diff --git a/LayoutTests/ChangeLog b/LayoutTests/ChangeLog
index 0867816..8f7978b 100644
--- a/LayoutTests/ChangeLog
+++ b/LayoutTests/ChangeLog
@@ -1,3 +1,16 @@
+2019-10-18  Jer Noble  <jer.noble@apple.com>
+
+        Add experimental HDR MediaCapabilities support.
+        https://bugs.webkit.org/show_bug.cgi?id=203113
+
+        Reviewed by Eric Carlson.
+
+        * media/mediacapabilities/mock-decodingInfo-alphaChannel-expected.txt:
+        * media/mediacapabilities/mock-decodingInfo-hdr-expected.txt: Added.
+        * media/mediacapabilities/mock-decodingInfo-hdr.html: Added.
+        * platform/mac/media/mediacapabilities/hevc-decodingInfo-hdr-expected.txt: Added.
+        * platform/mac/media/mediacapabilities/hevc-decodingInfo-hdr.html: Added.
+
 2019-10-18  Jiewen Tan  <jiewen_tan@apple.com>
 
         [WebAuthn] Implement AuthenticatorCancel
diff --git a/LayoutTests/media/mediacapabilities/mock-decodingInfo-alphaChannel-expected.txt b/LayoutTests/media/mediacapabilities/mock-decodingInfo-alphaChannel-expected.txt
index 6718401..5de3bf7 100644
--- a/LayoutTests/media/mediacapabilities/mock-decodingInfo-alphaChannel-expected.txt
+++ b/LayoutTests/media/mediacapabilities/mock-decodingInfo-alphaChannel-expected.txt
@@ -10,7 +10,7 @@
 EXPECTED (info.supportedConfiguration.video.alphaChannel == 'false') OK
 RUN(promise = navigator.mediaCapabilities.decodingInfo({ type: 'file', video: { contentType: 'video/mp4; codecs="mock-with-alpha"', height: 720, bitrate: 1000, width: 1280, framerate: 24.5, alphaChannel: true }});)
 Promise resolved OK
-EXPECTED (info.supported == 'true'), OBSERVED 'false' FAIL
+EXPECTED (info.supported == 'true') OK
 EXPECTED (info.supportedConfiguration.video.alphaChannel == 'true') OK
 RUN(promise = navigator.mediaCapabilities.decodingInfo({ type: 'file', video: { contentType: 'video/mp4; codecs="mock-without-alpha"', height: 720, bitrate: 1000, width: 1280, framerate: 24.5, alphaChannel: false }});)
 Promise resolved OK
diff --git a/LayoutTests/media/mediacapabilities/mock-decodingInfo-hdr-expected.txt b/LayoutTests/media/mediacapabilities/mock-decodingInfo-hdr-expected.txt
new file mode 100644
index 0000000..2fd1576
--- /dev/null
+++ b/LayoutTests/media/mediacapabilities/mock-decodingInfo-hdr-expected.txt
@@ -0,0 +1,17 @@
+RUN(internals.enableMockMediaCapabilities())
+RUN(internals.settings.setMediaCapabilitiesExtensionsEnabled(true))
+RUN(internals.settings.setHDRMediaCapabilitiesEnabled(true))
+RUN(promise = navigator.mediaCapabilities.decodingInfo({ type: 'file', video: { contentType: 'video/mp4; codecs="mock-with-hdr"', height: 720, bitrate: 1000, width: 1280, framerate: 24.5 }});)
+Promise resolved OK
+EXPECTED (info.supported == 'true') OK
+EXPECTED (info.supportedConfiguration.video.colorGamut == 'null') OK
+RUN(promise = navigator.mediaCapabilities.decodingInfo({ type: 'file', video: { contentType: 'video/mp4; codecs="mock-with-hdr"', height: 720, bitrate: 1000, width: 1280, framerate: 24.5, colorGamut: 'rec2020' }});)
+Promise resolved OK
+EXPECTED (info.supported == 'true') OK
+EXPECTED (info.supportedConfiguration.video.colorGamut == 'rec2020') OK
+RUN(promise = navigator.mediaCapabilities.decodingInfo({ type: 'file', video: { contentType: 'video/mp4; codecs="mock"', height: 720, bitrate: 1000, width: 1280, framerate: 24.5, colorGamut: 'rec2020' }});)
+Promise resolved OK
+EXPECTED (info.supported == 'false') OK
+EXPECTED (info.supportedConfiguration.video.colorGamut == 'rec2020') OK
+END OF TEST
+
diff --git a/LayoutTests/media/mediacapabilities/mock-decodingInfo-hdr.html b/LayoutTests/media/mediacapabilities/mock-decodingInfo-hdr.html
new file mode 100644
index 0000000..f5d626d
--- /dev/null
+++ b/LayoutTests/media/mediacapabilities/mock-decodingInfo-hdr.html
@@ -0,0 +1,40 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <script src=../video-test.js></script>
+    <script type="text/javascript">
+    var promise;
+    var info;
+
+    async function doTest()
+    {
+        if (!window.internals) {
+            failTest("Internals is required for this test.")
+            return;
+        }
+
+        run('internals.enableMockMediaCapabilities()');
+        run('internals.settings.setMediaCapabilitiesExtensionsEnabled(true)');
+        run('internals.settings.setHDRMediaCapabilitiesEnabled(true)');
+
+        run("promise = navigator.mediaCapabilities.decodingInfo({ type: 'file', video: { contentType: 'video/mp4; codecs=\"mock-with-hdr\"', height: 720, bitrate: 1000, width: 1280, framerate: 24.5 }});");
+        info = await shouldResolve(promise);
+        testExpected('info.supported', true);
+        testExpected('info.supportedConfiguration.video.colorGamut', null);
+
+        run("promise = navigator.mediaCapabilities.decodingInfo({ type: 'file', video: { contentType: 'video/mp4; codecs=\"mock-with-hdr\"', height: 720, bitrate: 1000, width: 1280, framerate: 24.5, colorGamut: 'rec2020' }});");
+        info = await shouldResolve(promise);
+        testExpected('info.supported', true);
+        testExpected('info.supportedConfiguration.video.colorGamut', 'rec2020');
+
+        run("promise = navigator.mediaCapabilities.decodingInfo({ type: 'file', video: { contentType: 'video/mp4; codecs=\"mock\"', height: 720, bitrate: 1000, width: 1280, framerate: 24.5, colorGamut: 'rec2020' }});");
+        info = await shouldResolve(promise);
+        testExpected('info.supported', false);
+        testExpected('info.supportedConfiguration.video.colorGamut', 'rec2020');
+
+        endTest();
+    }
+    </script>
+</head>
+<body onload="doTest()" />
+</html>
diff --git a/LayoutTests/platform/mac/media/mediacapabilities/hevc-decodingInfo-hdr-expected.txt b/LayoutTests/platform/mac/media/mediacapabilities/hevc-decodingInfo-hdr-expected.txt
new file mode 100644
index 0000000..16d80f0
--- /dev/null
+++ b/LayoutTests/platform/mac/media/mediacapabilities/hevc-decodingInfo-hdr-expected.txt
@@ -0,0 +1,16 @@
+RUN(internals.settings.setMediaCapabilitiesExtensionsEnabled(true))
+RUN(internals.settings.setHDRMediaCapabilitiesEnabled(true))
+RUN(promise = navigator.mediaCapabilities.decodingInfo({ type: 'media-source', video: { contentType: 'video/mp4; codecs="hvc1.2.4.H153.B0"', height: 720, bitrate: 800000, width: 1280, framerate: 24.5 }});)
+Promise resolved OK
+EXPECTED (info.supported == 'true') OK
+EXPECTED (info.supportedConfiguration.video.hdrMetadataType == 'null') OK
+RUN(promise = navigator.mediaCapabilities.decodingInfo({ type: 'media-source', video: { contentType: 'video/mp4; codecs="hvc1.2.4.H153.B0"', height: 720, bitrate: 1000, width: 1280, framerate: 24.5, hdrMetadataType: 'smpteSt2086', transferFunction: 'pq' }});)
+Promise resolved OK
+EXPECTED (info.supported == 'true') OK
+EXPECTED (info.supportedConfiguration.video.hdrMetadataType == 'smpteSt2086') OK
+RUN(promise = navigator.mediaCapabilities.decodingInfo({ type: 'media-source', video: { contentType: 'video/mp4; codecs="avc1.640028"', height: 720, bitrate: 1000, width: 1280, framerate: 24.5, hdrMetadataType: 'smpteSt2086', transferFunction: 'pq' }});)
+Promise resolved OK
+EXPECTED (info.supported == 'false') OK
+EXPECTED (info.supportedConfiguration.video.hdrMetadataType == 'smpteSt2086') OK
+END OF TEST
+
diff --git a/LayoutTests/platform/mac/media/mediacapabilities/hevc-decodingInfo-hdr.html b/LayoutTests/platform/mac/media/mediacapabilities/hevc-decodingInfo-hdr.html
new file mode 100644
index 0000000..fa10d08
--- /dev/null
+++ b/LayoutTests/platform/mac/media/mediacapabilities/hevc-decodingInfo-hdr.html
@@ -0,0 +1,39 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <script src=../../../../media/video-test.js></script>
+    <script type="text/javascript">
+    var promise;
+    var info;
+
+    async function doTest()
+    {
+        if (!window.internals) {
+            failTest("Internals is required for this test.")
+            return;
+        }
+
+        run('internals.settings.setMediaCapabilitiesExtensionsEnabled(true)');
+        run('internals.settings.setHDRMediaCapabilitiesEnabled(true)');
+
+        run("promise = navigator.mediaCapabilities.decodingInfo({ type: 'media-source', video: { contentType: 'video/mp4; codecs=\"hvc1.2.4.H153.B0\"', height: 720, bitrate: 800000, width: 1280, framerate: 24.5 }});");
+        info = await shouldResolve(promise);
+        testExpected('info.supported', true);
+        testExpected('info.supportedConfiguration.video.hdrMetadataType', null);
+
+        run("promise = navigator.mediaCapabilities.decodingInfo({ type: 'media-source', video: { contentType: 'video/mp4; codecs=\"hvc1.2.4.H153.B0\"', height: 720, bitrate: 1000, width: 1280, framerate: 24.5, hdrMetadataType: 'smpteSt2086', transferFunction: 'pq' }});");
+        info = await shouldResolve(promise);
+        testExpected('info.supported', true);
+        testExpected('info.supportedConfiguration.video.hdrMetadataType', 'smpteSt2086');
+
+        run("promise = navigator.mediaCapabilities.decodingInfo({ type: 'media-source', video: { contentType: 'video/mp4; codecs=\"avc1.640028\"', height: 720, bitrate: 1000, width: 1280, framerate: 24.5, hdrMetadataType: 'smpteSt2086', transferFunction: 'pq' }});");
+        info = await shouldResolve(promise);
+        testExpected('info.supported', false);
+        testExpected('info.supportedConfiguration.video.hdrMetadataType', 'smpteSt2086');
+
+        endTest();
+    }
+    </script>
+</head>
+<body onload="doTest()" />
+</html>
diff --git a/Source/WebCore/CMakeLists.txt b/Source/WebCore/CMakeLists.txt
index 96f27e8..ed78c8f 100644
--- a/Source/WebCore/CMakeLists.txt
+++ b/Source/WebCore/CMakeLists.txt
@@ -292,6 +292,8 @@
     Modules/indexeddb/WorkerGlobalScopeIndexedDatabase.idl
 
     Modules/mediacapabilities/AudioConfiguration.idl
+    Modules/mediacapabilities/ColorGamut.idl
+    Modules/mediacapabilities/HdrMetadataType.idl
     Modules/mediacapabilities/MediaCapabilities.idl
     Modules/mediacapabilities/MediaCapabilitiesDecodingInfo.idl
     Modules/mediacapabilities/MediaCapabilitiesEncodingInfo.idl
@@ -302,8 +304,7 @@
     Modules/mediacapabilities/MediaEncodingConfiguration.idl
     Modules/mediacapabilities/MediaEncodingType.idl
     Modules/mediacapabilities/NavigatorMediaCapabilities.idl
-    Modules/mediacapabilities/ScreenColorGamut.idl
-    Modules/mediacapabilities/ScreenLuminance.idl
+    Modules/mediacapabilities/TransferFunction.idl
     Modules/mediacapabilities/VideoConfiguration.idl
 
     Modules/mediacontrols/MediaControlsHost.idl
diff --git a/Source/WebCore/ChangeLog b/Source/WebCore/ChangeLog
index 03e4c79..b253056 100644
--- a/Source/WebCore/ChangeLog
+++ b/Source/WebCore/ChangeLog
@@ -1,3 +1,45 @@
+2019-10-18  Jer Noble  <jer.noble@apple.com>
+
+        Add experimental HDR MediaCapabilities support.
+        https://bugs.webkit.org/show_bug.cgi?id=203113
+
+        Reviewed by Eric Carlson.
+
+        Tests: media/mediacapabilities/mock-decodingInfo-hdr.html
+               platform/mac/media/mediacapabilities/hevc-decodingInfo-hdr.html
+
+        Add support for MediaCapabilities.decodeInfo() HDR support detection.
+
+        Add new enum IDL types to MediaCapabilities and remove old unused ones. Add
+        mock implementation for HDR detection. Add Cocoa platform implementation.
+
+        * CMakeLists.txt:
+        * DerivedSources-input.xcfilelist:
+        * DerivedSources-output.xcfilelist:
+        * DerivedSources.make:
+        * Modules/mediacapabilities/ColorGamut.idl: 
+        * Modules/mediacapabilities/HdrMetadataType.idl: 
+        * Modules/mediacapabilities/ScreenLuminance.h: 
+        * Modules/mediacapabilities/TransferFunction.idl: 
+        * Modules/mediacapabilities/VideoConfiguration.idl:
+        * Scripts/GenerateSettings.rb:
+        * Sources.txt:
+        * WebCore.xcodeproj/project.pbxproj:
+        * bindings/scripts/CodeGenerator.pm:
+        (WK_ucfirst):
+        * bindings/scripts/CodeGeneratorJS.pm:
+        (ToMethodName):
+        * page/Settings.yaml:
+        * platform/graphics/cocoa/MediaEngineConfigurationFactoryCocoa.cpp:
+        (WebCore::createMediaPlayerDecodingConfigurationCocoa):
+        * platform/mediacapabilities/ColorGamut.h: 
+        * platform/mediacapabilities/HdrMetadataType.h: 
+        * platform/mediacapabilities/TransferFunction.h: 
+        * platform/mediacapabilities/VideoConfiguration.h:
+        * platform/mock/MediaEngineConfigurationFactoryMock.cpp:
+        (WebCore::canDecodeMedia):
+        (WebCore::canEncodeMedia):
+
 2019-10-18  Jiewen Tan  <jiewen_tan@apple.com>
 
         [WebAuthn] Implement AuthenticatorCancel
diff --git a/Source/WebCore/DerivedSources-input.xcfilelist b/Source/WebCore/DerivedSources-input.xcfilelist
index a8b6228..03cd92f 100644
--- a/Source/WebCore/DerivedSources-input.xcfilelist
+++ b/Source/WebCore/DerivedSources-input.xcfilelist
@@ -129,6 +129,8 @@
 $(PROJECT_DIR)/Modules/indexeddb/IDBVersionChangeEvent.idl
 $(PROJECT_DIR)/Modules/indexeddb/WorkerGlobalScopeIndexedDatabase.idl
 $(PROJECT_DIR)/Modules/mediacapabilities/AudioConfiguration.idl
+$(PROJECT_DIR)/Modules/mediacapabilities/ColorGamut.idl
+$(PROJECT_DIR)/Modules/mediacapabilities/HdrMetadataType.idl
 $(PROJECT_DIR)/Modules/mediacapabilities/MediaCapabilities.idl
 $(PROJECT_DIR)/Modules/mediacapabilities/MediaCapabilitiesDecodingInfo.idl
 $(PROJECT_DIR)/Modules/mediacapabilities/MediaCapabilitiesEncodingInfo.idl
@@ -139,8 +141,7 @@
 $(PROJECT_DIR)/Modules/mediacapabilities/MediaEncodingConfiguration.idl
 $(PROJECT_DIR)/Modules/mediacapabilities/MediaEncodingType.idl
 $(PROJECT_DIR)/Modules/mediacapabilities/NavigatorMediaCapabilities.idl
-$(PROJECT_DIR)/Modules/mediacapabilities/ScreenColorGamut.idl
-$(PROJECT_DIR)/Modules/mediacapabilities/ScreenLuminance.idl
+$(PROJECT_DIR)/Modules/mediacapabilities/TransferFunction.idl
 $(PROJECT_DIR)/Modules/mediacapabilities/VideoConfiguration.idl
 $(PROJECT_DIR)/Modules/mediacontrols/MediaControlsHost.idl
 $(PROJECT_DIR)/Modules/mediarecorder/BlobEvent.idl
diff --git a/Source/WebCore/DerivedSources-output.xcfilelist b/Source/WebCore/DerivedSources-output.xcfilelist
index 847d83e..615457d 100644
--- a/Source/WebCore/DerivedSources-output.xcfilelist
+++ b/Source/WebCore/DerivedSources-output.xcfilelist
@@ -298,6 +298,8 @@
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSClipboardItem.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSCloseEvent.cpp
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSCloseEvent.h
+$(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSColorGamut.cpp
+$(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSColorGamut.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSCommandLineAPIHost.cpp
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSCommandLineAPIHost.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSComment.cpp
@@ -863,6 +865,8 @@
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSHTMLVideoElementPictureInPicture.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSHashChangeEvent.cpp
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSHashChangeEvent.h
+$(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSHdrMetadataType.cpp
+$(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSHdrMetadataType.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSHistory.cpp
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSHistory.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSHkdfParams.cpp
@@ -1711,10 +1715,6 @@
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSSVGZoomEvent.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSScreen.cpp
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSScreen.h
-$(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSScreenColorGamut.cpp
-$(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSScreenColorGamut.h
-$(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSScreenLuminance.cpp
-$(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSScreenLuminance.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSScriptProcessorNode.cpp
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSScriptProcessorNode.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSScrollIntoViewOptions.cpp
@@ -1829,6 +1829,8 @@
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSTouchList.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSTrackEvent.cpp
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSTrackEvent.h
+$(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSTransferFunction.cpp
+$(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSTransferFunction.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSTransitionEvent.cpp
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSTransitionEvent.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebCore/JSTreeWalker.cpp
diff --git a/Source/WebCore/DerivedSources.make b/Source/WebCore/DerivedSources.make
index 64de599..77b4443 100644
--- a/Source/WebCore/DerivedSources.make
+++ b/Source/WebCore/DerivedSources.make
@@ -203,6 +203,8 @@
     $(WebCore)/Modules/indexeddb/IDBVersionChangeEvent.idl \
     $(WebCore)/Modules/indexeddb/WorkerGlobalScopeIndexedDatabase.idl \
     $(WebCore)/Modules/mediacapabilities/AudioConfiguration.idl \
+    $(WebCore)/Modules/mediacapabilities/ColorGamut.idl \
+    $(WebCore)/Modules/mediacapabilities/HdrMetadataType.idl \
     $(WebCore)/Modules/mediacapabilities/MediaCapabilities.idl \
     $(WebCore)/Modules/mediacapabilities/MediaCapabilitiesDecodingInfo.idl \
     $(WebCore)/Modules/mediacapabilities/MediaCapabilitiesEncodingInfo.idl \
@@ -213,8 +215,7 @@
     $(WebCore)/Modules/mediacapabilities/MediaEncodingConfiguration.idl \
     $(WebCore)/Modules/mediacapabilities/MediaEncodingType.idl \
     $(WebCore)/Modules/mediacapabilities/NavigatorMediaCapabilities.idl \
-    $(WebCore)/Modules/mediacapabilities/ScreenColorGamut.idl \
-    $(WebCore)/Modules/mediacapabilities/ScreenLuminance.idl \
+    $(WebCore)/Modules/mediacapabilities/TransferFunction.idl \
     $(WebCore)/Modules/mediacapabilities/VideoConfiguration.idl \
     $(WebCore)/Modules/mediacontrols/MediaControlsHost.idl \
     $(WebCore)/Modules/mediarecorder/BlobEvent.idl \
diff --git a/Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.idl b/Source/WebCore/Modules/mediacapabilities/ColorGamut.idl
similarity index 98%
rename from Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.idl
rename to Source/WebCore/Modules/mediacapabilities/ColorGamut.idl
index 74b22cf..ed483f2 100644
--- a/Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.idl
+++ b/Source/WebCore/Modules/mediacapabilities/ColorGamut.idl
@@ -23,7 +23,7 @@
  * THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-enum ScreenColorGamut {
+enum ColorGamut {
     "srgb",
     "p3",
     "rec2020"
diff --git a/Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.idl b/Source/WebCore/Modules/mediacapabilities/HdrMetadataType.idl
similarity index 90%
copy from Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.idl
copy to Source/WebCore/Modules/mediacapabilities/HdrMetadataType.idl
index 74b22cf..6b1937f 100644
--- a/Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.idl
+++ b/Source/WebCore/Modules/mediacapabilities/HdrMetadataType.idl
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2017 Apple Inc. All rights reserved.
+ * Copyright (C) 2019 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -23,8 +23,8 @@
  * THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-enum ScreenColorGamut {
-    "srgb",
-    "p3",
-    "rec2020"
+enum HdrMetadataType {
+    "smpteSt2086",
+    "smpteSt2094-10",
+    "smpteSt2094-40"
 };
diff --git a/Source/WebCore/Modules/mediacapabilities/ScreenLuminance.h b/Source/WebCore/Modules/mediacapabilities/ScreenLuminance.h
deleted file mode 100644
index 8a235a3..0000000
--- a/Source/WebCore/Modules/mediacapabilities/ScreenLuminance.h
+++ /dev/null
@@ -1,49 +0,0 @@
-/*
- * Copyright (C) 2017 Apple Inc. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
- * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
- * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
- * THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#pragma once
-
-#include <wtf/RefCounted.h>
-
-namespace WebCore {
-
-class ScreenLuminance : public RefCounted<ScreenLuminance> {
-public:
-    double min() const { return m_min; }
-    void setMin(double min) { m_min = min; }
-
-    double max() const { return m_max; }
-    void setMax(double max) { m_max = max; }
-
-    double maxAverage() const { return m_maxAverage; }
-    void setMaxAverage(double maxAverage) { m_maxAverage = maxAverage; }
-
-private:
-    double m_min { 0 };
-    double m_max { 0 };
-    double m_maxAverage  { 0 };
-};
-
-}
diff --git a/Source/WebCore/Modules/mediacapabilities/ScreenLuminance.idl b/Source/WebCore/Modules/mediacapabilities/ScreenLuminance.idl
deleted file mode 100644
index 9e3dcab..0000000
--- a/Source/WebCore/Modules/mediacapabilities/ScreenLuminance.idl
+++ /dev/null
@@ -1,34 +0,0 @@
-/*
- * Copyright (C) 2017 Apple Inc. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
- * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
- * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
- * THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-[
-    EnabledBySetting=MediaCapabilities,
-    ImplementationLacksVTable
-]
-interface ScreenLuminance {
-  readonly attribute double min;
-  readonly attribute double max;
-  readonly attribute double maxAverage;
-};
diff --git a/Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.idl b/Source/WebCore/Modules/mediacapabilities/TransferFunction.idl
similarity index 92%
copy from Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.idl
copy to Source/WebCore/Modules/mediacapabilities/TransferFunction.idl
index 74b22cf..36e03f8 100644
--- a/Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.idl
+++ b/Source/WebCore/Modules/mediacapabilities/TransferFunction.idl
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2017 Apple Inc. All rights reserved.
+ * Copyright (C) 2019 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -23,8 +23,8 @@
  * THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-enum ScreenColorGamut {
+enum TransferFunction {
     "srgb",
-    "p3",
-    "rec2020"
+    "pq",
+    "hlg"
 };
diff --git a/Source/WebCore/Modules/mediacapabilities/VideoConfiguration.idl b/Source/WebCore/Modules/mediacapabilities/VideoConfiguration.idl
index bca1ef0..f72bfea4 100644
--- a/Source/WebCore/Modules/mediacapabilities/VideoConfiguration.idl
+++ b/Source/WebCore/Modules/mediacapabilities/VideoConfiguration.idl
@@ -34,4 +34,7 @@
   required unsigned long long bitrate;
   required double framerate;
   [EnabledBySetting=MediaCapabilitiesExtensions] boolean alphaChannel;
+  [EnabledBySetting=HDRMediaCapabilities] HdrMetadataType hdrMetadataType;
+  [EnabledBySetting=HDRMediaCapabilities] ColorGamut colorGamut;
+  [EnabledBySetting=HDRMediaCapabilities] TransferFunction transferFunction;
 };
diff --git a/Source/WebCore/Scripts/GenerateSettings.rb b/Source/WebCore/Scripts/GenerateSettings.rb
index 19a19bf..14bfa73 100755
--- a/Source/WebCore/Scripts/GenerateSettings.rb
+++ b/Source/WebCore/Scripts/GenerateSettings.rb
@@ -120,7 +120,7 @@
   end
 
   def setterFunctionName
-    if @name.start_with?("css", "xss", "ftp", "dom", "dns", "ice")
+    if @name.start_with?("css", "xss", "ftp", "dom", "dns", "ice", "hdr")
       "set" + @name[0..2].upcase + @name[3..@name.length]
     else
       "set" + @name[0].upcase + @name[1..@name.length]
diff --git a/Source/WebCore/Sources.txt b/Source/WebCore/Sources.txt
index 1726df5..e7c9046 100644
--- a/Source/WebCore/Sources.txt
+++ b/Source/WebCore/Sources.txt
@@ -2709,6 +2709,7 @@
 JSClipboardEvent.cpp
 JSClipboardItem.cpp
 JSCloseEvent.cpp
+JSColorGamut.cpp
 JSCommandLineAPIHost.cpp
 JSComment.cpp
 JSCompositionEvent.cpp
@@ -2969,6 +2970,7 @@
 JSHTMLVideoElement.cpp
 JSHTMLVideoElementPictureInPicture.cpp
 JSHashChangeEvent.cpp
+JSHdrMetadataType.cpp
 JSHistory.cpp
 JSHkdfParams.cpp
 JSHmacKeyParams.cpp
@@ -3353,7 +3355,6 @@
 JSSVGZoomAndPan.cpp
 JSSVGZoomEvent.cpp
 JSScreen.cpp
-JSScreenLuminance.cpp
 JSScriptProcessorNode.cpp
 JSScrollIntoViewOptions.cpp
 JSScrollLogicalPosition.cpp
@@ -3394,6 +3395,7 @@
 JSTextEvent.cpp
 JSTextMetrics.cpp
 JSTimeRanges.cpp
+JSTransferFunction.cpp
 JSTransitionEvent.cpp
 JSTreeWalker.cpp
 JSUndoItem.cpp
diff --git a/Source/WebCore/WebCore.xcodeproj/project.pbxproj b/Source/WebCore/WebCore.xcodeproj/project.pbxproj
index e24ef4d..0439398 100644
--- a/Source/WebCore/WebCore.xcodeproj/project.pbxproj
+++ b/Source/WebCore/WebCore.xcodeproj/project.pbxproj
@@ -13649,6 +13649,41 @@
 		CD4AC5281496AE2F0087C4EF /* Composite.wav */ = {isa = PBXFileReference; lastKnownFileType = audio.wav; name = Composite.wav; path = platform/audio/resources/Composite.wav; sourceTree = SOURCE_ROOT; };
 		CD4BE5291CE13425009D87DA /* GenericTaskQueue.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = GenericTaskQueue.cpp; sourceTree = "<group>"; };
 		CD4E0AFA11F7BC27009D3811 /* fullscreen.css */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.css; path = fullscreen.css; sourceTree = "<group>"; };
+		CD4E4E602357B317007895C3 /* HdrMetadataType.idl */ = {isa = PBXFileReference; lastKnownFileType = text; path = HdrMetadataType.idl; sourceTree = "<group>"; };
+		CD4E4E622357B3AD007895C3 /* TransferFunction.idl */ = {isa = PBXFileReference; lastKnownFileType = text; path = TransferFunction.idl; sourceTree = "<group>"; };
+		CD4E4E6C2357B556007895C3 /* JSMediaCapabilitiesEncodingInfo.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = JSMediaCapabilitiesEncodingInfo.h; sourceTree = "<group>"; };
+		CD4E4E6D2357B556007895C3 /* JSMediaCapabilitiesDecodingInfo.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = JSMediaCapabilitiesDecodingInfo.h; sourceTree = "<group>"; };
+		CD4E4E6E2357B556007895C3 /* JSMediaCapabilitiesInfo.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = JSMediaCapabilitiesInfo.h; sourceTree = "<group>"; };
+		CD4E4E6F2357B557007895C3 /* JSMediaCapabilities.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = JSMediaCapabilities.h; sourceTree = "<group>"; };
+		CD4E4E702357B557007895C3 /* JSMediaCapabilitiesInfo.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = JSMediaCapabilitiesInfo.cpp; sourceTree = "<group>"; };
+		CD4E4E712357B557007895C3 /* JSMediaCapabilitiesEncodingInfo.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = JSMediaCapabilitiesEncodingInfo.cpp; sourceTree = "<group>"; };
+		CD4E4E722357B558007895C3 /* JSMediaCapabilities.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = JSMediaCapabilities.cpp; sourceTree = "<group>"; };
+		CD4E4E7C2357B5FD007895C3 /* JSAudioConfiguration.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = JSAudioConfiguration.h; sourceTree = "<group>"; };
+		CD4E4E7D2357B5FD007895C3 /* JSMediaCapabilitiesInfo.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = JSMediaCapabilitiesInfo.h; sourceTree = "<group>"; };
+		CD4E4E7E2357B5FD007895C3 /* JSMediaConfiguration.dep */ = {isa = PBXFileReference; lastKnownFileType = file; path = JSMediaConfiguration.dep; sourceTree = "<group>"; };
+		CD4E4E7F2357B5FD007895C3 /* JSTransferFunction.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = JSTransferFunction.h; sourceTree = "<group>"; };
+		CD4E4E802357B5FE007895C3 /* JSMediaEncodingConfiguration.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = JSMediaEncodingConfiguration.cpp; sourceTree = "<group>"; };
+		CD4E4E812357B5FE007895C3 /* JSHdrMetadataType.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = JSHdrMetadataType.cpp; sourceTree = "<group>"; };
+		CD4E4E822357B5FE007895C3 /* JSMediaDecodingConfiguration.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = JSMediaDecodingConfiguration.h; sourceTree = "<group>"; };
+		CD4E4E832357B5FF007895C3 /* JSHdrMetadataType.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = JSHdrMetadataType.h; sourceTree = "<group>"; };
+		CD4E4E842357B5FF007895C3 /* JSColorGamut.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = JSColorGamut.cpp; sourceTree = "<group>"; };
+		CD4E4E852357B5FF007895C3 /* JSMediaCapabilitiesDecodingInfo.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = JSMediaCapabilitiesDecodingInfo.cpp; sourceTree = "<group>"; };
+		CD4E4E862357B600007895C3 /* JSColorGamut.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = JSColorGamut.h; sourceTree = "<group>"; };
+		CD4E4E872357B600007895C3 /* JSMediaConfiguration.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = JSMediaConfiguration.h; sourceTree = "<group>"; };
+		CD4E4E882357B600007895C3 /* JSMediaDecodingType.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = JSMediaDecodingType.h; sourceTree = "<group>"; };
+		CD4E4E892357B601007895C3 /* JSMediaDecodingConfiguration.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = JSMediaDecodingConfiguration.cpp; sourceTree = "<group>"; };
+		CD4E4E8C2357B602007895C3 /* JSTransferFunction.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = JSTransferFunction.cpp; sourceTree = "<group>"; };
+		CD4E4E8D2357B602007895C3 /* JSAudioConfiguration.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = JSAudioConfiguration.cpp; sourceTree = "<group>"; };
+		CD4E4E8E2357B602007895C3 /* JSMediaEncodingType.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = JSMediaEncodingType.h; sourceTree = "<group>"; };
+		CD4E4E8F2357B603007895C3 /* JSMediaEncodingType.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = JSMediaEncodingType.cpp; sourceTree = "<group>"; };
+		CD4E4E902357B603007895C3 /* JSMediaDecodingType.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = JSMediaDecodingType.cpp; sourceTree = "<group>"; };
+		CD4E4E912357B603007895C3 /* JSMediaEncodingConfiguration.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = JSMediaEncodingConfiguration.h; sourceTree = "<group>"; };
+		CD4E4E932357B604007895C3 /* JSMediaCapabilitiesInfo.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = JSMediaCapabilitiesInfo.cpp; sourceTree = "<group>"; };
+		CD4E4E972357BA8F007895C3 /* JSVideoConfiguration.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = JSVideoConfiguration.h; sourceTree = "<group>"; };
+		CD4E4E992357BA8F007895C3 /* JSVideoConfiguration.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = JSVideoConfiguration.cpp; sourceTree = "<group>"; };
+		CD4E4E9A2357CB9C007895C3 /* TransferFunction.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = TransferFunction.h; path = mediacapabilities/TransferFunction.h; sourceTree = "<group>"; };
+		CD4E4E9B2357CB9D007895C3 /* ColorGamut.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = ColorGamut.h; path = mediacapabilities/ColorGamut.h; sourceTree = "<group>"; };
+		CD4E4E9C2357CB9D007895C3 /* HdrMetadataType.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = HdrMetadataType.h; path = mediacapabilities/HdrMetadataType.h; sourceTree = "<group>"; };
 		CD5209E31B0BD8380077184E /* MediaPlayerEnums.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = MediaPlayerEnums.h; sourceTree = "<group>"; };
 		CD5209E51B0BD9E10077184E /* HTMLMediaElementEnums.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = HTMLMediaElementEnums.h; sourceTree = "<group>"; };
 		CD525BA21EE0B10700788DF5 /* FourCC.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = FourCC.h; sourceTree = "<group>"; };
@@ -13795,11 +13830,9 @@
 		CDBD3D291FE85CB90012C545 /* MediaConfiguration.idl */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = MediaConfiguration.idl; sourceTree = "<group>"; };
 		CDBD3D2A1FE85CBA0012C545 /* MediaEncodingConfiguration.idl */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = MediaEncodingConfiguration.idl; sourceTree = "<group>"; };
 		CDBD3D2B1FE85CBB0012C545 /* AudioConfiguration.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = AudioConfiguration.h; path = mediacapabilities/AudioConfiguration.h; sourceTree = "<group>"; };
-		CDBD3D2C1FE85CBB0012C545 /* ScreenLuminance.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ScreenLuminance.h; sourceTree = "<group>"; };
 		CDBD3D2D1FE85CBC0012C545 /* MediaEncodingType.idl */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = MediaEncodingType.idl; sourceTree = "<group>"; };
 		CDBD3D2E1FE85CBC0012C545 /* MediaDecodingType.idl */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = MediaDecodingType.idl; sourceTree = "<group>"; };
 		CDBD3D2F1FE85CBC0012C545 /* MediaCapabilities.idl */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = MediaCapabilities.idl; sourceTree = "<group>"; };
-		CDBD3D301FE85CBD0012C545 /* ScreenLuminance.idl */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = ScreenLuminance.idl; sourceTree = "<group>"; };
 		CDBD3D311FE85CBE0012C545 /* NavigatorMediaCapabilities.idl */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = NavigatorMediaCapabilities.idl; sourceTree = "<group>"; };
 		CDBD3D321FE85CBE0012C545 /* MediaCapabilities.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = MediaCapabilities.h; sourceTree = "<group>"; };
 		CDBD3D331FE85CBE0012C545 /* MediaCapabilitiesInfo.idl */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = MediaCapabilitiesInfo.idl; sourceTree = "<group>"; };
@@ -13809,11 +13842,10 @@
 		CDBD3D371FE85CC00012C545 /* MediaEncodingConfiguration.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = MediaEncodingConfiguration.h; path = mediacapabilities/MediaEncodingConfiguration.h; sourceTree = "<group>"; };
 		CDBD3D381FE85CC00012C545 /* MediaDecodingType.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = MediaDecodingType.h; path = mediacapabilities/MediaDecodingType.h; sourceTree = "<group>"; };
 		CDBD3D391FE85CC10012C545 /* NavigatorMediaCapabilities.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = NavigatorMediaCapabilities.h; sourceTree = "<group>"; };
-		CDBD3D3A1FE85CC10012C545 /* ScreenColorGamut.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ScreenColorGamut.h; sourceTree = "<group>"; };
 		CDBD3D3B1FE85CC20012C545 /* MediaDecodingConfiguration.idl */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = MediaDecodingConfiguration.idl; sourceTree = "<group>"; };
 		CDBD3D3C1FE85CC20012C545 /* AudioConfiguration.idl */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = AudioConfiguration.idl; sourceTree = "<group>"; };
 		CDBD3D3E1FE85CC30012C545 /* MediaEncodingType.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = MediaEncodingType.h; path = mediacapabilities/MediaEncodingType.h; sourceTree = "<group>"; };
-		CDBD3D3F1FE85CC30012C545 /* ScreenColorGamut.idl */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = ScreenColorGamut.idl; sourceTree = "<group>"; };
+		CDBD3D3F1FE85CC30012C545 /* ColorGamut.idl */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = ColorGamut.idl; sourceTree = "<group>"; };
 		CDBEAEAA19D92B6C00BEBA88 /* MediaSelectionGroupAVFObjC.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = MediaSelectionGroupAVFObjC.mm; sourceTree = "<group>"; };
 		CDBEAEAB19D92B6C00BEBA88 /* MediaSelectionGroupAVFObjC.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = MediaSelectionGroupAVFObjC.h; sourceTree = "<group>"; };
 		CDC1DD4117CC2C48008CB55D /* mediaControlsApple.css */ = {isa = PBXFileReference; lastKnownFileType = text.css; path = mediaControlsApple.css; sourceTree = "<group>"; };
@@ -16661,6 +16693,7 @@
 				A83B79080CCAFF2B000B0825 /* HTML */,
 				1C5FAECA0DCFD8C900D58F78 /* Inspector */,
 				AACC83D92316578600EB6BF5 /* MATHML */,
+				CD4E4E6A2357B526007895C3 /* MediaCapabilities */,
 				CDAB6D2A17C7E97D00C60B34 /* MediaControls */,
 				CD61FE7B1794CA02004101EB /* MediaSource */,
 				07CFD99317D01405001C4FFC /* MediaStream */,
@@ -22388,6 +22421,8 @@
 			isa = PBXGroup;
 			children = (
 				CDBD3D2B1FE85CBB0012C545 /* AudioConfiguration.h */,
+				CD4E4E9B2357CB9D007895C3 /* ColorGamut.h */,
+				CD4E4E9C2357CB9D007895C3 /* HdrMetadataType.h */,
 				CDCC9BCE22387E9A00FFB51C /* MediaCapabilitiesDecodingInfo.h */,
 				CDCC9BD022387EAA00FFB51C /* MediaCapabilitiesEncodingInfo.h */,
 				CD0C8B582141C8CA0062F59D /* MediaCapabilitiesInfo.h */,
@@ -22398,6 +22433,7 @@
 				CDBD3D3E1FE85CC30012C545 /* MediaEncodingType.h */,
 				9AC6F02221148F5100CBDA06 /* MediaEngineConfigurationFactory.cpp */,
 				9AC6F02521148F5400CBDA06 /* MediaEngineConfigurationFactory.h */,
+				CD4E4E9A2357CB9C007895C3 /* TransferFunction.h */,
 				CDBD3D341FE85CBF0012C545 /* VideoConfiguration.h */,
 			);
 			name = mediacapabilities;
@@ -25863,6 +25899,43 @@
 			path = ios;
 			sourceTree = "<group>";
 		};
+		CD4E4E6A2357B526007895C3 /* MediaCapabilities */ = {
+			isa = PBXGroup;
+			children = (
+				CD4E4E8D2357B602007895C3 /* JSAudioConfiguration.cpp */,
+				CD4E4E7C2357B5FD007895C3 /* JSAudioConfiguration.h */,
+				CD4E4E842357B5FF007895C3 /* JSColorGamut.cpp */,
+				CD4E4E862357B600007895C3 /* JSColorGamut.h */,
+				CD4E4E812357B5FE007895C3 /* JSHdrMetadataType.cpp */,
+				CD4E4E832357B5FF007895C3 /* JSHdrMetadataType.h */,
+				CD4E4E722357B558007895C3 /* JSMediaCapabilities.cpp */,
+				CD4E4E6F2357B557007895C3 /* JSMediaCapabilities.h */,
+				CD4E4E852357B5FF007895C3 /* JSMediaCapabilitiesDecodingInfo.cpp */,
+				CD4E4E6D2357B556007895C3 /* JSMediaCapabilitiesDecodingInfo.h */,
+				CD4E4E712357B557007895C3 /* JSMediaCapabilitiesEncodingInfo.cpp */,
+				CD4E4E6C2357B556007895C3 /* JSMediaCapabilitiesEncodingInfo.h */,
+				CD4E4E932357B604007895C3 /* JSMediaCapabilitiesInfo.cpp */,
+				CD4E4E702357B557007895C3 /* JSMediaCapabilitiesInfo.cpp */,
+				CD4E4E7D2357B5FD007895C3 /* JSMediaCapabilitiesInfo.h */,
+				CD4E4E6E2357B556007895C3 /* JSMediaCapabilitiesInfo.h */,
+				CD4E4E7E2357B5FD007895C3 /* JSMediaConfiguration.dep */,
+				CD4E4E872357B600007895C3 /* JSMediaConfiguration.h */,
+				CD4E4E892357B601007895C3 /* JSMediaDecodingConfiguration.cpp */,
+				CD4E4E822357B5FE007895C3 /* JSMediaDecodingConfiguration.h */,
+				CD4E4E902357B603007895C3 /* JSMediaDecodingType.cpp */,
+				CD4E4E882357B600007895C3 /* JSMediaDecodingType.h */,
+				CD4E4E802357B5FE007895C3 /* JSMediaEncodingConfiguration.cpp */,
+				CD4E4E912357B603007895C3 /* JSMediaEncodingConfiguration.h */,
+				CD4E4E8F2357B603007895C3 /* JSMediaEncodingType.cpp */,
+				CD4E4E8E2357B602007895C3 /* JSMediaEncodingType.h */,
+				CD4E4E8C2357B602007895C3 /* JSTransferFunction.cpp */,
+				CD4E4E7F2357B5FD007895C3 /* JSTransferFunction.h */,
+				CD4E4E992357BA8F007895C3 /* JSVideoConfiguration.cpp */,
+				CD4E4E972357BA8F007895C3 /* JSVideoConfiguration.h */,
+			);
+			name = MediaCapabilities;
+			sourceTree = "<group>";
+		};
 		CD61FE7B1794CA02004101EB /* MediaSource */ = {
 			isa = PBXGroup;
 			children = (
@@ -26066,6 +26139,8 @@
 			isa = PBXGroup;
 			children = (
 				CDBD3D3C1FE85CC20012C545 /* AudioConfiguration.idl */,
+				CDBD3D3F1FE85CC30012C545 /* ColorGamut.idl */,
+				CD4E4E602357B317007895C3 /* HdrMetadataType.idl */,
 				CDA130BD1FEB332D00F53254 /* MediaCapabilities.cpp */,
 				CDBD3D321FE85CBE0012C545 /* MediaCapabilities.h */,
 				CDBD3D2F1FE85CBC0012C545 /* MediaCapabilities.idl */,
@@ -26080,10 +26155,7 @@
 				CDA130BB1FEB332C00F53254 /* NavigatorMediaCapabilities.cpp */,
 				CDBD3D391FE85CC10012C545 /* NavigatorMediaCapabilities.h */,
 				CDBD3D311FE85CBE0012C545 /* NavigatorMediaCapabilities.idl */,
-				CDBD3D3A1FE85CC10012C545 /* ScreenColorGamut.h */,
-				CDBD3D3F1FE85CC30012C545 /* ScreenColorGamut.idl */,
-				CDBD3D2C1FE85CBB0012C545 /* ScreenLuminance.h */,
-				CDBD3D301FE85CBD0012C545 /* ScreenLuminance.idl */,
+				CD4E4E622357B3AD007895C3 /* TransferFunction.idl */,
 				CDBD3D281FE85CB80012C545 /* VideoConfiguration.idl */,
 			);
 			path = mediacapabilities;
diff --git a/Source/WebCore/bindings/scripts/CodeGenerator.pm b/Source/WebCore/bindings/scripts/CodeGenerator.pm
index 70eebd9..317e49a0 100644
--- a/Source/WebCore/bindings/scripts/CodeGenerator.pm
+++ b/Source/WebCore/bindings/scripts/CodeGenerator.pm
@@ -846,6 +846,8 @@
     $ret =~ s/Srgb/SRGB/ if $ret =~ /^Srgb/;
     $ret =~ s/Cenc/cenc/ if $ret =~ /^Cenc/;
     $ret =~ s/Cbcs/cbcs/ if $ret =~ /^Cbcs/;
+    $ret =~ s/Pq/PQ/ if $ret =~ /^Pq$/;
+    $ret =~ s/Hlg/HLG/ if $ret =~ /^Hlg/;
 
     return $ret;
 }
diff --git a/Source/WebCore/bindings/scripts/CodeGeneratorJS.pm b/Source/WebCore/bindings/scripts/CodeGeneratorJS.pm
index 1f4f755..0f25899 100644
--- a/Source/WebCore/bindings/scripts/CodeGeneratorJS.pm
+++ b/Source/WebCore/bindings/scripts/CodeGeneratorJS.pm
@@ -3677,6 +3677,7 @@
     $ret =~ s/cSS/css/ if $ret =~ /^cSS/;
     $ret =~ s/dOM/dom/ if $ret =~ /^dOM/;
     $ret =~ s/hTML/html/ if $ret =~ /^hTML/;
+    $ret =~ s/hDR/hdr/ if $ret =~ /^hDR/;
     $ret =~ s/jS/js/ if $ret =~ /^jS/;
     $ret =~ s/uRL/url/ if $ret =~ /^uRL/;
     $ret =~ s/xML/xml/ if $ret =~ /^xML/;
diff --git a/Source/WebCore/page/Settings.yaml b/Source/WebCore/page/Settings.yaml
index 35770af..dbb3d84 100644
--- a/Source/WebCore/page/Settings.yaml
+++ b/Source/WebCore/page/Settings.yaml
@@ -823,6 +823,10 @@
   type: bool
   initial: false
 
+hdrMediaCapabilitiesEnabled:
+  type: bool
+  initial: false
+
 clientCoordinatesRelativeToLayoutViewport:
   initial: false
   onChange: setNeedsRecalcStyleInAllFrames
diff --git a/Source/WebCore/platform/graphics/cocoa/HEVCUtilitiesCocoa.h b/Source/WebCore/platform/graphics/cocoa/HEVCUtilitiesCocoa.h
index 5216304..6b5cf1c 100644
--- a/Source/WebCore/platform/graphics/cocoa/HEVCUtilitiesCocoa.h
+++ b/Source/WebCore/platform/graphics/cocoa/HEVCUtilitiesCocoa.h
@@ -33,7 +33,7 @@
 
 struct MediaCapabilitiesInfo;
 
-extern bool validateHEVCParameters(HEVCParameterSet&, MediaCapabilitiesInfo&, bool hasAlphaChannel);
+extern bool validateHEVCParameters(HEVCParameterSet&, MediaCapabilitiesInfo&, bool hasAlphaChannel, bool hdrSupport);
 
 }
 
diff --git a/Source/WebCore/platform/graphics/cocoa/HEVCUtilitiesCocoa.mm b/Source/WebCore/platform/graphics/cocoa/HEVCUtilitiesCocoa.mm
index ae8854c..7ba06da 100644
--- a/Source/WebCore/platform/graphics/cocoa/HEVCUtilitiesCocoa.mm
+++ b/Source/WebCore/platform/graphics/cocoa/HEVCUtilitiesCocoa.mm
@@ -37,7 +37,7 @@
 
 namespace WebCore {
 
-bool validateHEVCParameters(HEVCParameterSet& parameters, MediaCapabilitiesInfo& info, bool hasAlphaChannel)
+bool validateHEVCParameters(HEVCParameterSet& parameters, MediaCapabilitiesInfo& info, bool hasAlphaChannel, bool hdrSupport)
 {
     CMVideoCodecType codec = kCMVideoCodecType_HEVC;
     if (hasAlphaChannel) {
@@ -50,6 +50,15 @@
 
         codec = codecCode.value().value;
     }
+
+    if (hdrSupport) {
+        // Platform supports HDR playback of HEVC Main10 Profile, as defined by ITU-T H.265 v6 (06/2019).
+        bool isMain10 = parameters.generalProfileSpace == 0
+            && (parameters.generalProfileIDC == 2 || parameters.generalProfileCompatibilityFlags == 1);
+        if (!isMain10)
+            return false;
+    }
+
     OSStatus status = VTSelectAndCreateVideoDecoderInstance(codec, kCFAllocatorDefault, nullptr, nullptr);
     if (status != noErr)
         return false;
diff --git a/Source/WebCore/platform/graphics/cocoa/MediaEngineConfigurationFactoryCocoa.cpp b/Source/WebCore/platform/graphics/cocoa/MediaEngineConfigurationFactoryCocoa.cpp
index aef7695..bc9056f 100644
--- a/Source/WebCore/platform/graphics/cocoa/MediaEngineConfigurationFactoryCocoa.cpp
+++ b/Source/WebCore/platform/graphics/cocoa/MediaEngineConfigurationFactoryCocoa.cpp
@@ -76,16 +76,17 @@
             return;
         }
 
+        bool hdrSupported = videoConfiguration.colorGamut || videoConfiguration.hdrMetadataType || videoConfiguration.transferFunction;
         bool alphaChannel = videoConfiguration.alphaChannel && videoConfiguration.alphaChannel.value();
 
         if (videoCodecType == kCMVideoCodecType_HEVC) {
             auto parameters = parseHEVCCodecParameters(codec);
-            if (!parameters || !validateHEVCParameters(parameters.value(), info, alphaChannel)) {
+            if (!parameters || !validateHEVCParameters(parameters.value(), info, alphaChannel, hdrSupported)) {
                 callback({{ }, WTFMove(configuration)});
                 return;
             }
         } else {
-            if (alphaChannel) {
+            if (alphaChannel || hdrSupported) {
                 callback({{ }, WTFMove(configuration)});
                 return;
             }
diff --git a/Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.h b/Source/WebCore/platform/mediacapabilities/ColorGamut.h
similarity index 97%
rename from Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.h
rename to Source/WebCore/platform/mediacapabilities/ColorGamut.h
index a16329b..1813e35 100644
--- a/Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.h
+++ b/Source/WebCore/platform/mediacapabilities/ColorGamut.h
@@ -27,7 +27,7 @@
 
 namespace WebCore {
 
-enum class ScreenColorGamut {
+enum class ColorGamut {
     SRGB,
     P3,
     Rec2020,
diff --git a/Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.h b/Source/WebCore/platform/mediacapabilities/HdrMetadataType.h
similarity index 90%
copy from Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.h
copy to Source/WebCore/platform/mediacapabilities/HdrMetadataType.h
index a16329b..65c1d0e 100644
--- a/Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.h
+++ b/Source/WebCore/platform/mediacapabilities/HdrMetadataType.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2016 Apple Inc. All rights reserved.
+ * Copyright (C) 2019 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -27,10 +27,10 @@
 
 namespace WebCore {
 
-enum class ScreenColorGamut {
-    SRGB,
-    P3,
-    Rec2020,
+enum class HdrMetadataType {
+    SmpteSt2086,
+    SmpteSt209410,
+    SmpteSt209440
 };
 
 } // namespace WebCore
diff --git a/Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.h b/Source/WebCore/platform/mediacapabilities/TransferFunction.h
similarity index 92%
copy from Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.h
copy to Source/WebCore/platform/mediacapabilities/TransferFunction.h
index a16329b..b145b3a 100644
--- a/Source/WebCore/Modules/mediacapabilities/ScreenColorGamut.h
+++ b/Source/WebCore/platform/mediacapabilities/TransferFunction.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2016 Apple Inc. All rights reserved.
+ * Copyright (C) 2019 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -27,10 +27,10 @@
 
 namespace WebCore {
 
-enum class ScreenColorGamut {
+enum class TransferFunction {
     SRGB,
-    P3,
-    Rec2020,
+    PQ,
+    HLG
 };
 
 } // namespace WebCore
diff --git a/Source/WebCore/platform/mediacapabilities/VideoConfiguration.h b/Source/WebCore/platform/mediacapabilities/VideoConfiguration.h
index 745f8b8..cd9dca3 100644
--- a/Source/WebCore/platform/mediacapabilities/VideoConfiguration.h
+++ b/Source/WebCore/platform/mediacapabilities/VideoConfiguration.h
@@ -25,6 +25,9 @@
 
 #pragma once
 
+#include "ColorGamut.h"
+#include "HdrMetadataType.h"
+#include "TransferFunction.h"
 #include <wtf/Optional.h>
 #include <wtf/text/WTFString.h>
 
@@ -37,6 +40,9 @@
     uint64_t bitrate;
     double framerate;
     Optional<bool> alphaChannel;
+    Optional<ColorGamut> colorGamut;
+    Optional<HdrMetadataType> hdrMetadataType;
+    Optional<TransferFunction> transferFunction;
 };
 
 }
diff --git a/Source/WebCore/platform/mock/MediaEngineConfigurationFactoryMock.cpp b/Source/WebCore/platform/mock/MediaEngineConfigurationFactoryMock.cpp
index eadb072..768836a 100644
--- a/Source/WebCore/platform/mock/MediaEngineConfigurationFactoryMock.cpp
+++ b/Source/WebCore/platform/mock/MediaEngineConfigurationFactoryMock.cpp
@@ -49,7 +49,13 @@
 
     // Only the "mock-with-alpha" codec supports alphaChannel
     if (videoConfig && videoConfig->alphaChannel && videoConfig->alphaChannel.value()) {
-        if (ContentType(videoConfig->contentType).codecsParameter() != "mock-with-alpha")
+        if (ContentType(videoConfig->contentType).parameter(ContentType::codecsParameter()) != "mock-with-alpha")
+            return false;
+    }
+
+    // Only the "mock-with-hdr" codec supports HDR)
+    if (videoConfig && (videoConfig->colorGamut || videoConfig->hdrMetadataType || videoConfig->transferFunction)) {
+        if (ContentType(videoConfig->contentType).parameter(ContentType::codecsParameter()) != "mock-with-hdr")
             return false;
     }
 
@@ -100,7 +106,7 @@
 
     // Only the "mock-with-alpha" codec supports alphaChannel
     if (videoConfig && videoConfig->alphaChannel && videoConfig->alphaChannel.value()) {
-        if (ContentType(videoConfig->contentType).codecsParameter() != "mock-with-alpha")
+        if (ContentType(videoConfig->contentType).parameter(ContentType::codecsParameter()) != "mock-with-alpha")
             return false;
     }
 
diff --git a/Source/WebKit/ChangeLog b/Source/WebKit/ChangeLog
index 386eaaa..ca39a38 100644
--- a/Source/WebKit/ChangeLog
+++ b/Source/WebKit/ChangeLog
@@ -1,3 +1,14 @@
+2019-10-18  Jer Noble  <jer.noble@apple.com>
+
+        Add experimental HDR MediaCapabilities support.
+        https://bugs.webkit.org/show_bug.cgi?id=203113
+
+        Reviewed by Eric Carlson.
+
+        Add experimental hdrMediaCapabilitiesEnabled preference.
+
+        * Shared/WebPreferences.yaml:
+
 2019-10-18  Jiewen Tan  <jiewen_tan@apple.com>
 
         [WebAuthn] Implement AuthenticatorCancel
diff --git a/Source/WebKit/Shared/WebPreferences.yaml b/Source/WebKit/Shared/WebPreferences.yaml
index 76c6b00..ef16776 100644
--- a/Source/WebKit/Shared/WebPreferences.yaml
+++ b/Source/WebKit/Shared/WebPreferences.yaml
@@ -1413,6 +1413,13 @@
   humanReadableDescription: "Media Capabilities Extensions"
   category: experimental
 
+HDRMediaCapabilitiesEnabled:
+  type: bool
+  defaultValue: false
+  humanReadableName: "HDR Media Capabilities"
+  humanReadableDescription: "HDR Media Capabilities"
+  category: experimental
+
 ResizeObserverEnabled:
   type: bool
   defaultValue: false