[qcms] Update primaries used to build internal sRGB profile

third_party/qcms/src/tests/qcms_test_internal_srgb.c

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the Chromium LICENSE file.
 
 #include "qcms.h"
 #include "qcms_test_util.h"
 
+#include <math.h> // sqrt
 #include <stdio.h>
 #include <stdint.h>
 #include <stdlib.h>
 
-// Colorant matrix for the official sRGB IEC61966-2.1 color (D50) primaries.
+// D50 adapted color primaries of the internal sRGB color profile.
 static s15Fixed16Number sRGB_reference[3][3] = {
-                {0x06fa2 /*0.436066*/,  /*0.385147*/ 0x06299, /*0.143066*/ 0x024a0},
-                {0x038f5 /*0.222488*/,  /*0.716873*/ 0x0b785, /*0.060608*/ 0x00f84},
-                {0x00390 /*0.013916*/,  /*0.097076*/ 0x018da, /*0.714096*/ 0x0b6cf}};
+    { 0x06fa0, 0x06296, 0x024a0 }, // ( 0.436035, 0.385101, 0.143066 )
+    { 0x038f2, 0x0b789, 0x00f85 }, // ( 0.222443, 0.716934, 0.060623 )
+    { 0x0038f, 0x018da, 0x0b6c4 }, // ( 0.013901, 0.097076, 0.713928 )
+};
+
+// Reference media white point of the sRGB IEC61966-2.1 color profile.
+static struct XYZNumber D65 = {
+    0xf351, 0x10000, 0x116cc // ( 0.950455, 1.000000, 1.089050 )
+};
+
+static float compute_icc_D50_distance(const qcms_profile *profile)
+{
+    float rX = s15Fixed16Number_to_float(profile->redColorant.X);
+    float gX = s15Fixed16Number_to_float(profile->greenColorant.X);
+    float bX = s15Fixed16Number_to_float(profile->blueColorant.X);
+    float rY = s15Fixed16Number_to_float(profile->redColorant.Y);
+    float gY = s15Fixed16Number_to_float(profile->greenColorant.Y);
+    float bY = s15Fixed16Number_to_float(profile->blueColorant.Y);
+    float rZ = s15Fixed16Number_to_float(profile->redColorant.Z);
+    float gZ = s15Fixed16Number_to_float(profile->greenColorant.Z);
+    float bZ = s15Fixed16Number_to_float(profile->blueColorant.Z);
+
+    float X = rX + gX + bX;
+    float Y = rY + gY + bY;
+    float Z = rZ + gZ + bZ;
+
+    float x = X / (X + Y + Z);
+    float y = Y / (X + Y + Z);
+
+    printf("Profile White point test: xyY [ %.6f %.6f %.6f ]\n", x, y, Y);
+
+    float xerr = x - 0.345702915;
+    float yerr = y - 0.358538597;
+    float Yerr = Y - 1.000000000;
+
+    return sqrt((xerr * xerr) + (yerr * yerr) + (Yerr * Yerr));
+}
 
 static int qcms_test_internal_srgb(size_t width,
-                size_t height,
-                int iterations,
-                const char *in_path,
-                const char *out_path,
-                const int force_software)
+        size_t height,
+        int iterations,
+        const char *in_path,
+        const char *out_path,
+        const int force_software)
 {
-        qcms_profile *profile = qcms_profile_sRGB();
-        s15Fixed16Number sRGB_internal[3][3];
-        s15Fixed16Number diff = 0;
-        int i, j;
+    qcms_profile *profile = qcms_profile_sRGB();
+    s15Fixed16Number sRGB_internal[3][3];
+    s15Fixed16Number diff = 0;
+    float error;
+    int i, j;
 
-        printf("Test qcms internal sRGB colorant matrix against official sRGB IEC61966-2.1 color (D50) primaries\n");
+    if (qcms_profile_is_bogus(profile)) {
+        fprintf(stderr, "Failure: the internal sRGB profile failed the bogus profile check\n");
+        qcms_profile_release(profile);
+        return -1;
+    }
 
-        sRGB_internal[0][0] = profile->redColorant.X;
-        sRGB_internal[1][0] = profile->redColorant.Y;
-        sRGB_internal[2][0] = profile->redColorant.Z;
-        sRGB_internal[0][1] = profile->greenColorant.X;
-        sRGB_internal[1][1] = profile->greenColorant.Y;
-        sRGB_internal[2][1] = profile->greenColorant.Z;
-        sRGB_internal[0][2] = profile->blueColorant.X;
-        sRGB_internal[1][2] = profile->blueColorant.Y;
-        sRGB_internal[2][2] = profile->blueColorant.Z;
+    printf("Test qcms internal sRGB color primaries against sRGB IEC61966-2.1 color primaries\n");

[Noel Gordon, 2016/03/26 03:53:40]

Also since you check 3 different things now (primaries, media white point, and
pcs white point), then perhaps having three helper functions would be better? 
Maybe like so ...

   check_profile_primaries(profile);
   check_profile_media_white_point(profile);
   check_profile_pcs_white_point(profile);

which might make the test a lot easier to read.

[radu.velea, 2016/03/28 07:57:32]

Done.

 
-        for (i = 0; i < 3; i++) {
-                for (j = 0; j < 3; j++) {
-                        s15Fixed16Number tmp = sRGB_internal[i][j] - sRGB_reference[i][j];
-                        printf("\t%d", tmp);
-                        diff += abs(tmp);
-                }
-                printf("\n");
-        }
+    sRGB_internal[0][0] = profile->redColorant.X;
+    sRGB_internal[1][0] = profile->redColorant.Y;
+    sRGB_internal[2][0] = profile->redColorant.Z;
+    sRGB_internal[0][1] = profile->greenColorant.X;
+    sRGB_internal[1][1] = profile->greenColorant.Y;
+    sRGB_internal[2][1] = profile->greenColorant.Z;
+    sRGB_internal[0][2] = profile->blueColorant.X;
+    sRGB_internal[1][2] = profile->blueColorant.Y;
+    sRGB_internal[2][2] = profile->blueColorant.Z;
 
-        qcms_profile_release(profile);
+    for (i = 0; i < 3; i++) {
+        for (j = 0; j < 3; j++) {
+            s15Fixed16Number tmp = sRGB_internal[i][j] - sRGB_reference[i][j];
+            printf("\t%d", tmp);
+            diff += abs(tmp);
+        }
+        printf("\n");
+    }
 
-        printf("Total error = 0x%x [%.6f]\n", diff, diff / 65536.0);
+    printf("Total error = 0x%x [%.6f]\n\n", diff, diff / 65536.0);
 
-        return diff;
+    printf("Test media white point against expected sRGB IEC61966-2.1 D65 XYZ values\n");
+    printf("Internal values = [0x%X, 0x%X, 0x%X]\n",
+            profile->mediaWhitePoint.X, profile->mediaWhitePoint.Y, profile->mediaWhitePoint.Z);
+
+    printf("White point error = [%d, %d, %d]\n\n",
+            profile->mediaWhitePoint.X - D65.X, profile->mediaWhitePoint.Y - D65.Y, profile->mediaWhitePoint.Z - D65.Z);
+
+    printf("Test PCS white point error\n");
+
+    // Compute distance from ICC D50 xyY.
+    error = compute_icc_D50_distance(profile);
+
+    printf("White point error: %.6f\n", error);
+
+    qcms_profile_release(profile);
+
+    return diff;
 }
 
 struct qcms_test_case qcms_test_internal_srgb_info = {
-                "qcms_test_internal_srgb",
-                qcms_test_internal_srgb,
-                QCMS_TEST_DISABLED
+        "qcms_test_internal_srgb",
+        qcms_test_internal_srgb,
+        QCMS_TEST_DISABLED
 };