Add new media image layout tests for video color profiles

third_party/WebKit/LayoutTests/media/resources/munsell-video-chart.js

Index: third_party/WebKit/LayoutTests/media/resources/munsell-video-chart.js
diff --git a/third_party/WebKit/LayoutTests/fast/images/resources/color-checker-munsell-chart.js b/third_party/WebKit/LayoutTests/media/resources/munsell-video-chart.js
similarity index 72%
copy from third_party/WebKit/LayoutTests/fast/images/resources/color-checker-munsell-chart.js
copy to third_party/WebKit/LayoutTests/media/resources/munsell-video-chart.js
index 2f494b316a5d03ca9371c20f55af00922a007951..61c0dd2a4018c00a58e5f28780809c2a263c1861 100644
--- a/third_party/WebKit/LayoutTests/fast/images/resources/color-checker-munsell-chart.js
+++ b/third_party/WebKit/LayoutTests/media/resources/munsell-video-chart.js
@@ -1,10 +1,9 @@
-function log(message) {
-  document.getElementById('log').textContent += message + '\n';
-}
+window.ignoreCyan = false;
 
-function testImageColors(source) {
-  var image = document.querySelector('img');
+function testImageColors(source, cyanInTargetGamut) {
+  window.ignoreCyan = !cyanInTargetGamut;
 
+  var image = document.querySelector('img');
   image.onload = function() {
     runAfterLayoutAndPaint(window.testRunner ? changeColorProfile : profileChanged);
   };
@@ -34,9 +33,13 @@ function drawImageToCanvas() {
   chartColorTransform(canvas);
 }
 
+function log(message) {
+  document.getElementById('log').textContent += message + '\n';
+}
+
 function getCanvasColor(canvas, i) {
   var x = 40 + (i % 6) * (canvas.width / 6);
-  var y = 40 + Math.floor(i / 6) * (canvas.height / 4);
+  var y = 40 + Math.floor(i / 6) * (canvas.height / 4 - 40);
   try {
     var data = canvas.getContext('2d').getImageData(x, y, 1, 1).data;
     if (data[3] == 255)
@@ -83,6 +86,24 @@ function getMunsellColor(i) {
   return munsell_srgb_colors[i];
 }
 
+function getStudioColor(i) {
+  if (!window.studio_srgb_colors) {
+    // Studio video range white & black and proportions thereof, in sRGB space.
+    window.studio_srgb_colors = new Array(
+      { color: 'SG White',      rgb: [ 237, 237, 237 ] },
+      { color: 'SG White 1/2',  rgb: [ 130, 130, 130 ] },
+      { color: 'SG White 1/4',  rgb: [  74,  74,  74 ] },
+      { color: 'SG Black 4x',   rgb: [  79,  79,  79 ] },
+      { color: 'SG Black 2x',   rgb: [  48,  48,  48 ] },
+      { color: 'SG Black',      rgb: [  31,  31,  31 ] }
+    );
+  }
+
+  if (i < 0 && i >= studio_srgb_colors.length)
+    return { color: 'invalid-color', rgb: [ 0, 0, 0 ] };
+  return studio_srgb_colors[i];
+}
+
 function getColorError(cx, cy) {
   var dr = (cx[0] - cy[0]);
   var dg = (cx[1] - cy[1]);
@@ -103,7 +124,7 @@ function drawRule(size) {
 
 function chartColorTransform(canvas) {
   /*
-   * Add header over table of color names, acutal and expected values, and the
+   * Add header over table of color names, actual and expected values, and the
    * per color error (Euclidean distance).
    */
   log(pad('Color') + pad('Actual') + pad('Expected') + 'dE');
@@ -112,25 +133,31 @@ function chartColorTransform(canvas) {
   var totalSquaredError = 0.0;
 
   /*
-   * Report per color error dE, by comparing with the expected Munsell colors.
+   * Report per color error dE, by comparing with the expected Munsell & Studio colors.
    */
-  for (var i = 0; i < 24;) {
-    var expected = getMunsellColor(i);
+  for (var i = 0; i < 30;) {
+    var expected = (i < 24) ? getMunsellColor(i) : getStudioColor(i - 24);
     var actual = getCanvasColor(canvas, i);
     var dE = getColorError(actual.rgb, expected.rgb);
 
     log(pad(expected.color) + pad(actual.rgb.join(',')) + pad(expected.rgb.join(',')) + dE);
-    totalSquaredError += dE * dE;
 
-    if (++i % 6 == 0 && i < 24)
+    if (ignoreCyan && (i + 1) == 18)
+      ; // Do not include the Munsell Cyan (out-of-srgb-gamut) color error.
+    else
+      totalSquaredError += dE * dE;
+
+    if (++i % 6 == 0 && i <= 24)
       drawRule();
   }
 
   /*
-   * Report the total RMS color error neglecting out-of-srgb-gamut color Cyan.
+   * Report the total RMS color error: lower is better, and should be << 2, which is the
+   * JND (Just Noticable Difference) perception threshold.  Above a JND, the color error
+   * is noticable to the human eye.
    */
   drawRule();
-  log('\nResult: total RMS color error: ' + Math.sqrt(totalSquaredError / 24.0).toFixed(2));
+  log('\nResult: total RMS color error: ' + Math.sqrt(totalSquaredError / 30.0).toFixed(2));
 
   if (window.testRunner)
     window.testRunner.notifyDone();