[WebRTC] Add ScreenCapturerDifferWrapper to share Differ across ScreenCapturers

webrtc/modules/desktop_capture/screen_capturer_differ_wrapper_unittest.cc

Index: webrtc/modules/desktop_capture/screen_capturer_differ_wrapper_unittest.cc
diff --git a/webrtc/modules/desktop_capture/screen_capturer_differ_wrapper_unittest.cc b/webrtc/modules/desktop_capture/screen_capturer_differ_wrapper_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..808f9863d5cd608c8d0571bdd656219efd7b2ee7
--- /dev/null
+++ b/webrtc/modules/desktop_capture/screen_capturer_differ_wrapper_unittest.cc
@@ -0,0 +1,282 @@
+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/modules/desktop_capture/screen_capturer_differ_wrapper.h"
+
+#include <initializer_list>
+#include <memory>
+#include <utility>
+#include <vector>
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "webrtc/base/random.h"
+#include "webrtc/base/timeutils.h"
+#include "webrtc/modules/desktop_capture/desktop_geometry.h"
+#include "webrtc/modules/desktop_capture/desktop_region.h"
+#include "webrtc/modules/desktop_capture/differ_block.h"
+#include "webrtc/modules/desktop_capture/fake_screen_capturer.h"
+#include "webrtc/modules/desktop_capture/screen_capturer_mock_objects.h"
+#include "webrtc/system_wrappers/include/cpu_features_wrapper.h"
+#include "webrtc/typedefs.h"
+
+namespace webrtc {
+
+namespace {
+
+// ScreenCapturerDifferWrapper always use a 32 x 32 pixel block. So we normalize
+// the |rects|.
+DesktopRect NormalizeDesktopRect(DesktopRect rect, DesktopSize size) {
+  DesktopRect block_size_rect = DesktopRect::MakeLTRB(
+      rect.left() / kBlockSize * kBlockSize,
+      rect.top() / kBlockSize * kBlockSize,
+      (rect.right() + kBlockSize - 1) / kBlockSize * kBlockSize,
+      (rect.bottom() + kBlockSize - 1) / kBlockSize * kBlockSize);
+  block_size_rect.IntersectWith(DesktopRect::MakeSize(size));
+  return block_size_rect;
+}
+
+// Compares and asserts |frame|.updated_region() equals to |rects|. This
+// function does not care about the order of the |rects|.
+template <template <typename, typename...> class T = std::initializer_list,
+          typename... Rect>
+void AssertUpdatedRegionIs(const DesktopFrame& frame,
+                           const T<DesktopRect, Rect...>& rects) {
+  for (const DesktopRect& rect : rects) {
+    DesktopRect block_size_rect = NormalizeDesktopRect(rect, frame.size());
+    bool found = false;
+    for (DesktopRegion::Iterator it(frame.updated_region()); !it.IsAtEnd();
+         it.Advance()) {
+      if (it.rect().equals(block_size_rect)) {
+        found = true;
+        break;
+      }
+    }
+
+    ASSERT_TRUE(found);
+  }
+}
+
+// Compares and asserts |frame|.updated_region() covers all rectangles in
+// |rects|, but does not cover areas other than a kBlockSize expansion. This
+// function does not care about the order of the |rects|, and it does not expect
+// DesktopRegion to return an exact area of each rectangle in |rects|.
+template <template <typename, typename...> class T = std::initializer_list,
+          typename... Rect>
+void AssertUpdatedRegionCovers(const DesktopFrame& frame,
+                               const T<DesktopRect, Rect...>& rects) {
+  DesktopRegion region;
+  for (const auto& rect : rects) {
+    region.AddRect(NormalizeDesktopRect(rect, frame.size()));
+  }
+  ASSERT_TRUE(frame.updated_region().Equals(region));
+}
+
+// Executes a ScreenCapturerDifferWrapper::Capture() and compares its output
+// DesktopFrame::updated_region() with |updated_region| if |check_result| is
+// true. If |exactly_match| is true, AssertUpdatedRegionIs() will be used,
+// otherwise AssertUpdatedRegionCovers() will be used.
+template <template <typename, typename...> class T = std::initializer_list,
+          typename... Rect>
+void ExecuteDifferWrapperCase(BlackWhiteDesktopFrameGenerator* frame_generator,
+                              ScreenCapturerDifferWrapper* capturer,
+                              MockScreenCapturerCallback* callback,
+                              const T<DesktopRect, Rect...>& updated_region,
+                              bool check_result,
+                              bool exactly_match) {
+  EXPECT_CALL(*callback,
+              OnCaptureResultPtr(DesktopCapturer::Result::SUCCESS, testing::_))
+      .Times(1)
+      .WillOnce(testing::Invoke([&updated_region, check_result, exactly_match](
+          DesktopCapturer::Result result,
+          std::unique_ptr<DesktopFrame>* frame) {
+        ASSERT_EQ(result, DesktopCapturer::Result::SUCCESS);
+        if (check_result) {
+          if (exactly_match) {
+            AssertUpdatedRegionIs(**frame, updated_region);
+          } else {
+            AssertUpdatedRegionCovers(**frame, updated_region);
+          }
+        }
+      }));
+  for (const auto& rect : updated_region) {
+    frame_generator->updated_region()->AddRect(rect);
+  }
+  capturer->Capture(DesktopRegion());
+}
+
+// Executes a ScreenCapturerDifferWrapper::Capture(), if updated_region() is not
+// set, this function will reset ScreenCapturerDifferWrapper internal
+// DesktopFrame into white.
+void ExecuteCapturer(ScreenCapturerDifferWrapper* capturer,
+                     MockScreenCapturerCallback* callback) {
+  EXPECT_CALL(*callback,
+              OnCaptureResultPtr(DesktopCapturer::Result::SUCCESS, testing::_))
+      .Times(1);
+  capturer->Capture(DesktopRegion());
+}
+
+void ExecuteDifferWrapperTest(bool with_hints,
+                              bool enlarge_updated_region,
+                              bool random_updated_region,
+                              bool check_result) {
+  BlackWhiteDesktopFrameGenerator frame_generator;
+  std::unique_ptr<FakeScreenCapturer> fake(new FakeScreenCapturer());
+  fake->set_frame_generator(&frame_generator);
+  ScreenCapturerDifferWrapper capturer(std::move(fake), !with_hints);
+  MockScreenCapturerCallback callback;
+  frame_generator.set_provide_updated_region_hints(with_hints);
+  frame_generator.set_enlarge_updated_region(enlarge_updated_region);
+  frame_generator.set_add_random_updated_region(random_updated_region);
+
+  capturer.Start(&callback);
+
+  EXPECT_CALL(callback,
+              OnCaptureResultPtr(DesktopCapturer::Result::SUCCESS, testing::_))
+      .Times(1)
+      .WillOnce(testing::Invoke([](DesktopCapturer::Result result,
+                                   std::unique_ptr<DesktopFrame>* frame) {
+        ASSERT_EQ(result, DesktopCapturer::Result::SUCCESS);
+        AssertUpdatedRegionIs(**frame,
+                              {DesktopRect::MakeSize((*frame)->size())});
+      }));
+  capturer.Capture(DesktopRegion());
+
+  ExecuteDifferWrapperCase(&frame_generator, &capturer, &callback,
+                           {DesktopRect::MakeLTRB(100, 100, 200, 200),
+                            DesktopRect::MakeLTRB(300, 300, 400, 400)},
+                           check_result, true);
+  ExecuteCapturer(&capturer, &callback);
+
+  ExecuteDifferWrapperCase(
+      &frame_generator, &capturer, &callback,
+      {DesktopRect::MakeLTRB(0, 0, 40, 40),
+       DesktopRect::MakeLTRB(0, frame_generator.size()->height() - 40, 40,
+                             frame_generator.size()->height()),
+       DesktopRect::MakeLTRB(frame_generator.size()->width() - 40, 0,
+                             frame_generator.size()->width(), 40),
+       DesktopRect::MakeLTRB(frame_generator.size()->width() - 40,
+                             frame_generator.size()->height() - 40,
+                             frame_generator.size()->width(),
+                             frame_generator.size()->height())},
+      check_result, true);
+
+  Random random(rtc::TimeMillis());
+  // Fuzzing tests.
+  for (int i = 0; i < 1000; i++) {
+    if (enlarge_updated_region) {
+      frame_generator.set_enlarge_range(random.Rand(1, 50));
+    }
+    frame_generator.size()->set(random.Rand(500, 2000), random.Rand(500, 2000));
+    ExecuteCapturer(&capturer, &callback);
+    std::vector<DesktopRect> updated_region;
+    for (int j = random.Rand(50); j >= 0; j--) {
+      // At least a 1 x 1 updated region.
+      const int left = random.Rand(0, frame_generator.size()->width() - 2);
+      const int top = random.Rand(0, frame_generator.size()->height() - 2);
+      const int right = random.Rand(left + 1, frame_generator.size()->width());
+      const int bottom = random.Rand(top + 1, frame_generator.size()->height());
+      updated_region.push_back(DesktopRect::MakeLTRB(left, top, right, bottom));
+    }
+    ExecuteDifferWrapperCase(&frame_generator, &capturer, &callback,
+                             updated_region, check_result, false);
+  }
+}
+
+}  // namespace
+
+TEST(ScreenCapturerDifferWrapperTest, CaptureWithoutHints) {
+  ExecuteDifferWrapperTest(false, false, false, true);
+}
+
+TEST(ScreenCapturerDifferWrapperTest, CaptureWithHints) {
+  ExecuteDifferWrapperTest(true, false, false, true);
+}
+
+TEST(ScreenCapturerDifferWrapperTest, CaptureWithEnlargedHints) {
+  ExecuteDifferWrapperTest(true, true, false, true);
+}
+
+TEST(ScreenCapturerDifferWrapperTest, CaptureWithRandomHints) {
+  ExecuteDifferWrapperTest(true, false, true, true);
+}
+
+TEST(ScreenCapturerDifferWrapperTest, CaptureWithEnlargedAndRandomHints) {
+  ExecuteDifferWrapperTest(true, true, true, true);
+}
+
+// SSE2 is not available on ARM / MIPS, so the performance should be extremely
+// lower.
+#if defined(WEBRTC_ARCH_X86_FAMILY)
+// When hints are enabled, ScreenCapturerDifferWrapper has a slightly better
+// performance in current configuration, but not so significant. Following is
+// one run result.
+// [ RUN      ] DISABLED_CaptureWithoutHintsPerf
+// [       OK ] DISABLED_CaptureWithoutHintsPerf (8889 ms)
+// [ RUN      ] DISABLED_CaptureWithHintsPerf
+// [       OK ] DISABLED_CaptureWithHintsPerf (7814 ms)
+// [ RUN      ] DISABLED_CaptureWithEnlargedHintsPerf
+// [       OK ] DISABLED_CaptureWithEnlargedHintsPerf (7999 ms)
+// [ RUN      ] DISABLED_CaptureWithRandomHintsPerf
+// [       OK ] DISABLED_CaptureWithRandomHintsPerf (8429 ms)
+// [ RUN      ] DISABLED_CaptureWithEnlargedAndRandomHintsPerf
+// [       OK ] DISABLED_CaptureWithEnlargedAndRandomHintsPerf (8552 ms)
+TEST(ScreenCapturerDifferWrapperTest, DISABLED_CaptureWithoutHintsPerf) {
+  if (WebRtc_GetCPUInfo(kSSE2) == 0) {
+    return;
+  }
+
+  int64_t started = rtc::TimeMillis();
+  ExecuteDifferWrapperTest(false, false, false, false);
+  ASSERT_LE(rtc::TimeMillis() - started, 15000);
+}
+
+TEST(ScreenCapturerDifferWrapperTest, DISABLED_CaptureWithHintsPerf) {
+  if (WebRtc_GetCPUInfo(kSSE2) == 0) {
+    return;
+  }
+
+  int64_t started = rtc::TimeMillis();
+  ExecuteDifferWrapperTest(true, false, false, false);
+  ASSERT_LE(rtc::TimeMillis() - started, 15000);
+}
+
+TEST(ScreenCapturerDifferWrapperTest, DISABLED_CaptureWithEnlargedHintsPerf) {
+  if (WebRtc_GetCPUInfo(kSSE2) == 0) {
+    return;
+  }
+
+  int64_t started = rtc::TimeMillis();
+  ExecuteDifferWrapperTest(true, true, false, false);
+  ASSERT_LE(rtc::TimeMillis() - started, 15000);
+}
+
+TEST(ScreenCapturerDifferWrapperTest, DISABLED_CaptureWithRandomHintsPerf) {
+  if (WebRtc_GetCPUInfo(kSSE2) == 0) {
+    return;
+  }
+
+  int64_t started = rtc::TimeMillis();
+  ExecuteDifferWrapperTest(true, false, true, false);
+  ASSERT_LE(rtc::TimeMillis() - started, 15000);
+}
+
+TEST(ScreenCapturerDifferWrapperTest,
+     DISABLED_CaptureWithEnlargedAndRandomHintsPerf) {
+  if (WebRtc_GetCPUInfo(kSSE2) == 0) {
+    return;
+  }
+
+  int64_t started = rtc::TimeMillis();
+  ExecuteDifferWrapperTest(true, true, true, false);
+  ASSERT_LE(rtc::TimeMillis() - started, 15000);
+}
+#endif
+
+}  // namespace webrtc