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-rw-r--r--TODO3
-rw-r--r--src/libcolour.c89
-rw-r--r--src/test.c151
3 files changed, 215 insertions, 28 deletions
diff --git a/TODO b/TODO
index f479100..ada1788 100644
--- a/TODO
+++ b/TODO
@@ -5,7 +5,8 @@ Colour spaces:
YCbCr
TSL
Y'UV
- Hunter 1948 color space
+ Hunter 1948 color space (see Wikipedia article on CIELAB)
+ CIELCh (CIEHLC) (see Wikipedia article on CIELAB)
Support for generic additive colour spaces (3 channels and more)
Support for generic subtractive colour spaces (3 channels and more)
diff --git a/src/libcolour.c b/src/libcolour.c
index d60c44f..dd170af 100644
--- a/src/libcolour.c
+++ b/src/libcolour.c
@@ -16,6 +16,7 @@
*/
#include "libcolour.h"
+#include <alloca.h>
#include <errno.h>
#include <math.h>
#include <stdlib.h>
@@ -330,10 +331,9 @@ static void ciexyy_to_ciexyz(const libcolour_ciexyy_t* restrict from, libcolour_
}
}
-static inline double cielab_finv(double x)
+static inline double cielab_finv(double t)
{
- double x3 = x * x * x;
- return (x3 > 0.00885642) ? x3 : (x - 0.1379310) / (7.78 + 703 / 99900);
+ 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)
@@ -341,10 +341,10 @@ static void cielab_to_ciexyz(const libcolour_cielab_t* restrict from, libcolour_
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 / 300;
+ to->Z = to->Y - b / 200;
to->X = cielab_finv(to->X) * 0.95047;
- to->Y = cielab_finv(to->Y);
- to->Z = cielab_finv(to->Z) * 1.08883;
+ 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)
@@ -446,9 +446,9 @@ static void to_ciexyz(const libcolour_colour_t* restrict from, libcolour_ciexyz_
}
-static inline double cielab_f(double x)
+static inline double cielab_f(double t)
{
- return (x > 0.00885642) ? cbrt(x) : x * (7.78 + 703 / 99900) + 0.1379310;
+ 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)
@@ -492,14 +492,14 @@ static void ciexyz_to_cieluv(const libcolour_ciexyz_t* restrict from, libcolour_
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 + 4 * from->Z;
+ 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;
+ y *= 13;
to->u = u * y;
to->v = v * y;
}
@@ -535,6 +535,9 @@ static void other_to_cieluv(const libcolour_colour_t* restrict from, libcolour_c
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_CIELCH:
cielch_to_cieluv(&from->cielch, to);
return;
@@ -563,7 +566,7 @@ static void cieluv_to_cielch(const libcolour_cieluv_t* restrict from, libcolour_
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->u;
+ L = from->L, u = from->u, v = from->v;
}
to->L = L;
to->C = sqrt(u * u + v * v);
@@ -611,9 +614,14 @@ static void to_yiq(const libcolour_colour_t* restrict from, libcolour_yiq_t* res
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;
@@ -641,9 +649,14 @@ static void to_ydbdr(const libcolour_colour_t* restrict from, libcolour_ydbdr_t*
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;
@@ -686,9 +699,14 @@ static void to_ypbpr(const libcolour_colour_t* restrict from, libcolour_ypbpr_t*
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;
@@ -707,9 +725,14 @@ static void to_ycgco(const libcolour_colour_t* restrict from, libcolour_ycgco_t*
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;
@@ -766,7 +789,7 @@ static void to_cieuvw(const libcolour_colour_t* restrict from, libcolour_cieuvw_
to_cie1960ucs(from, &tmp.cie1960ucs);
/* fall through */
case LIBCOLOUR_CIE1960UCS:
- U = from->cie1960ucs.u, V = from->cie1960ucs.v, W = from->cie1960ucs.Y;
+ 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);
@@ -780,7 +803,9 @@ static void to_cieuvw(const libcolour_colour_t* restrict from, libcolour_cieuvw_
int libcolour_convert(const libcolour_colour_t* restrict from, libcolour_colour_t* restrict to)
{
- if (from->model < 0 || from->model > LIBCOLOUR_CIEUVW) {
+#define X(C, T) 1 +
+ if (from->model < 0 || from->model > LIBCOLOUR_LIST_MODELS 0) {
+#undef X
errno = EINVAL;
return -1;
}
@@ -862,8 +887,10 @@ int libcolour_delta_e(const libcolour_colour_t* a, const libcolour_colour_t* b,
}
-static int eliminate(double** M, size_t n, size_t m)
+#define eliminate(M, n, m) eliminate_(n, m, &(M))
+static int eliminate_(size_t n, size_t m, double (*Mp)[n][m])
{
+#define M (*Mp)
size_t r1, r2, c;
double d;
double* R1;
@@ -894,7 +921,7 @@ static int eliminate(double** M, size_t n, size_t m)
}
for (r1 = n; --r1;) {
R1 = M[r1];
- for (r2 = r1; --r2;) {
+ for (r2 = r1; r2--;) {
R2 = M[r2];
d = R2[r1];
for (c = 0; c < m; c++)
@@ -902,6 +929,7 @@ static int eliminate(double** M, size_t n, size_t m)
}
}
return 0;
+#undef M
}
@@ -932,7 +960,7 @@ int libcolour_proper(libcolour_colour_t* colour)
m[0][0] = r.ciexyz.X, m[0][1] = g.ciexyz.X, m[0][2] = b.ciexyz.X, m[0][3] = w.ciexyz.X;
m[1][0] = r.ciexyz.Y, m[1][1] = g.ciexyz.Y, m[1][2] = b.ciexyz.Y, m[1][3] = w.ciexyz.Y;
m[2][0] = r.ciexyz.Z, m[2][1] = g.ciexyz.Z, m[2][2] = b.ciexyz.Z, m[2][3] = w.ciexyz.Z;
- if (eliminate((double**)m, 3, 4))
+ if (eliminate(m, 3, 4))
return -1;
colour->rgb.red.Y = m[0][3];
colour->rgb.green.Y = m[1][3];
@@ -968,14 +996,14 @@ static int get_primaries(libcolour_rgb_t* cs)
M[1][0] = r.ciexyz.Y, M[1][1] = g.ciexyz.Y, M[1][2] = b.ciexyz.Y, M[1][3] = 0, M[1][4] = 1, M[1][5] = 0;
M[2][0] = r.ciexyz.Z, M[2][1] = g.ciexyz.Z, M[2][2] = b.ciexyz.Z, M[2][3] = 0, M[2][4] = 0, M[2][5] = 1;
- if (eliminate((double**)M, 3, 6))
+ if (eliminate(M, 3, 6))
return -1;
memcpy(M[0], M[0] + 3, 3 * sizeof(double)), M[0][3] = Sr;
memcpy(M[1], M[1] + 3, 3 * sizeof(double)), M[1][3] = Sg;
memcpy(M[2], M[2] + 3, 3 * sizeof(double)), M[2][3] = Sb;
- if (eliminate((double**)M, 3, 4))
+ if (eliminate(M, 3, 4))
return -1;
w.ciexyz.X = M[0][3];
@@ -1014,7 +1042,7 @@ static int get_matrices(libcolour_rgb_t* cs)
M[1][0] = r.ciexyz.Y, M[1][1] = g.ciexyz.Y, M[1][2] = b.ciexyz.Y, M[1][3] = 0, M[1][4] = 1, M[1][5] = 0;
M[2][0] = r.ciexyz.Z, M[2][1] = g.ciexyz.Z, M[2][2] = b.ciexyz.Z, M[2][3] = 0, M[2][4] = 0, M[2][5] = 1;
- if (eliminate((double**)M, 3, 6))
+ if (eliminate(M, 3, 6))
return -1;
Sr = M[0][3] * w.ciexyz.X + M[0][4] * w.ciexyz.Y + M[0][5] * w.ciexyz.Z;
@@ -1033,7 +1061,7 @@ static int get_matrices(libcolour_rgb_t* cs)
memcpy(M[1], cs->M[1], 3 * sizeof(double)), M[1][3] = 0, M[1][4] = 1, M[1][5] = 0;
memcpy(M[2], cs->M[2], 3 * sizeof(double)), M[2][3] = 0, M[2][4] = 0, M[2][5] = 1;
- if (eliminate((double**)M, 3, 6))
+ if (eliminate(M, 3, 6))
return -1;
memcpy(cs->Minv[0], M[0] + 3, 3 * sizeof(double));
@@ -1044,20 +1072,27 @@ static int get_matrices(libcolour_rgb_t* cs)
}
-static int invert(double **Minv, double **M, size_t n)
+#define invert(Minv, M, n) invert_(n, &(Minv), &(M))
+static int invert_(size_t n, double (*Minvp)[n][n], double (*Mp)[n][n])
{
- double J[3][6];
+#define Minv (*Minvp)
+#define M (*Mp)
+#define J (*Jp)
+ double J[n][2 * n] = alloca(sizeof(double[n][2 * n]));
size_t i;
for (i = 0; i < n; i++) {
memcpy(J[i], M[i], n * sizeof(double));
memset(J[i] + n, 0, n * sizeof(double));
J[i][n + i] = 1;
}
- if (eliminate((double**)J, n, 2 * n))
+ if (eliminate(J, n, 2 * n))
return -1;
for (i = 0; i < n; i++)
- memcpy(M[i], J[i] + n, n * sizeof(double));
+ memcpy(Minv[i], J[i] + n, n * sizeof(double));
return 0;
+#undef J
+#undef M
+#undef Minv
}
@@ -1082,7 +1117,7 @@ static void get_transfer_function(libcolour_colour_t* cs)
}
-int libcolour_rgb_colour_space(libcolour_rgb_t* cs, libcolour_rgb_colour_space_t space)
+int libcolour_get_rgb_colour_space(libcolour_rgb_t* cs, libcolour_rgb_colour_space_t space)
{
#define XYY(XVALUE, YVALUE) (libcolour_ciexyy_t){ .model = LIBCOLOUR_CIEXYY, .x = XVALUE, .y = YVALUE, .Y = 1}
@@ -1093,12 +1128,12 @@ int libcolour_rgb_colour_space(libcolour_rgb_t* cs, libcolour_rgb_colour_space_t
return 0;
case LIBCOLOUR_RGB_COLOUR_SPACE_CUSTOM_FROM_MATRIX:
- if (invert((double**)(cs->Minv), (double**)(cs->M), 3) || get_primaries(cs))
+ if (invert(cs->Minv, cs->M, 3) || get_primaries(cs))
return -1;
return 0;
case LIBCOLOUR_RGB_COLOUR_SPACE_CUSTOM_FROM_INV_MATRIX:
- if (invert((double**)(cs->M), (double**)(cs->Minv), 3) || get_primaries(cs))
+ if (invert(cs->M, cs->Minv, 3) || get_primaries(cs))
return -1;
return 0;
diff --git a/src/test.c b/src/test.c
new file mode 100644
index 0000000..13f4e91
--- /dev/null
+++ b/src/test.c
@@ -0,0 +1,151 @@
+/**
+ * Copyright © 2016 Mattias Andrée <maandree@kth.se>
+ *
+ * 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 "libcolour.h"
+
+#include <stdio.h>
+
+
+int test_convert_(libcolour_colour_t* c1, libcolour_colour_t* c2, libcolour_colour_t* c3)
+{
+ double ch1, ch2, ch3;
+ if (libcolour_convert(c1, c2))
+ return -1;
+ if (libcolour_convert(c2, c3))
+ return -1;
+ ch1 = c1->srgb.R - c3->srgb.R;
+ ch2 = c1->srgb.G - c3->srgb.G;
+ ch3 = c1->srgb.B - c3->srgb.B;
+ ch1 *= ch1;
+ ch2 *= ch2;
+ ch3 *= ch3;
+ if (ch1 > 0.0000001 ||
+ ch2 > 0.0000001 ||
+ ch3 > 0.0000001)
+ return 0;
+ return 1;
+}
+
+
+int test_convert(libcolour_colour_t* c1, libcolour_model_t model)
+{
+ libcolour_colour_t c2, c3;
+ int r1, r2;
+ c3 = *c1;
+ c2.model = model;
+ switch (model) {
+ case LIBCOLOUR_RGB:
+ c2.rgb.with_gamma = 0;
+ if (libcolour_get_rgb_colour_space(&c2.rgb, LIBCOLOUR_RGB_COLOUR_SPACE_SRGB) < 0)
+ return -1;
+ return test_convert_(c1, &c2, &c3);
+ case LIBCOLOUR_SRGB:
+ c2.srgb.with_gamma = 0;
+ if (r1 = test_convert_(c1, &c2, &c3), r1 < 0)
+ return -1;
+ c2.srgb.with_gamma = 1;
+ if (r2 = test_convert_(c1, &c2, &c3), r2 < 0)
+ return -1;
+ return r1 & r2;
+ case LIBCOLOUR_CIELUV:
+ case LIBCOLOUR_CIELCH:
+ c2.cielch.white.model = LIBCOLOUR_CIEXYZ;
+ c2.cielch.white.X = 1.0294;
+ c2.cielch.white.Y = 1;
+ c2.cielch.white.Z = 0.9118;
+ return test_convert_(c1, &c2, &c3);
+ case LIBCOLOUR_CIEUVW:
+ c2.cieuvw.u0 = 0.37;
+ c2.cieuvw.v0 = 0.30;
+ return test_convert_(c1, &c2, &c3);
+ default:
+ return test_convert_(c1, &c2, &c3);
+ }
+}
+
+
+int test_convert_all(libcolour_model_t model, const char* model_name)
+{
+ libcolour_colour_t c1;
+ int r, rc = 1;
+
+ c1.model = model;
+ c1.srgb.R = 0.2, c1.srgb.G = 0.5, c1.srgb.B = 0.9;
+
+ switch (model) {
+ case LIBCOLOUR_RGB:
+ c1.rgb.with_gamma = 0;
+ if (libcolour_get_rgb_colour_space(&c1.rgb, LIBCOLOUR_RGB_COLOUR_SPACE_SRGB) < 0)
+ return -1;
+ break;
+ case LIBCOLOUR_SRGB:
+ c1.srgb.with_gamma = 0;
+ break;
+ case LIBCOLOUR_CIELUV:
+ case LIBCOLOUR_CIELCH:
+ c1.cielch.white.model = LIBCOLOUR_CIEXYZ;
+ c1.cielch.white.X = 1.0294;
+ c1.cielch.white.Y = 1;
+ c1.cielch.white.Z = 0.9118;
+ break;
+ case LIBCOLOUR_CIEUVW:
+ c1.cieuvw.u0 = 0.37;
+ c1.cieuvw.v0 = 0.30;
+ break;
+ default:
+ break;
+ }
+
+ c1.srgb.with_gamma = 0;
+#define X(ENUM, TYPE)\
+ r = test_convert(&c1, ENUM);\
+ if (r < 0)\
+ return -1;\
+ if (!r)\
+ printf("%s -> %s -> %s failed\n", model_name, #ENUM, model_name), rc = 0;
+ LIBCOLOUR_LIST_MODELS;
+#undef X
+
+ return rc;
+}
+
+
+/**
+ * Test libcolour
+ *
+ * @return 0: All tests passed
+ * 1: At least one test fail
+ * 2: An error occurred
+ */
+int main(int argc, char* argv[])
+{
+ int r, rc = 0;
+
+#define X(ENUM, TYPE)\
+ r = test_convert_all(ENUM, #ENUM);\
+ if (r < 0)\
+ goto fail;\
+ if (!r)\
+ rc = 1;
+ LIBCOLOUR_LIST_MODELS;
+#undef X
+
+ return rc;
+ fail:
+ perror(*argv);
+ return 2;
+ (void) argc;
+}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-09 23:31:11 +0000