From f7ce00687aa9f45cecb43210d6233716398f5eb5 Mon Sep 17 00:00:00 2001
From: Majid Valipour <majidvp@chromium.org>
Date: Fri, 6 Oct 2017 00:24:40 -0400
Subject: [PATCH 01/11] Add basic image encoding with limited format

---
 lib/ui/BUILD.gn                   |   2 +
 lib/ui/dart_ui.cc                 |   2 +
 lib/ui/painting.dart              |  20 +++++
 lib/ui/painting/image_encoding.cc | 136 ++++++++++++++++++++++++++++++
 lib/ui/painting/image_encoding.h  |  19 +++++
 5 files changed, 179 insertions(+)
 create mode 100644 lib/ui/painting/image_encoding.cc
 create mode 100644 lib/ui/painting/image_encoding.h

diff --git a/lib/ui/BUILD.gn b/lib/ui/BUILD.gn
index 2862a9b68cf96..8b3be72d5973b 100644
--- a/lib/ui/BUILD.gn
+++ b/lib/ui/BUILD.gn
@@ -24,6 +24,8 @@ source_set("ui") {
     "painting/gradient.h",
     "painting/image.cc",
     "painting/image.h",
+    "painting/image_encoding.cc",
+    "painting/image_encoding.h",
     "painting/image_filter.cc",
     "painting/image_filter.h",
     "painting/image_shader.cc",
diff --git a/lib/ui/dart_ui.cc b/lib/ui/dart_ui.cc
index 59d083a191778..5cc2b07976d46 100644
--- a/lib/ui/dart_ui.cc
+++ b/lib/ui/dart_ui.cc
@@ -12,6 +12,7 @@
 #include "flutter/lib/ui/painting/frame_info.h"
 #include "flutter/lib/ui/painting/gradient.h"
 #include "flutter/lib/ui/painting/image.h"
+#include "flutter/lib/ui/painting/image_encoding.h"
 #include "flutter/lib/ui/painting/image_filter.h"
 #include "flutter/lib/ui/painting/image_shader.h"
 #include "flutter/lib/ui/painting/path.h"
@@ -56,6 +57,7 @@ void DartUI::InitForGlobal() {
     Codec::RegisterNatives(g_natives);
     DartRuntimeHooks::RegisterNatives(g_natives);
     FrameInfo::RegisterNatives(g_natives);
+    ImageEncoding::RegisterNatives(g_natives);
     ImageFilter::RegisterNatives(g_natives);
     ImageShader::RegisterNatives(g_natives);
     Paragraph::RegisterNatives(g_natives);
diff --git a/lib/ui/painting.dart b/lib/ui/painting.dart
index 4b041a27df3eb..f961a99ac4a6b 100644
--- a/lib/ui/painting.dart
+++ b/lib/ui/painting.dart
@@ -1316,6 +1316,26 @@ Future<Null> _decodeImageFromListAsync(Uint8List list, ImageDecoderCallback call
   callback(frameInfo.image);
 }
 
+/// The encoding formats supported by the [encodeImage].
+enum EncodedImageFormat {
+  // Be conservative with the formats we expose. We can increase the list in future but reducing
+  // it is more difficult.
+  JPEG,
+  PNG,
+  WEBP,
+}
+
+/// Callback signature for [encodeImage].
+typedef void ImageEncoderCallback(Uint8List result);
+
+/// Convert an [Image] object into a byte array/
+///
+/// [format] is encoding format to be used.
+///
+/// [quality] is a value in [0, 100] where 0 corresponds to the lowest quality.
+void encodeImage(Image image, EncodedImageFormat format, int quality, ImageEncoderCallback callback)
+    native "encodeImage";
+
 /// Determines the winding rule that decides how the interior of a [Path] is
 /// calculated.
 ///
diff --git a/lib/ui/painting/image_encoding.cc b/lib/ui/painting/image_encoding.cc
new file mode 100644
index 0000000000000..27622d3c68c5b
--- /dev/null
+++ b/lib/ui/painting/image_encoding.cc
@@ -0,0 +1,136 @@
+// Copyright 2018 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "flutter/lib/ui/painting/image_encoding.h"
+
+#include "flutter/common/threads.h"
+#include "flutter/lib/ui/painting/image.h"
+#include "flutter/lib/ui/painting/resource_context.h"
+#include "lib/fxl/build_config.h"
+#include "lib/fxl/functional/make_copyable.h"
+#include "lib/tonic/dart_persistent_value.h"
+#include "lib/tonic/dart_state.h"
+#include "lib/tonic/logging/dart_invoke.h"
+#include "lib/tonic/typed_data/uint8_list.h"
+#include "third_party/skia/include/core/SkEncodedImageFormat.h"
+#include "third_party/skia/include/core/SkImage.h"
+
+using tonic::DartInvoke;
+using tonic::DartPersistentValue;
+using tonic::ToDart;
+
+namespace blink {
+namespace {
+
+void InvokeDataCallback(std::unique_ptr<DartPersistentValue> callback,
+                        sk_sp<SkData> buffer) {
+  tonic::DartState* dart_state = callback->dart_state().get();
+  if (!dart_state) {
+    return;
+  }
+  tonic::DartState::Scope scope(dart_state);
+  if (!buffer) {
+    DartInvoke(callback->value(), {Dart_Null()});
+  } else {
+    Dart_Handle dart_data = tonic::DartConverter<tonic::Uint8List>::ToDart(
+        buffer->bytes(), buffer->size());
+    DartInvoke(callback->value(), {dart_data});
+  }
+}
+
+sk_sp<SkData> EncodeImage(sk_sp<SkImage> image,
+                          SkEncodedImageFormat format,
+                          int quality) {
+  if (image == nullptr) {
+    return nullptr;
+  }
+  return image->encodeToData(format, quality);
+}
+
+void EncodeImageAndInvokeDataCallback(
+    std::unique_ptr<DartPersistentValue> callback,
+    sk_sp<SkImage> image,
+    SkEncodedImageFormat format,
+    int quality) {
+  sk_sp<SkData> encoded = EncodeImage(std::move(image), format, quality);
+
+  Threads::UI()->PostTask(
+      fxl::MakeCopyable([callback = std::move(callback), encoded]() mutable {
+        InvokeDataCallback(std::move(callback), std::move(encoded));
+      }));
+}
+
+SkEncodedImageFormat ToSkEncodedImageFormat(int format) {
+  // Map the formats exposed in flutter to formats supported in Skia.
+  // See:
+  // https://github.com/google/skia/blob/master/include/core/SkEncodedImageFormat.h
+  switch (format) {
+    case 0:
+      return SkEncodedImageFormat::kJPEG;
+    case 1:
+      return SkEncodedImageFormat::kPNG;
+    case 2:
+      return SkEncodedImageFormat::kWEBP;
+    default:
+      /* NOTREACHED */
+      return SkEncodedImageFormat::kWEBP;
+  }
+}
+
+void EncodeImage(Dart_NativeArguments args) {
+  Dart_Handle exception = nullptr;
+
+  CanvasImage* canvas_image =
+      tonic::DartConverter<CanvasImage*>::FromArguments(args, 0, exception);
+
+  if (exception) {
+    Dart_ThrowException(exception);
+    return;
+  }
+  if (!canvas_image)
+    Dart_ThrowException(ToDart("encodeImage called with non-genuine Image."));
+
+  int format = tonic::DartConverter<int>::FromArguments(args, 1, exception);
+  if (exception) {
+    Dart_ThrowException(exception);
+    return;
+  }
+  SkEncodedImageFormat image_format = ToSkEncodedImageFormat(format);
+
+  int quality = tonic::DartConverter<int>::FromArguments(args, 2, exception);
+  if (exception) {
+    Dart_ThrowException(exception);
+    return;
+  }
+  if (quality > 100)
+    quality = 100;
+  if (quality < 0)
+    quality = 0;
+
+  Dart_Handle callback_handle = Dart_GetNativeArgument(args, 3);
+  if (!Dart_IsClosure(callback_handle)) {
+    Dart_ThrowException(ToDart("Callback must be a function"));
+    return;
+  }
+
+  auto callback = std::make_unique<DartPersistentValue>(
+      tonic::DartState::Current(), callback_handle);
+  sk_sp<SkImage> image = canvas_image->image();
+
+  Threads::IO()->PostTask(fxl::MakeCopyable(
+      [callback = std::move(callback), image, image_format, quality]() mutable {
+        EncodeImageAndInvokeDataCallback(std::move(callback), std::move(image),
+                                         image_format, quality);
+      }));
+}
+
+}  // namespace
+
+void ImageEncoding::RegisterNatives(tonic::DartLibraryNatives* natives) {
+  natives->Register({
+      {"encodeImage", EncodeImage, 4, true},
+  });
+}
+
+}  // namespace blink
diff --git a/lib/ui/painting/image_encoding.h b/lib/ui/painting/image_encoding.h
new file mode 100644
index 0000000000000..b716458131099
--- /dev/null
+++ b/lib/ui/painting/image_encoding.h
@@ -0,0 +1,19 @@
+// Copyright 2018 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef FLUTTER_LIB_UI_PAINTING_IMAGE_ENCODING_H_
+#define FLUTTER_LIB_UI_PAINTING_IMAGE_ENCODING_H_
+
+#include "lib/tonic/dart_library_natives.h"
+
+namespace blink {
+
+class ImageEncoding {
+ public:
+  static void RegisterNatives(tonic::DartLibraryNatives* natives);
+};
+
+}  // namespace blink
+
+#endif  // FLUTTER_LIB_UI_PAINTING_IMAGE_ENCODING_H_

From 5472da98e5be69e54db78317f375cfca88cabf0e Mon Sep 17 00:00:00 2001
From: Majid Valipour <majidvp@chromium.org>
Date: Thu, 8 Mar 2018 22:20:47 -0500
Subject: [PATCH 02/11] prefer single quote

---
 lib/ui/painting.dart | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/ui/painting.dart b/lib/ui/painting.dart
index f961a99ac4a6b..57661dbc60688 100644
--- a/lib/ui/painting.dart
+++ b/lib/ui/painting.dart
@@ -1334,7 +1334,7 @@ typedef void ImageEncoderCallback(Uint8List result);
 ///
 /// [quality] is a value in [0, 100] where 0 corresponds to the lowest quality.
 void encodeImage(Image image, EncodedImageFormat format, int quality, ImageEncoderCallback callback)
-    native "encodeImage";
+    native 'encodeImage';
 
 /// Determines the winding rule that decides how the interior of a [Path] is
 /// calculated.

From a4e3b63c211addac3bf2e8d6fed92b92f65165e5 Mon Sep 17 00:00:00 2001
From: Majid Valipour <majidvp@chromium.org>
Date: Sun, 1 Apr 2018 12:57:11 -0400
Subject: [PATCH 03/11] Address review feedback including:

- Add tests
- Move to make encode a method of Image
- futurize
- Avoid using Dart_ThrowException instead use return value
- Improve formatting and comments
---
 lib/ui/dart_ui.cc                 |   1 -
 lib/ui/painting.dart              |  47 +++++++++++++----------
 lib/ui/painting/image.cc          |   8 ++++
 lib/ui/painting/image.h           |   2 +
 lib/ui/painting/image_encoding.cc |  43 +++++----------------
 lib/ui/painting/image_encoding.h  |  10 +++--
 testing/dart/encoding_test.dart   |  61 ++++++++++++++++++++++++++++++
 testing/resources/square-80.jpg   | Bin 0 -> 928 bytes
 testing/resources/square-80.png   | Bin 0 -> 125 bytes
 testing/resources/square-80.webp  | Bin 0 -> 666 bytes
 testing/run_tests.sh              |   8 ++--
 11 files changed, 118 insertions(+), 62 deletions(-)
 create mode 100644 testing/dart/encoding_test.dart
 create mode 100644 testing/resources/square-80.jpg
 create mode 100644 testing/resources/square-80.png
 create mode 100644 testing/resources/square-80.webp

diff --git a/lib/ui/dart_ui.cc b/lib/ui/dart_ui.cc
index 5cc2b07976d46..25b5bdf44a95d 100644
--- a/lib/ui/dart_ui.cc
+++ b/lib/ui/dart_ui.cc
@@ -57,7 +57,6 @@ void DartUI::InitForGlobal() {
     Codec::RegisterNatives(g_natives);
     DartRuntimeHooks::RegisterNatives(g_natives);
     FrameInfo::RegisterNatives(g_natives);
-    ImageEncoding::RegisterNatives(g_natives);
     ImageFilter::RegisterNatives(g_natives);
     ImageShader::RegisterNatives(g_natives);
     Paragraph::RegisterNatives(g_natives);
diff --git a/lib/ui/painting.dart b/lib/ui/painting.dart
index 57661dbc60688..95b021c32576d 100644
--- a/lib/ui/painting.dart
+++ b/lib/ui/painting.dart
@@ -1196,6 +1196,16 @@ class Paint {
   }
 }
 
+/// The encoding formats supported by the [Image.toByteData].
+// These enum values must be kept in sync with the logic in ToSkEncodedImageFormat.
+enum EncodeFormat {
+  // Be conservative with the formats we expose. It is easy to add new formats in future but
+  // difficult to remove.
+  JPEG,
+  PNG,
+  WEBP,
+}
+
 /// Opaque handle to raw decoded image data (pixels).
 ///
 /// To obtain an [Image] object, use [instantiateImageCodec].
@@ -1215,6 +1225,23 @@ class Image extends NativeFieldWrapperClass2 {
   /// The number of image pixels along the image's vertical axis.
   int get height native 'Image_height';
 
+  /// Converts the [Image] object into a byte array.
+  ///
+  /// The [format] is encoding format to be used.
+  ///
+  /// The [quality] is a value in the range 0 to 100 where 0 corresponds to the lowest quality.
+  ///
+  /// Returns a future which complete with the binary image data (e.g a PNG or JPEG binary data) or
+  /// an error if encoding fails.
+  Future<Uint8List> toByteData({EncodeFormat format: EncodeFormat.JPEG, int quality: 80}) {
+    return _futurize(
+          (_Callback<Uint8List> callback) => _toByteData(format.index, quality, callback)
+    );
+  }
+
+  /// Returns an error message on failure, null on success.
+  String _toByteData(int format, int quality, _Callback<Uint8List> callback) native 'Image_toByteData';
+
   /// Release the resources used by this object. The object is no longer usable
   /// after this method is called.
   void dispose() native 'Image_dispose';
@@ -1316,26 +1343,6 @@ Future<Null> _decodeImageFromListAsync(Uint8List list, ImageDecoderCallback call
   callback(frameInfo.image);
 }
 
-/// The encoding formats supported by the [encodeImage].
-enum EncodedImageFormat {
-  // Be conservative with the formats we expose. We can increase the list in future but reducing
-  // it is more difficult.
-  JPEG,
-  PNG,
-  WEBP,
-}
-
-/// Callback signature for [encodeImage].
-typedef void ImageEncoderCallback(Uint8List result);
-
-/// Convert an [Image] object into a byte array/
-///
-/// [format] is encoding format to be used.
-///
-/// [quality] is a value in [0, 100] where 0 corresponds to the lowest quality.
-void encodeImage(Image image, EncodedImageFormat format, int quality, ImageEncoderCallback callback)
-    native 'encodeImage';
-
 /// Determines the winding rule that decides how the interior of a [Path] is
 /// calculated.
 ///
diff --git a/lib/ui/painting/image.cc b/lib/ui/painting/image.cc
index 0b0127cd0c6c2..db8a227bb44c5 100644
--- a/lib/ui/painting/image.cc
+++ b/lib/ui/painting/image.cc
@@ -5,6 +5,7 @@
 #include "flutter/lib/ui/painting/image.h"
 
 #include "flutter/common/threads.h"
+#include "flutter/lib/ui/painting/image_encoding.h"
 #include "flutter/lib/ui/painting/utils.h"
 #include "lib/tonic/converter/dart_converter.h"
 #include "lib/tonic/dart_args.h"
@@ -20,6 +21,7 @@ IMPLEMENT_WRAPPERTYPEINFO(ui, Image);
 #define FOR_EACH_BINDING(V) \
   V(Image, width)           \
   V(Image, height)          \
+  V(Image, toByteData)      \
   V(Image, dispose)
 
 FOR_EACH_BINDING(DART_NATIVE_CALLBACK)
@@ -36,6 +38,12 @@ CanvasImage::~CanvasImage() {
   SkiaUnrefOnIOThread(&image_);
 }
 
+Dart_Handle CanvasImage::toByteData(int format,
+                                    int quality,
+                                    Dart_Handle callback_handle) {
+  return EncodeImage(this, format, quality, callback_handle);
+}
+
 void CanvasImage::dispose() {
   ClearDartWrapper();
 }
diff --git a/lib/ui/painting/image.h b/lib/ui/painting/image.h
index 8ad11660721f0..69d63cca51b84 100644
--- a/lib/ui/painting/image.h
+++ b/lib/ui/painting/image.h
@@ -27,6 +27,8 @@ class CanvasImage final : public fxl::RefCountedThreadSafe<CanvasImage>,
 
   int width() { return image_->width(); }
   int height() { return image_->height(); }
+  Dart_Handle toByteData(int format, int quality, Dart_Handle callback);
+
   void dispose();
 
   const sk_sp<SkImage>& image() const { return image_; }
diff --git a/lib/ui/painting/image_encoding.cc b/lib/ui/painting/image_encoding.cc
index 27622d3c68c5b..f356e955f6745 100644
--- a/lib/ui/painting/image_encoding.cc
+++ b/lib/ui/painting/image_encoding.cc
@@ -78,42 +78,25 @@ SkEncodedImageFormat ToSkEncodedImageFormat(int format) {
   }
 }
 
-void EncodeImage(Dart_NativeArguments args) {
-  Dart_Handle exception = nullptr;
-
-  CanvasImage* canvas_image =
-      tonic::DartConverter<CanvasImage*>::FromArguments(args, 0, exception);
+}  // namespace
 
-  if (exception) {
-    Dart_ThrowException(exception);
-    return;
-  }
+Dart_Handle EncodeImage(CanvasImage* canvas_image,
+                        int format,
+                        int quality,
+                        Dart_Handle callback_handle) {
   if (!canvas_image)
-    Dart_ThrowException(ToDart("encodeImage called with non-genuine Image."));
+    return ToDart("encode called with non-genuine Image.");
+
+  if (!Dart_IsClosure(callback_handle))
+    return ToDart("Callback must be a function.");
 
-  int format = tonic::DartConverter<int>::FromArguments(args, 1, exception);
-  if (exception) {
-    Dart_ThrowException(exception);
-    return;
-  }
   SkEncodedImageFormat image_format = ToSkEncodedImageFormat(format);
 
-  int quality = tonic::DartConverter<int>::FromArguments(args, 2, exception);
-  if (exception) {
-    Dart_ThrowException(exception);
-    return;
-  }
   if (quality > 100)
     quality = 100;
   if (quality < 0)
     quality = 0;
 
-  Dart_Handle callback_handle = Dart_GetNativeArgument(args, 3);
-  if (!Dart_IsClosure(callback_handle)) {
-    Dart_ThrowException(ToDart("Callback must be a function"));
-    return;
-  }
-
   auto callback = std::make_unique<DartPersistentValue>(
       tonic::DartState::Current(), callback_handle);
   sk_sp<SkImage> image = canvas_image->image();
@@ -123,14 +106,8 @@ void EncodeImage(Dart_NativeArguments args) {
         EncodeImageAndInvokeDataCallback(std::move(callback), std::move(image),
                                          image_format, quality);
       }));
-}
-
-}  // namespace
 
-void ImageEncoding::RegisterNatives(tonic::DartLibraryNatives* natives) {
-  natives->Register({
-      {"encodeImage", EncodeImage, 4, true},
-  });
+  return Dart_Null();
 }
 
 }  // namespace blink
diff --git a/lib/ui/painting/image_encoding.h b/lib/ui/painting/image_encoding.h
index b716458131099..a121d597ccefd 100644
--- a/lib/ui/painting/image_encoding.h
+++ b/lib/ui/painting/image_encoding.h
@@ -9,10 +9,12 @@
 
 namespace blink {
 
-class ImageEncoding {
- public:
-  static void RegisterNatives(tonic::DartLibraryNatives* natives);
-};
+class CanvasImage;
+
+Dart_Handle EncodeImage(CanvasImage* canvas_image,
+                        int format,
+                        int quality,
+                        Dart_Handle callback_handle);
 
 }  // namespace blink
 
diff --git a/testing/dart/encoding_test.dart b/testing/dart/encoding_test.dart
new file mode 100644
index 0000000000000..9848358154bf5
--- /dev/null
+++ b/testing/dart/encoding_test.dart
@@ -0,0 +1,61 @@
+// Copyright 2018 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+import 'dart:ui';
+import 'dart:typed_data';
+import 'dart:io';
+
+import 'package:test/test.dart';
+import 'package:path/path.dart' as path;
+
+void main() {
+
+  Image createSquareTestImage() {
+    PictureRecorder recorder = new PictureRecorder();
+    Canvas canvas = new Canvas(recorder, new Rect.fromLTWH(0.0, 0.0, 10.0, 10.0));
+
+    var black = new Paint()
+      ..strokeWidth = 1.0
+      ..color = const Color.fromRGBO(0, 0, 0, 1.0);
+    var green = new Paint()
+      ..strokeWidth = 1.0
+      ..color = const Color.fromRGBO(0, 255, 0, 1.0);
+
+    canvas.drawRect(new Rect.fromLTWH(0.0, 0.0, 10.0, 10.0), black);
+    canvas.drawRect(new Rect.fromLTWH(2.0, 2.0, 6.0, 6.0), green);
+    return recorder.endRecording().toImage(10, 10);
+  }
+
+  Uint8List readFile(fileName) {
+    final file = new File(path.join('flutter', 'testing', 'resources', fileName));
+    return file.readAsBytesSync();
+  }
+
+  final Image testImage = createSquareTestImage();
+
+  test('Encode with default arguments', () async {
+    Uint8List data = await testImage.toByteData();
+    Uint8List expected = readFile('square-80.jpg');
+    expect(data, expected);
+  });
+
+  test('Encode JPEG', () async {
+    Uint8List data = await testImage.toByteData(format: EncodeFormat.JPEG, quality:80);
+    Uint8List expected = readFile('square-80.jpg');
+    expect(data, expected);
+  });
+
+  test('Encode PNG', () async {
+    Uint8List data = await testImage.toByteData(format: EncodeFormat.PNG, quality: 80);
+    Uint8List expected = readFile('square-80.png');
+    expect(data, expected);
+  });
+
+  test('Encode WEBP', () async {
+    Uint8List data = await testImage.toByteData(format: EncodeFormat.WEBP, quality: 80);
+    Uint8List expected = readFile('square-80.webp');
+    expect(data, expected);
+  });
+}
\ No newline at end of file
diff --git a/testing/resources/square-80.jpg b/testing/resources/square-80.jpg
new file mode 100644
index 0000000000000000000000000000000000000000..1140c33bd39039758e39b057c1da6ea0746bee4e
GIT binary patch
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diff --git a/testing/resources/square-80.png b/testing/resources/square-80.png
new file mode 100644
index 0000000000000000000000000000000000000000..a042cece5516363a3d4c81eb781e5ced2456df80
GIT binary patch
literal 125
zcmeAS@N?(olHy`uVBq!ia0vp^AT}2V8<6ZZI=>f4F%}28J29*~C-V}>VJUX<4B-HR
z8jh3>AYa|n#W6%;YH~_K!jJO~ED1_(g3Lg`J*V|_jGK_J3>TNA<O<n71`}RpVa*M?
Qen2e@p00i_>zopr06J_NxBvhE

literal 0
HcmV?d00001

diff --git a/testing/resources/square-80.webp b/testing/resources/square-80.webp
new file mode 100644
index 0000000000000000000000000000000000000000..fe3924cad729ba651481c25c3b80c15db695a26c
GIT binary patch
literal 666
zcmWIYbaR`;#J~{l>J$(bU=hK^z`&pY#GGK{>FgXJ0hDE6V3Gin0t^hfc_l?b?oJ93
zkx>dDF&IcpE-rwvvCxbR4BxIX07(Xh%eq+P2?=qgq!uRw6@38Wk|Lnx3=E7ZK(<Ia
zgk1q*CqdXfAa+qmkTX!t0w7x>9f_TU#4ax>C;_TD0aBk_Py}M%0kUm!b4o#WfdI(G
zJgIr1!9Y3!h-Dax8G;zx8JvJ@sscoK<}YSou=vKnz&sHlmNbQdVS6hBgTx(#n94#1
z27aK}wkrjRMTua?umDM>v@`~WPs<q?cq17YgfB2Ka7Du$iqMOQ3mkq`0P2we`ZFI0
z(;0FYQW+E&JQ?yBk{R@XEF%U3215ojV2V))0V)h&VwlUQ#l^tI!04c+x`FA9frHJ&
z##P))BODn1{r&diuiO83?0;n5Pu;gH@%x`!-Syq4&i^a_`%3q3Z0-I((YIGmssEe#
U@4V_ix#lD9FWqM|H*a770E!QDU;qFB

literal 0
HcmV?d00001

diff --git a/testing/run_tests.sh b/testing/run_tests.sh
index e84ce1c5509f1..70b02e3537eb8 100755
--- a/testing/run_tests.sh
+++ b/testing/run_tests.sh
@@ -2,11 +2,11 @@
 
 set -ex
 
-out/host_debug_unopt/fxl_unittests
-out/host_debug_unopt/synchronization_unittests
-out/host_debug_unopt/wtf_unittests
+#out/host_debug_unopt/fxl_unittests
+#out/host_debug_unopt/synchronization_unittests
+#out/host_debug_unopt/wtf_unittests
 
-flutter/travis/analyze.sh
+#flutter/travis/analyze.sh
 
 pushd flutter/testing/dart
 pub get

From 4a39f8dd23324ca74bf641cfc42fa75ca22c9d47 Mon Sep 17 00:00:00 2001
From: Majid Valipour <majidvp@chromium.org>
Date: Sun, 1 Apr 2018 14:59:14 -0400
Subject: [PATCH 04/11] Revert changes to run_tests

---
 testing/run_tests.sh | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/testing/run_tests.sh b/testing/run_tests.sh
index 70b02e3537eb8..e84ce1c5509f1 100755
--- a/testing/run_tests.sh
+++ b/testing/run_tests.sh
@@ -2,11 +2,11 @@
 
 set -ex
 
-#out/host_debug_unopt/fxl_unittests
-#out/host_debug_unopt/synchronization_unittests
-#out/host_debug_unopt/wtf_unittests
+out/host_debug_unopt/fxl_unittests
+out/host_debug_unopt/synchronization_unittests
+out/host_debug_unopt/wtf_unittests
 
-#flutter/travis/analyze.sh
+flutter/travis/analyze.sh
 
 pushd flutter/testing/dart
 pub get

From 447d8d511cf81a5e01278b498aa178b8d6a1d488 Mon Sep 17 00:00:00 2001
From: Majid Valipour <majidvp@chromium.org>
Date: Sun, 1 Apr 2018 15:18:49 -0400
Subject: [PATCH 05/11] Update quality documentation

---
 lib/ui/painting.dart | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/ui/painting.dart b/lib/ui/painting.dart
index 95b021c32576d..be6e12dcac481 100644
--- a/lib/ui/painting.dart
+++ b/lib/ui/painting.dart
@@ -1229,7 +1229,9 @@ class Image extends NativeFieldWrapperClass2 {
   ///
   /// The [format] is encoding format to be used.
   ///
-  /// The [quality] is a value in the range 0 to 100 where 0 corresponds to the lowest quality.
+  /// The [quality] is a value in the range 0 to 100. [quality] is a format specific metric trading
+  /// off size and encoding error. When used, 100 encodes with highest quality (i.e., least error)
+  /// and 0 encodes with lowest quality (i.e., smallest size).
   ///
   /// Returns a future which complete with the binary image data (e.g a PNG or JPEG binary data) or
   /// an error if encoding fails.

From 2ecab34190273f3c545fbd4b1be70afef6bf8e05 Mon Sep 17 00:00:00 2001
From: Majid Valipour <majidvp@chromium.org>
Date: Sun, 1 Apr 2018 15:39:09 -0400
Subject: [PATCH 06/11] Update license file to make Travis happy

---
 travis/licenses_golden/licenses_flutter | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/travis/licenses_golden/licenses_flutter b/travis/licenses_golden/licenses_flutter
index 7de50c115fd76..8749f6880dbf4 100644
--- a/travis/licenses_golden/licenses_flutter
+++ b/travis/licenses_golden/licenses_flutter
@@ -1642,6 +1642,8 @@ ORIGIN: ../../../flutter/assets/asset_provider.h + ../../../LICENSE
 TYPE: LicenseType.bsd
 FILE: ../../../flutter/assets/asset_provider.h
 FILE: ../../../flutter/flutter_kernel_transformers/lib/track_widget_constructor_locations.dart
+FILE: ../../../flutter/lib/ui/painting/image_encoding.cc
+FILE: ../../../flutter/lib/ui/painting/image_encoding.h
 FILE: ../../../flutter/shell/platform/android/apk_asset_provider.h
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/accessibility_text_entry.h
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/accessibility_text_entry.mm

From 7202b1624acbd9e4476ba7a5dcd73c0bd8aadd9c Mon Sep 17 00:00:00 2001
From: Majid Valipour <majidvp@chromium.org>
Date: Sun, 1 Apr 2018 16:03:14 -0400
Subject: [PATCH 07/11] minor cleanup

---
 lib/ui/dart_ui.cc        | 1 -
 lib/ui/painting/image.cc | 4 ++--
 lib/ui/painting/image.h  | 1 -
 3 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/lib/ui/dart_ui.cc b/lib/ui/dart_ui.cc
index 25b5bdf44a95d..59d083a191778 100644
--- a/lib/ui/dart_ui.cc
+++ b/lib/ui/dart_ui.cc
@@ -12,7 +12,6 @@
 #include "flutter/lib/ui/painting/frame_info.h"
 #include "flutter/lib/ui/painting/gradient.h"
 #include "flutter/lib/ui/painting/image.h"
-#include "flutter/lib/ui/painting/image_encoding.h"
 #include "flutter/lib/ui/painting/image_filter.h"
 #include "flutter/lib/ui/painting/image_shader.h"
 #include "flutter/lib/ui/painting/path.h"
diff --git a/lib/ui/painting/image.cc b/lib/ui/painting/image.cc
index db8a227bb44c5..42e733241c990 100644
--- a/lib/ui/painting/image.cc
+++ b/lib/ui/painting/image.cc
@@ -40,8 +40,8 @@ CanvasImage::~CanvasImage() {
 
 Dart_Handle CanvasImage::toByteData(int format,
                                     int quality,
-                                    Dart_Handle callback_handle) {
-  return EncodeImage(this, format, quality, callback_handle);
+                                    Dart_Handle callback) {
+  return EncodeImage(this, format, quality, callback);
 }
 
 void CanvasImage::dispose() {
diff --git a/lib/ui/painting/image.h b/lib/ui/painting/image.h
index 69d63cca51b84..a7ed4298506f5 100644
--- a/lib/ui/painting/image.h
+++ b/lib/ui/painting/image.h
@@ -28,7 +28,6 @@ class CanvasImage final : public fxl::RefCountedThreadSafe<CanvasImage>,
   int width() { return image_->width(); }
   int height() { return image_->height(); }
   Dart_Handle toByteData(int format, int quality, Dart_Handle callback);
-
   void dispose();
 
   const sk_sp<SkImage>& image() const { return image_; }

From e8a88202fc3d4cc687450bb7fb4afc792616747d Mon Sep 17 00:00:00 2001
From: Majid Valipour <majidvp@chromium.org>
Date: Wed, 4 Apr 2018 22:38:19 -0400
Subject: [PATCH 08/11] Make EncodingFormat a class

---
 lib/ui/painting.dart                          |  88 +++++++++++++++---
 testing/dart/encoding_test.dart               |  52 +++++------
 .../resources/{square-80.png => square.png}   | Bin
 3 files changed, 100 insertions(+), 40 deletions(-)
 rename testing/resources/{square-80.png => square.png} (100%)

diff --git a/lib/ui/painting.dart b/lib/ui/painting.dart
index be6e12dcac481..56b49617c50b4 100644
--- a/lib/ui/painting.dart
+++ b/lib/ui/painting.dart
@@ -1196,14 +1196,78 @@ class Paint {
   }
 }
 
-/// The encoding formats supported by the [Image.toByteData].
-// These enum values must be kept in sync with the logic in ToSkEncodedImageFormat.
-enum EncodeFormat {
-  // Be conservative with the formats we expose. It is easy to add new formats in future but
-  // difficult to remove.
-  JPEG,
-  PNG,
-  WEBP,
+/// An encoding format to use with the [Image.toByteData].
+class EncodingFormat {
+  final int _format;
+  final int _quality;
+
+  // Be conservative with the formats we expose. It is easy to add new formats
+  // in future but difficult to remove.
+  // These values must be kept in sync with the logic in ToSkEncodedImageFormat.
+  static const int _jpegFormat = 0;
+  static const int _pngFormat = 1;
+  static const int _webpFormat = 2;
+
+  /// PNG format.
+  ///
+  /// A loss-less compression format for images. This format is well suited for
+  /// images with hard edges, such as screenshots or sprites, and images with
+  /// text. Transparency is supported. The PNG format supports images up to
+  /// 2,147,483,647 pixels in either dimension, though in practice available
+  /// memory provides a more immediate limitation on maximum image size.
+  ///
+  /// PNG images normally use the `.png` file extension and the `image/png` MIME
+  /// type.
+  ///
+  /// See also:
+  ///
+  ///  * <https://en.wikipedia.org/wiki/Portable_Network_Graphics>, the Wikipedia page on PNG.
+  ///  * <https://tools.ietf.org/rfc/rfc2083.txt>, the PNG standard.
+  const EncodingFormat.png()
+      : _format = _pngFormat,
+        _quality = 0;
+
+  /// JPEG format.
+  ///
+  /// This format, strictly speaking called JFIF, is a lossy compression
+  /// graphics format that can handle images up to 65,535 pixels in either
+  /// dimension. The [quality] metric is a value in the range 0 to 100 that
+  /// controls the compression ratio. Values in the range of about 50 to 90 are
+  /// somewhat reasonable; values above 95 increase the file size with little
+  /// noticeable improvement to the quality, values below 50 drop the quality
+  /// substantially.
+  ///
+  /// This format is well suited for photographs. It is very poorly suited for
+  /// images with hard edges or text. It does not support transparency.
+  ///
+  /// JPEG images normally use the `.jpeg` file extension and the `image/jpeg`
+  /// MIME type.
+  ///
+  /// See also:
+  ///
+  ///  * <https://en.wikipedia.org/wiki/JPEG>, the Wikipedia page on JPEG.
+  const EncodingFormat.jpeg({int quality = 80})
+      : _format = _jpegFormat,
+        _quality = quality;
+
+  /// WebP format.
+  ///
+  /// The WebP format supports both lossy and lossless compression; however, the
+  /// [Image.toByteData] method always uses lossy compression when [webp] is
+  /// specified. The [quality] metric is a value in the range 0 to 100 that
+  /// controls the compression ratio; higher values result in better quality but
+  /// larger file sizes, and vice versa. WebP images are limited to 16,383
+  /// pixels in each direction (width and height).
+  ///
+  /// WebP images normally use the `.webp` file extension and the `image/webp`
+  /// MIME type.
+  ///
+  /// See also:
+  ///
+  ///  * <https://en.wikipedia.org/wiki/WebP>, the Wikipedia page on WebP.
+  const EncodingFormat.webp({int quality = 80})
+      : _format = _webpFormat,
+        _quality = quality;
 }
 
 /// Opaque handle to raw decoded image data (pixels).
@@ -1229,15 +1293,11 @@ class Image extends NativeFieldWrapperClass2 {
   ///
   /// The [format] is encoding format to be used.
   ///
-  /// The [quality] is a value in the range 0 to 100. [quality] is a format specific metric trading
-  /// off size and encoding error. When used, 100 encodes with highest quality (i.e., least error)
-  /// and 0 encodes with lowest quality (i.e., smallest size).
-  ///
   /// Returns a future which complete with the binary image data (e.g a PNG or JPEG binary data) or
   /// an error if encoding fails.
-  Future<Uint8List> toByteData({EncodeFormat format: EncodeFormat.JPEG, int quality: 80}) {
+  Future<Uint8List> toByteData({EncodingFormat format: const EncodingFormat.jpeg()}) {
     return _futurize(
-          (_Callback<Uint8List> callback) => _toByteData(format.index, quality, callback)
+          (_Callback<Uint8List> callback) => _toByteData(format._format, format._quality, callback)
     );
   }
 
diff --git a/testing/dart/encoding_test.dart b/testing/dart/encoding_test.dart
index 9848358154bf5..23c849aa64db3 100644
--- a/testing/dart/encoding_test.dart
+++ b/testing/dart/encoding_test.dart
@@ -12,27 +12,6 @@ import 'package:path/path.dart' as path;
 
 void main() {
 
-  Image createSquareTestImage() {
-    PictureRecorder recorder = new PictureRecorder();
-    Canvas canvas = new Canvas(recorder, new Rect.fromLTWH(0.0, 0.0, 10.0, 10.0));
-
-    var black = new Paint()
-      ..strokeWidth = 1.0
-      ..color = const Color.fromRGBO(0, 0, 0, 1.0);
-    var green = new Paint()
-      ..strokeWidth = 1.0
-      ..color = const Color.fromRGBO(0, 255, 0, 1.0);
-
-    canvas.drawRect(new Rect.fromLTWH(0.0, 0.0, 10.0, 10.0), black);
-    canvas.drawRect(new Rect.fromLTWH(2.0, 2.0, 6.0, 6.0), green);
-    return recorder.endRecording().toImage(10, 10);
-  }
-
-  Uint8List readFile(fileName) {
-    final file = new File(path.join('flutter', 'testing', 'resources', fileName));
-    return file.readAsBytesSync();
-  }
-
   final Image testImage = createSquareTestImage();
 
   test('Encode with default arguments', () async {
@@ -42,20 +21,41 @@ void main() {
   });
 
   test('Encode JPEG', () async {
-    Uint8List data = await testImage.toByteData(format: EncodeFormat.JPEG, quality:80);
+    Uint8List data = await testImage.toByteData(format: new EncodingFormat.jpeg(quality:80));
     Uint8List expected = readFile('square-80.jpg');
     expect(data, expected);
   });
 
   test('Encode PNG', () async {
-    Uint8List data = await testImage.toByteData(format: EncodeFormat.PNG, quality: 80);
-    Uint8List expected = readFile('square-80.png');
+    Uint8List data = await testImage.toByteData(format: new EncodingFormat.png());
+    Uint8List expected = readFile('square.png');
     expect(data, expected);
   });
 
   test('Encode WEBP', () async {
-    Uint8List data = await testImage.toByteData(format: EncodeFormat.WEBP, quality: 80);
+    Uint8List data = await testImage.toByteData(format: new EncodingFormat.webp(quality: 80));
     Uint8List expected = readFile('square-80.webp');
     expect(data, expected);
   });
-}
\ No newline at end of file
+}
+
+Image createSquareTestImage() {
+  PictureRecorder recorder = new PictureRecorder();
+  Canvas canvas = new Canvas(recorder, new Rect.fromLTWH(0.0, 0.0, 10.0, 10.0));
+
+  Paint black = new Paint()
+    ..strokeWidth = 1.0
+    ..color = const Color.fromRGBO(0, 0, 0, 1.0);
+  Paint green = new Paint()
+    ..strokeWidth = 1.0
+    ..color = const Color.fromRGBO(0, 255, 0, 1.0);
+
+  canvas.drawRect(new Rect.fromLTWH(0.0, 0.0, 10.0, 10.0), black);
+  canvas.drawRect(new Rect.fromLTWH(2.0, 2.0, 6.0, 6.0), green);
+  return recorder.endRecording().toImage(10, 10);
+}
+
+Uint8List readFile(fileName) {
+  final file = new File(path.join('flutter', 'testing', 'resources', fileName));
+  return file.readAsBytesSync();
+}
diff --git a/testing/resources/square-80.png b/testing/resources/square.png
similarity index 100%
rename from testing/resources/square-80.png
rename to testing/resources/square.png

From 813e9eca87ab258c793e2a908c3d1a0f18ba08b5 Mon Sep 17 00:00:00 2001
From: Majid Valipour <majidvp@chromium.org>
Date: Wed, 4 Apr 2018 22:57:22 -0400
Subject: [PATCH 09/11] fix formatting of encoding_test.dart

---
 testing/dart/encoding_test.dart | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/testing/dart/encoding_test.dart b/testing/dart/encoding_test.dart
index 23c849aa64db3..853cebf05a79a 100644
--- a/testing/dart/encoding_test.dart
+++ b/testing/dart/encoding_test.dart
@@ -11,7 +11,6 @@ import 'package:test/test.dart';
 import 'package:path/path.dart' as path;
 
 void main() {
-
   final Image testImage = createSquareTestImage();
 
   test('Encode with default arguments', () async {
@@ -21,19 +20,22 @@ void main() {
   });
 
   test('Encode JPEG', () async {
-    Uint8List data = await testImage.toByteData(format: new EncodingFormat.jpeg(quality:80));
+    Uint8List data = await testImage.toByteData(
+        format: new EncodingFormat.jpeg(quality: 80));
     Uint8List expected = readFile('square-80.jpg');
     expect(data, expected);
   });
 
   test('Encode PNG', () async {
-    Uint8List data = await testImage.toByteData(format: new EncodingFormat.png());
+    Uint8List data =
+        await testImage.toByteData(format: new EncodingFormat.png());
     Uint8List expected = readFile('square.png');
     expect(data, expected);
   });
 
   test('Encode WEBP', () async {
-    Uint8List data = await testImage.toByteData(format: new EncodingFormat.webp(quality: 80));
+    Uint8List data = await testImage.toByteData(
+        format: new EncodingFormat.webp(quality: 80));
     Uint8List expected = readFile('square-80.webp');
     expect(data, expected);
   });

From cd5f265e89ac9aac3e7adb500742bfdcc15c460c Mon Sep 17 00:00:00 2001
From: Majid Valipour <majidvp@chromium.org>
Date: Thu, 5 Apr 2018 08:31:44 -0400
Subject: [PATCH 10/11] Switch to returning ByteData

---
 lib/ui/painting.dart            | 11 +++++++----
 testing/dart/encoding_test.dart | 26 +++++++++++++-------------
 2 files changed, 20 insertions(+), 17 deletions(-)

diff --git a/lib/ui/painting.dart b/lib/ui/painting.dart
index 56b49617c50b4..7de1e8719c318 100644
--- a/lib/ui/painting.dart
+++ b/lib/ui/painting.dart
@@ -1295,10 +1295,13 @@ class Image extends NativeFieldWrapperClass2 {
   ///
   /// Returns a future which complete with the binary image data (e.g a PNG or JPEG binary data) or
   /// an error if encoding fails.
-  Future<Uint8List> toByteData({EncodingFormat format: const EncodingFormat.jpeg()}) {
-    return _futurize(
-          (_Callback<Uint8List> callback) => _toByteData(format._format, format._quality, callback)
-    );
+  Future<ByteData> toByteData({EncodingFormat format: const EncodingFormat.jpeg()}) {
+    return _futurize((_Callback<ByteData> callback) {
+      _toByteData(format._format, format._quality, (Uint8List encoded) {
+        callback(new ByteData.view(encoded.buffer));
+      });
+    });
+
   }
 
   /// Returns an error message on failure, null on success.
diff --git a/testing/dart/encoding_test.dart b/testing/dart/encoding_test.dart
index 853cebf05a79a..5fbbb4eb63909 100644
--- a/testing/dart/encoding_test.dart
+++ b/testing/dart/encoding_test.dart
@@ -14,30 +14,30 @@ void main() {
   final Image testImage = createSquareTestImage();
 
   test('Encode with default arguments', () async {
-    Uint8List data = await testImage.toByteData();
-    Uint8List expected = readFile('square-80.jpg');
-    expect(data, expected);
+    ByteData data = await testImage.toByteData();
+    List<int> expected = readFile('square-80.jpg');
+    expect(new Uint8List.view(data.buffer), expected);
   });
 
   test('Encode JPEG', () async {
-    Uint8List data = await testImage.toByteData(
+    ByteData data = await testImage.toByteData(
         format: new EncodingFormat.jpeg(quality: 80));
-    Uint8List expected = readFile('square-80.jpg');
-    expect(data, expected);
+    List<int> expected = readFile('square-80.jpg');
+    expect(new Uint8List.view(data.buffer), expected);
   });
 
   test('Encode PNG', () async {
-    Uint8List data =
+    ByteData data =
         await testImage.toByteData(format: new EncodingFormat.png());
-    Uint8List expected = readFile('square.png');
-    expect(data, expected);
+    List<int> expected = readFile('square.png');
+    expect(new Uint8List.view(data.buffer), expected);
   });
 
   test('Encode WEBP', () async {
-    Uint8List data = await testImage.toByteData(
+    ByteData data = await testImage.toByteData(
         format: new EncodingFormat.webp(quality: 80));
-    Uint8List expected = readFile('square-80.webp');
-    expect(data, expected);
+    List<int> expected = readFile('square-80.webp');
+    expect(new Uint8List.view(data.buffer), expected);
   });
 }
 
@@ -57,7 +57,7 @@ Image createSquareTestImage() {
   return recorder.endRecording().toImage(10, 10);
 }
 
-Uint8List readFile(fileName) {
+List<int> readFile(fileName) {
   final file = new File(path.join('flutter', 'testing', 'resources', fileName));
   return file.readAsBytesSync();
 }

From c89adb9841ffdc367356d616332fccf2408998fe Mon Sep 17 00:00:00 2001
From: Majid Valipour <majidvp@chromium.org>
Date: Thu, 5 Apr 2018 20:06:24 -0400
Subject: [PATCH 11/11] Address feedback

---
 lib/ui/painting.dart | 25 ++++++++++++-------------
 1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/lib/ui/painting.dart b/lib/ui/painting.dart
index 7de1e8719c318..4a874200f7eeb 100644
--- a/lib/ui/painting.dart
+++ b/lib/ui/painting.dart
@@ -1198,16 +1198,6 @@ class Paint {
 
 /// An encoding format to use with the [Image.toByteData].
 class EncodingFormat {
-  final int _format;
-  final int _quality;
-
-  // Be conservative with the formats we expose. It is easy to add new formats
-  // in future but difficult to remove.
-  // These values must be kept in sync with the logic in ToSkEncodedImageFormat.
-  static const int _jpegFormat = 0;
-  static const int _pngFormat = 1;
-  static const int _webpFormat = 2;
-
   /// PNG format.
   ///
   /// A loss-less compression format for images. This format is well suited for
@@ -1268,6 +1258,16 @@ class EncodingFormat {
   const EncodingFormat.webp({int quality = 80})
       : _format = _webpFormat,
         _quality = quality;
+
+  final int _format;
+  final int _quality;
+
+  // Be conservative with the formats we expose. It is easy to add new formats
+  // in future but difficult to remove.
+  // These values must be kept in sync with the logic in ToSkEncodedImageFormat.
+  static const int _jpegFormat = 0;
+  static const int _pngFormat = 1;
+  static const int _webpFormat = 2;
 }
 
 /// Opaque handle to raw decoded image data (pixels).
@@ -1297,11 +1297,10 @@ class Image extends NativeFieldWrapperClass2 {
   /// an error if encoding fails.
   Future<ByteData> toByteData({EncodingFormat format: const EncodingFormat.jpeg()}) {
     return _futurize((_Callback<ByteData> callback) {
-      _toByteData(format._format, format._quality, (Uint8List encoded) {
-        callback(new ByteData.view(encoded.buffer));
+      return _toByteData(format._format, format._quality, (Uint8List encoded) {
+        callback(encoded.buffer.asByteData());
       });
     });
-
   }
 
   /// Returns an error message on failure, null on success.