(*T));
}
return 1;
}
/**
* Create an RGB to CIE XYZ conversion matrix.
*
* @param cs The colour space.
* @param M The output matrix.
* @return Zero on success, -1 on error.
*
* @throws EINVAL The colour space cannot be used.
*/
static int get_conversion_matrix(const libclut_rgb_colour_space_t* cs, libclut_colour_space_conversion_matrix_t M)
{
#define XYY_TO_XYZ(x, y, Y, Xp, Yp, Zp) \
(libclut_0__(Y)) ? \
(*(Xp) = *(Zp) = 0, *(Yp) = (Y)) : \
(*(Xp) = (x) * (Y) / (y), \
*(Yp) = (Y), \
*(Zp) = (1 - (x) - (y)) * (Y) / (y))
double Xr, Yr, Zr, Xg, Yg, Zg, Xb, Yb, Zb, Xw, Yw, Zw, Sr, Sg, Sb;
libclut_colour_space_conversion_matrix_t M2;
XYY_TO_XYZ(cs->red_x, cs->red_y, 1, &Xr, &Yr, &Zr);
XYY_TO_XYZ(cs->green_x, cs->green_y, 1, &Xg, &Yg, &Zg);
XYY_TO_XYZ(cs->blue_x, cs->blue_y, 1, &Xb, &Yb, &Zb);
XYY_TO_XYZ(cs->white_x, cs->white_y, cs->white_Y, &Xw, &Yw, &Zw);
M2[0][0] = Xr, M2[0][1] = Xg, M2[0][2] = Xb;
M2[1][0] = Yr, M2[1][1] = Yg, M2[1][2] = Yb;
M2[2][0] = Zr, M2[2][1] = Zg, M2[2][2] = Zb;
if (!invert(M2, M))
return errno = EINVAL, -1;
Sr = M[0][0] * Xw + M[0][1] * Yw + M[0][2] * Zw;
Sg = M[1][0] * Xw + M[1][1] * Yw + M[1][2] * Zw;
Sb = M[2][0] * Xw + M[2][1] * Yw + M[2][2] * Zw;
M[0][0] = Sr * Xr, M[0][1] = Sg * Xg, M[0][2] = Sb * Xb;
M[1][0] = Sr * Yr, M[1][1] = Sg * Yg, M[1][2] = Sb * Yb;
M[2][0] = Sr * Zr, M[2][1] = Sg * Zg, M[2][2] = Sb * Zb;
return 0;
#undef XYY_TO_XYZ
}
/**
* Create a matrix for converting values between
* two RGB colour spaces.
*
* @param from The input colour space, the Y-component is only necessary
* for the white point, `NULL` for CIE XYZ.
* @param to The output colour space, the Y-component is only necessary
* for the white point, `NULL` for CIE XYZ.
* @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 colour space cannot be used.
*/
int libclut_model_get_rgb_conversion_matrix(const libclut_rgb_colour_space_t* from,
const libclut_rgb_colour_space_t* to,
libclut_colour_space_conversion_matrix_t M,
libclut_colour_space_conversion_matrix_t Minv)
{
libclut_colour_space_conversion_matrix_t A, B;
if (from != NULL)
{
if (get_conversion_matrix(from, A))
return -1;
}
else
{
A[0][0] = A[1][1] = A[2][2] = 1;
A[0][1] = A[1][0] = A[2][0] = 0;
A[0][2] = A[1][2] = A[2][1] = 0;
}
if (to != NULL)
{
if (get_conversion_matrix(to, M))
return -1;
if (!invert(M, B))
return errno = EINVAL, -1;
if (from != NULL)
{
M[0][0] = B[0][0] * A[0][0] + B[0][1] * A[1][0] + B[0][2] * A[2][0];
M[0][1] = B[0][0] * A[0][1] + B[0][1] * A[1][1] + B[0][2] * A[2][1];
M[0][2] = B[0][0] * A[0][2] + B[0][1] * A[1][2] + B[0][2] * A[2][2];
M[1][0] = B[1][0] * A[0][0] + B[1][1] * A[1][0] + B[1][2] * A[2][0];
M[1][1] = B[1][0] * A[0][1] + B[1][1] * A[1][1] + B[1][2] * A[2][1];
M[1][2] = B[1][0] * A[0][2] + B[1][1] * A[1][2] + B[1][2] * A[2][2];
M[2][0] = B[2][0] * A[0][0] + B[2][1] * A[1][0] + B[2][2] * A[2][0];
M[2][1] = B[2][0] * A[0][1] + B[2][1] * A[1][1] + B[2][2] * A[2][1];
M[2][2] = B[2][0] * A[0][2] + B[2][1] * A[1][2] + B[2][2] * A[2][2];
}
else
memcpy(M, B, sizeof(B));
}
else
memcpy(M, A, sizeof(A));
if (Minv != NULL)
{
memcpy(A, M, sizeof(A));
if (!invert(A, Minv))
return errno = EINVAL, -1;
}
return 0;
}
/**
* Convert an RGB colour into another RGB colour space.
*
* Both RGB colour spaces must have same gamma functions as sRGB.
*
* @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`.
* @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.
*/
void (libclut_model_convert_rgb)(double r, double g, double b, libclut_colour_space_conversion_matrix_t M,
double* out_r, double* out_g, double* out_b)
{
libclut_model_convert_rgb(r, g, b, M, out_r, out_g, out_b);
}
/**
* Convert an RGB colour of a custom RGB colour space to CIE XYZ.
*
* The RGB colour space must have same gamma functions as sRGB.
*
* @param r The red component.
* @param g The green component.
* @param b The blue component.
* @param M Conversion matrix, create with `libclut_model_get_rgb_conversion_matrix`.
* @param x Output parameter for the X component.
* @param y Output parameter for the Y component.
* @param z Output parameter for the Z component.
*/
void (libclut_model_rgb_to_ciexyz)(double r, double g, double b, libclut_colour_space_conversion_matrix_t M,
double* x, double* y, double* z)
{
libclut_model_rgb_to_ciexyz(r, g, b, M, x, y, z);
}
/**
* Convert a CIE XYZ colour to a custom RGB colour space.
*
* The RGB colour space must have same gamma functions as sRGB.
*
* @param x The X component.
* @param y The Y component.
* @param z The Z component.
* @param M Conversion matrix, create with `libclut_model_get_rgb_conversion_matrix`.
* @param r Output parameter for the red component.
* @param g Output parameter for the green component
* @param b Output parameter for the blue component.
*/
void (libclut_model_ciexyz_to_rgb)(double x, double y, double z, libclut_colour_space_conversion_matrix_t M,
double* r, double* g, double* b)
{
libclut_model_ciexyz_to_rgb(x, y, z, M, r, g, b);
}
