Add support for more advanced color correction

ash/display/display_color_manager_chromeos.cc

Index: ash/display/display_color_manager_chromeos.cc
diff --git a/ash/display/display_color_manager_chromeos.cc b/ash/display/display_color_manager_chromeos.cc
index 1241978958018acff967d30fbfd9dcb2d0c961dd..3a6ec86939f9339dc49687e4010bbaa547cab9e2 100644
--- a/ash/display/display_color_manager_chromeos.cc
+++ b/ash/display/display_color_manager_chromeos.cc
@@ -31,10 +31,26 @@ namespace ash {
 
 namespace {
 
-bool ParseFile(const base::FilePath& path,
+base::FilePath PathForProductID(int64_t product_id) {

[dcheng, 2016/02/23 20:01:55]

#include <stdint.h>

[robert.bradford, 2016/02/24 12:34:20]

Done.

+  base::FilePath path;
+  CHECK(
+      PathService::Get(chromeos::DIR_DEVICE_COLOR_CALIBRATION_PROFILES, &path));
+  path = path.Append(base::StringPrintf("%08" PRIx64 ".icc", product_id));
+  return path;
+}
+
+bool ParseFile(bool has_color_correction_matrix,
+               int64_t product_id,
                DisplayColorManager::ColorCalibrationData* data) {
+  base::FilePath path = PathForProductID(product_id);
+  VLOG(1) << "Trying ICC file " << path.value()
+          << " with product id: " << product_id
+          << " has_color_correction_matrix: "
+          << (has_color_correction_matrix ? "true" : "false");
+
   if (!base::PathExists(path))  // No icc file for this display; not an error.
     return false;
+
   qcms_profile* display_profile = qcms_profile_from_path(path.value().c_str());
 
   if (!display_profile) {
@@ -44,39 +60,113 @@ bool ParseFile(const base::FilePath& path,
 
   size_t vcgt_channel_length =
       qcms_profile_get_vcgt_channel_length(display_profile);
-  if (!vcgt_channel_length) {
+
+  if (!has_color_correction_matrix && !vcgt_channel_length) {
     LOG(WARNING) << "No vcgt table in ICC file: " << path.value();
     qcms_profile_release(display_profile);
     return false;
   }
 
-  std::vector<uint16_t> vcgt_data;
-  vcgt_data.resize(vcgt_channel_length * 3);
-  if (!qcms_profile_get_vcgt_rgb_channels(display_profile, &vcgt_data[0])) {
-    LOG(WARNING) << "Unable to get vcgt data";
-    qcms_profile_release(display_profile);
-    return false;
-  }
+  if (vcgt_channel_length) {
+    if (has_color_correction_matrix) {
+      VLOG(1) << "Using VCGT data on CTM enabled platform.";
+    }
+
+    std::vector<uint16_t> vcgt_data;
+    vcgt_data.resize(vcgt_channel_length * 3);
+    if (!qcms_profile_get_vcgt_rgb_channels(display_profile, &vcgt_data[0])) {
+      LOG(WARNING) << "Unable to get vcgt data";
+      qcms_profile_release(display_profile);
+      return false;
+    }
+
+    data->gamma_lut.resize(vcgt_channel_length);
+    for (size_t i = 0; i < vcgt_channel_length; ++i) {
+      data->gamma_lut[i].r = vcgt_data[i];
+      data->gamma_lut[i].g = vcgt_data[vcgt_channel_length + i];
+      data->gamma_lut[i].b = vcgt_data[(vcgt_channel_length * 2) + i];
+    }
+  } else {
+    VLOG(1) << "Using full degamma/gamma/CTM from profile.";
+    qcms_profile* srgb_profile = qcms_profile_sRGB();
+
+    qcms_transform* transform =
+        qcms_transform_create(srgb_profile, QCMS_DATA_RGB_8, display_profile,
+                              QCMS_DATA_RGB_8, QCMS_INTENT_PERCEPTUAL);
+
+    if (!transform) {
+      LOG(WARNING)
+          << "Unable to create transformation from sRGB to display profile.";
+
+      qcms_profile_release(display_profile);
+      qcms_profile_release(srgb_profile);
+      return false;
+    }
+
+    if (!qcms_transform_is_matrix(transform)) {
+      LOG(WARNING) << "No transformation matrix available";
 
-  data->lut.resize(vcgt_channel_length);
-  for (size_t i = 0; i < vcgt_channel_length; ++i) {
-    data->lut[i].r = vcgt_data[i];
-    data->lut[i].g = vcgt_data[vcgt_channel_length + i];
-    data->lut[i].b = vcgt_data[(vcgt_channel_length * 2) + i];
+      qcms_transform_release(transform);
+      qcms_profile_release(display_profile);
+      qcms_profile_release(srgb_profile);
+      return false;
+    }
+
+    size_t degamma_size = qcms_transform_get_input_trc_rgba(
+        transform, srgb_profile, QCMS_TRC_USHORT, NULL);
+    size_t gamma_size = qcms_transform_get_output_trc_rgba(
+        transform, display_profile, QCMS_TRC_USHORT, NULL);
+
+    if (degamma_size == 0 || gamma_size == 0) {
+      LOG(WARNING)
+          << "Invalid number of elements in gamma tables: degamma size = "
+          << degamma_size << " gamma size = " << gamma_size;
+
+      qcms_transform_release(transform);
+      qcms_profile_release(display_profile);
+      qcms_profile_release(srgb_profile);
+      return false;
+    }
+
+    std::vector<uint16_t> degamma_data;
+    std::vector<uint16_t> gamma_data;
+    degamma_data.resize(degamma_size * 4);
+    gamma_data.resize(gamma_size * 4);
+
+    qcms_transform_get_input_trc_rgba(transform, srgb_profile, QCMS_TRC_USHORT,
+                                      &degamma_data[0]);
+    qcms_transform_get_output_trc_rgba(transform, display_profile,
+                                       QCMS_TRC_USHORT, &gamma_data[0]);
+
+    data->degamma_lut.resize(degamma_size);
+    for (size_t i = 0; i < degamma_size; ++i) {
+      data->degamma_lut[i].r = degamma_data[i * 4];
+      data->degamma_lut[i].g = degamma_data[(i * 4) + 1];
+      data->degamma_lut[i].b = degamma_data[(i * 4) + 2];
+    }
+
+    data->gamma_lut.resize(gamma_size);
+    for (size_t i = 0; i < gamma_size; ++i) {
+      data->gamma_lut[i].r = gamma_data[i * 4];
+      data->gamma_lut[i].g = gamma_data[(i * 4) + 1];
+      data->gamma_lut[i].b = gamma_data[(i * 4) + 2];
+    }
+
+    data->correction_matrix.resize(9);
+    for (int i = 0; i < 9; ++i) {
+      data->correction_matrix[i] =
+          qcms_transform_get_matrix(transform, i / 3, i % 3);
+    }
+
+    qcms_transform_release(transform);
+    qcms_profile_release(srgb_profile);
   }
+
+  VLOG(1) << "ICC file successfully parsed";
   qcms_profile_release(display_profile);
   return true;
 }
 
-base::FilePath PathForDisplaySnapshot(const ui::DisplaySnapshot* snapshot) {
-  base::FilePath path;
-  CHECK(
-      PathService::Get(chromeos::DIR_DEVICE_COLOR_CALIBRATION_PROFILES, &path));
-  path = path.Append(
-      base::StringPrintf("%08" PRIx64 ".icc", snapshot->product_id()));
-  return path;
-}
-
 }  // namespace
 
 DisplayColorManager::DisplayColorManager(
@@ -106,9 +196,11 @@ void DisplayColorManager::OnDisplayModeChanged(
 void DisplayColorManager::ApplyDisplayColorCalibration(int64_t display_id,
                                                        int64_t product_id) {
   if (calibration_map_.find(product_id) != calibration_map_.end()) {
-    ColorCalibrationData* ramp = calibration_map_[product_id];
-    if (!configurator_->SetGammaRamp(display_id, ramp->lut))
-      LOG(WARNING) << "Error applying gamma ramp";
+    ColorCalibrationData* data = calibration_map_[product_id];
+    if (!configurator_->SetColorCorrection(display_id, data->degamma_lut,
+                                           data->gamma_lut,
+                                           data->correction_matrix))
+      LOG(WARNING) << "Error applying color correction data";
   }
 }
 
@@ -119,14 +211,12 @@ void DisplayColorManager::LoadCalibrationForDisplay(
     return;
   }
 
-  base::FilePath path = PathForDisplaySnapshot(display);
-  VLOG(1) << "Loading ICC file " << path.value()
-          << " for display id: " << display->display_id()
-          << " with product id: " << display->product_id();
-
   scoped_ptr<ColorCalibrationData> data(new ColorCalibrationData());
-  base::Callback<bool(void)> request(
-      base::Bind(&ParseFile, path, base::Unretained(data.get())));
+  base::Callback<bool(void)> request;
+  request = base::Callback<bool(void)>(

[dcheng, 2016/02/23 20:01:54]

What's this cast for?

[robert.bradford, 2016/02/24 12:34:20]

Spurious. Fixed!

+      base::Bind(&ParseFile, display->has_color_correction_matrix(),
+                 display->product_id(), base::Unretained(data.get())));
+
   base::PostTaskAndReplyWithResult(
       blocking_pool_, FROM_HERE, request,
       base::Bind(&DisplayColorManager::UpdateCalibrationData, AsWeakPtr(),