Use webrtc::DesktopCapturer for screen capturer implementation.

media/video/capture/screen/screen_capturer_win.cc

 // Copyright (c) 2012 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 "media/video/capture/screen/screen_capturer.h"
 
 #include <windows.h>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/scoped_native_library.h"
 #include "base/stl_util.h"
 #include "base/time.h"
 #include "base/utf_string_conversions.h"
 #include "base/win/scoped_gdi_object.h"
 #include "base/win/scoped_hdc.h"
 #include "media/video/capture/screen/differ.h"
 #include "media/video/capture/screen/mouse_cursor_shape.h"
-#include "media/video/capture/screen/screen_capture_data.h"
-#include "media/video/capture/screen/screen_capture_frame.h"
 #include "media/video/capture/screen/screen_capture_frame_queue.h"
 #include "media/video/capture/screen/screen_capturer_helper.h"
 #include "media/video/capture/screen/win/desktop.h"
 #include "media/video/capture/screen/win/scoped_thread_desktop.h"
 #include "third_party/skia/include/core/SkColorPriv.h"
+#include "third_party/webrtc/modules/desktop_capture/desktop_frame.h"
+#include "third_party/webrtc/modules/desktop_capture/desktop_frame_win.h"
+#include "third_party/webrtc/modules/desktop_capture/desktop_region.h"
 
 namespace media {
 
 namespace {
 
 // Constants from dwmapi.h.
 const UINT DWM_EC_DISABLECOMPOSITION = 0;
 const UINT DWM_EC_ENABLECOMPOSITION = 1;
 
 typedef HRESULT (WINAPI * DwmEnableCompositionFunc)(UINT);
 
 const char kDwmapiLibraryName[] = "dwmapi";
 
 // Pixel colors used when generating cursor outlines.
 const uint32 kPixelBgraBlack = 0xff000000;
 const uint32 kPixelBgraWhite = 0xffffffff;
 const uint32 kPixelBgraTransparent = 0x00000000;
 
-// A class representing a full-frame pixel buffer.
-class ScreenCaptureFrameWin : public ScreenCaptureFrame {
- public:
-  ScreenCaptureFrameWin(HDC desktop_dc, const SkISize& size,
-                        ScreenCapturer::Delegate* delegate);
-  virtual ~ScreenCaptureFrameWin();
-
-  // Returns handle of the device independent bitmap representing this frame
-  // buffer to GDI.
-  HBITMAP GetBitmap();
-
- private:
-  // Allocates a device independent bitmap representing this frame buffer to
-  // GDI.
-  void AllocateBitmap(HDC desktop_dc, const SkISize& size);
-
-  // Handle of the device independent bitmap representing this frame buffer to
-  // GDI.
-  base::win::ScopedBitmap bitmap_;
-
-  // Used to work with shared memory buffers.
-  ScreenCapturer::Delegate* delegate_;
-
-  DISALLOW_COPY_AND_ASSIGN(ScreenCaptureFrameWin);
-};
-
 // ScreenCapturerWin captures 32bit RGB using GDI.
 //
 // ScreenCapturerWin is double-buffered as required by ScreenCapturer.
 class ScreenCapturerWin : public ScreenCapturer {
  public:
   ScreenCapturerWin(bool disable_aero);
   virtual ~ScreenCapturerWin();
 
   // Overridden from ScreenCapturer:
-  virtual void Start(Delegate* delegate) OVERRIDE;
-  virtual void CaptureFrame() OVERRIDE;
+  virtual void Start(Callback* callback) OVERRIDE;
+  virtual void Capture(const webrtc::DesktopRegion& region) OVERRIDE;
+  virtual void SetMouseShapeObserver(
+      MouseShapeObserver* mouse_shape_observer) OVERRIDE;
 
  private:
   // Make sure that the device contexts match the screen configuration.
   void PrepareCaptureResources();
 
-  // Creates a ScreenCaptureData instance wrapping the current framebuffer and
-  // notifies |delegate_|.
-  void CaptureRegion(const SkRegion& region,
+  // Creates a webrtc::DesktopFrame instance wrapping the current framebuffer
+  // and notifies |callback_|.
+  void CaptureRegion(const webrtc::DesktopRegion& region,
                      const base::Time& capture_start_time);
 
   // Captures the current screen contents into the current buffer.
   void CaptureImage();
 
   // Expand the cursor shape to add a white outline for visibility against
   // dark backgrounds.
   void AddCursorOutline(int width, int height, uint32* dst);
 
   // Capture the current cursor shape.
   void CaptureCursor();
 
-  Delegate* delegate_;
+  Callback* callback_;
+  MouseShapeObserver* mouse_shape_observer_;
 
   // A thread-safe list of invalid rectangles, and the size of the most
   // recently captured screen.
   ScreenCapturerHelper helper_;
 
   // Snapshot of the last cursor bitmap we sent to the client. This is used
   // to diff against the current cursor so we only send a cursor-change
   // message when the shape has changed.
   MouseCursorShape last_cursor_;
 
@@ skipping 14 matching lines @@
 
   base::ScopedNativeLibrary dwmapi_library_;
   DwmEnableCompositionFunc composition_func_;
 
   // Used to suppress duplicate logging of SetThreadExecutionState errors.
   bool set_thread_execution_state_failed_;
 
   DISALLOW_COPY_AND_ASSIGN(ScreenCapturerWin);
 };
 
-// 3780 pixels per meter is equivalent to 96 DPI, typical on desktop monitors.
-static const int kPixelsPerMeter = 3780;
-
-ScreenCaptureFrameWin::ScreenCaptureFrameWin(
-    HDC desktop_dc,
-    const SkISize& size,
-    ScreenCapturer::Delegate* delegate)
-    : delegate_(delegate) {
-  // Try to allocate a shared memory buffer.
-  uint32 buffer_size =
-    size.width() * size.height() * ScreenCaptureData::kBytesPerPixel;
-  scoped_refptr<SharedBuffer> shared_buffer =
-      delegate_->CreateSharedBuffer(buffer_size);
-  if (shared_buffer) {
-    CHECK(shared_buffer->ptr() != NULL);
-    set_shared_buffer(shared_buffer);
-  }
-
-  AllocateBitmap(desktop_dc, size);
-}
-
-ScreenCaptureFrameWin::~ScreenCaptureFrameWin() {
-  if (shared_buffer())
-    delegate_->ReleaseSharedBuffer(shared_buffer());
-}
-
-HBITMAP ScreenCaptureFrameWin::GetBitmap() {
-  return bitmap_;
-}
-
-void ScreenCaptureFrameWin::AllocateBitmap(HDC desktop_dc,
-                                           const SkISize& size) {
-  int bytes_per_row = size.width() * ScreenCaptureData::kBytesPerPixel;
-
-  // Describe a device independent bitmap (DIB) that is the size of the desktop.
-  BITMAPINFO bmi;
-  memset(&bmi, 0, sizeof(bmi));
-  bmi.bmiHeader.biHeight = -size.height();
-  bmi.bmiHeader.biWidth = size.width();
-  bmi.bmiHeader.biPlanes = 1;
-  bmi.bmiHeader.biBitCount = ScreenCaptureData::kBytesPerPixel * 8;
-  bmi.bmiHeader.biSize = sizeof(bmi.bmiHeader);
-  bmi.bmiHeader.biSizeImage = bytes_per_row * size.height();
-  bmi.bmiHeader.biXPelsPerMeter = kPixelsPerMeter;
-  bmi.bmiHeader.biYPelsPerMeter = kPixelsPerMeter;
-
-  // Create the DIB, and store a pointer to its pixel buffer.
-  HANDLE section_handle = NULL;
-  if (shared_buffer())
-    section_handle = shared_buffer()->handle();
-  void* data = NULL;
-  bitmap_ = CreateDIBSection(desktop_dc, &bmi, DIB_RGB_COLORS, &data,
-                             section_handle, 0);
-
-  // TODO(wez): Cope gracefully with failure (crbug.com/157170).
-  CHECK(bitmap_ != NULL);
-  CHECK(data != NULL);
-
-  set_pixels(reinterpret_cast<uint8*>(data));
-  set_dimensions(SkISize::Make(bmi.bmiHeader.biWidth,
-                               std::abs(bmi.bmiHeader.biHeight)));
-  set_bytes_per_row(
-      bmi.bmiHeader.biSizeImage / std::abs(bmi.bmiHeader.biHeight));
-}
-
 ScreenCapturerWin::ScreenCapturerWin(bool disable_aero)
-    : delegate_(NULL),
+    : callback_(NULL),
+      mouse_shape_observer_(NULL),
       desktop_dc_rect_(SkIRect::MakeEmpty()),
       composition_func_(NULL),
       set_thread_execution_state_failed_(false) {
   if (disable_aero) {
     // Load dwmapi.dll dynamically since it is not available on XP.
     if (!dwmapi_library_.is_valid()) {
       base::FilePath path(base::GetNativeLibraryName(
           UTF8ToUTF16(kDwmapiLibraryName)));
       dwmapi_library_.Reset(base::LoadNativeLibrary(path, NULL));
     }
 
     if (dwmapi_library_.is_valid() && composition_func_ == NULL) {
       composition_func_ = reinterpret_cast<DwmEnableCompositionFunc>(
           dwmapi_library_.GetFunctionPointer("DwmEnableComposition"));
     }
   }
 }
 
 ScreenCapturerWin::~ScreenCapturerWin() {
   // Restore Aero.
   if (composition_func_ != NULL) {
     (*composition_func_)(DWM_EC_ENABLECOMPOSITION);
   }
 
-  delegate_ = NULL;
+  callback_ = NULL;

[alexeypa (please no reviews), 2013/04/26 21:33:58]

nit: Remove this line.

[Sergey Ulanov, 2013/05/07 22:25:50]

Done.

 }
 
-void ScreenCapturerWin::CaptureFrame() {
+void ScreenCapturerWin::Capture(const webrtc::DesktopRegion& region) {
   base::Time capture_start_time = base::Time::Now();
 
   // Request that the system not power-down the system, or the display hardware.
   if (!SetThreadExecutionState(ES_DISPLAY_REQUIRED | ES_SYSTEM_REQUIRED)) {
     if (!set_thread_execution_state_failed_) {
       set_thread_execution_state_failed_ = true;
       LOG_GETLASTERROR(WARNING)
           << "Failed to make system & display power assertion";
     }
   }
 
   // Make sure the GDI capture resources are up-to-date.
   PrepareCaptureResources();
 
   // Copy screen bits to the current buffer.
   CaptureImage();
 
-  const ScreenCaptureFrame* current_buffer = queue_.current_frame();
-  const ScreenCaptureFrame* last_buffer = queue_.previous_frame();
+  const webrtc::DesktopFrame* current_buffer = queue_.current_frame();
+  const webrtc::DesktopFrame* last_buffer = queue_.previous_frame();
   if (last_buffer) {
     // Make sure the differencer is set up correctly for these previous and
     // current screens.
     if (!differ_.get() ||
-        (differ_->width() != current_buffer->dimensions().width()) ||
-        (differ_->height() != current_buffer->dimensions().height()) ||
-        (differ_->bytes_per_row() != current_buffer->bytes_per_row())) {
-      differ_.reset(new Differ(current_buffer->dimensions().width(),
-                               current_buffer->dimensions().height(),
-                               ScreenCaptureData::kBytesPerPixel,
-                               current_buffer->bytes_per_row()));
+        (differ_->width() != current_buffer->size().width()) ||
+        (differ_->height() != current_buffer->size().height()) ||
+        (differ_->bytes_per_row() != current_buffer->stride())) {
+      differ_.reset(new Differ(current_buffer->size().width(),
+                               current_buffer->size().height(),
+                               webrtc::DesktopFrame::kBytesPerPixel,
+                               current_buffer->stride()));
     }
 
     // Calculate difference between the two last captured frames.
-    SkRegion region;
-    differ_->CalcDirtyRegion(last_buffer->pixels(), current_buffer->pixels(),
+    webrtc::DesktopRegion region;
+    differ_->CalcDirtyRegion(last_buffer->data(), current_buffer->data(),
                              &region);
     helper_.InvalidateRegion(region);
   } else {
     // No previous frame is available. Invalidate the whole screen.
-    helper_.InvalidateScreen(current_buffer->dimensions());
+    helper_.InvalidateScreen(current_buffer->size());
   }
 
   // Wrap the captured frame into ScreenCaptureData structure and invoke
   // the completion callback.
-  SkRegion invalid_region;
+  webrtc::DesktopRegion invalid_region;
   helper_.SwapInvalidRegion(&invalid_region);
   CaptureRegion(invalid_region, capture_start_time);
 
   // Check for cursor shape update.
   CaptureCursor();
 }
 
-void ScreenCapturerWin::Start(Delegate* delegate) {
-  DCHECK(delegate_ == NULL);
+void ScreenCapturerWin::SetMouseShapeObserver(
+      MouseShapeObserver* mouse_shape_observer) {
+  mouse_shape_observer_ = mouse_shape_observer;

[alexeypa (please no reviews), 2013/04/26 21:33:58]

DCHECK(!mouse_shape_observer_);
DCHECK(mouse_shape_observer);

[Sergey Ulanov, 2013/05/07 22:25:50]

Done.

+}
 
-  delegate_ = delegate;
+void ScreenCapturerWin::Start(Callback* callback) {
+  DCHECK(callback_ == NULL);

[alexeypa (please no reviews), 2013/04/26 21:33:58]

DCHECK(!callback_);
DCHECK(callback);

[Sergey Ulanov, 2013/05/07 22:25:50]

Done.

+
+  callback_ = callback;
 
   // Vote to disable Aero composited desktop effects while capturing. Windows
   // will restore Aero automatically if the process exits. This has no effect
   // under Windows 8 or higher.  See crbug.com/124018.
   if (composition_func_ != NULL) {
     (*composition_func_)(DWM_EC_DISABLECOMPOSITION);
   }
 }
 
 void ScreenCapturerWin::PrepareCaptureResources() {
@@ skipping 37 matching lines @@
     memory_dc_.Set(CreateCompatibleDC(*desktop_dc_));
     desktop_dc_rect_ = screen_rect;
 
     // Make sure the frame buffers will be reallocated.
     queue_.SetAllFramesNeedUpdate();
 
     helper_.ClearInvalidRegion();
   }
 }
 
 void ScreenCapturerWin::CaptureRegion(

[Wez, 2013/04/26 18:48:14]

This needs renaming, e.g. EmitFrame().

[Sergey Ulanov, 2013/05/07 22:25:50]

Just removed this method.

-    const SkRegion& region,
+    const webrtc::DesktopRegion& region,
     const base::Time& capture_start_time) {
-  const ScreenCaptureFrame* current_buffer = queue_.current_frame();
+  webrtc::DesktopFrame* frame = queue_.EmitCurrentFrameAndMoveToNext();
+  frame->set_dpi(webrtc::DesktopVector(
+      GetDeviceCaps(*desktop_dc_, LOGPIXELSX),
+      GetDeviceCaps(*desktop_dc_, LOGPIXELSY)));
+  *frame->mutable_updated_region() = region;
+  frame->set_capture_time_ms(
+      (base::Time::Now() - capture_start_time).InMillisecondsRoundedUp());
 
-  scoped_refptr<ScreenCaptureData> data(new ScreenCaptureData(
-      current_buffer->pixels(), current_buffer->bytes_per_row(),
-      current_buffer->dimensions()));
-  data->mutable_dirty_region() = region;
-  data->set_shared_buffer(current_buffer->shared_buffer());
+  helper_.set_size_most_recent(frame->size());
 
-  SkIPoint dpi = SkIPoint::Make(
-      GetDeviceCaps(*desktop_dc_, LOGPIXELSX),
-      GetDeviceCaps(*desktop_dc_, LOGPIXELSY));
-  data->set_dpi(dpi);
-
-  helper_.set_size_most_recent(data->size());
-
-  queue_.DoneWithCurrentFrame();
-
-  data->set_capture_time_ms(
-      (base::Time::Now() - capture_start_time).InMillisecondsRoundedUp());
-  delegate_->OnCaptureCompleted(data);
+  callback_->OnCaptureCompleted(frame);
 }
 
 void ScreenCapturerWin::CaptureImage() {
   // If the current buffer is from an older generation then allocate a new one.
   // Note that we can't reallocate other buffers at this point, since the caller
   // may still be reading from them.
   if (queue_.current_frame_needs_update()) {
     DCHECK(desktop_dc_.get() != NULL);
     DCHECK(memory_dc_.Get() != NULL);
 
-    SkISize size = SkISize::Make(desktop_dc_rect_.width(),
-                                 desktop_dc_rect_.height());
-    scoped_ptr<ScreenCaptureFrameWin> buffer(
-        new ScreenCaptureFrameWin(*desktop_dc_, size, delegate_));
-    queue_.ReplaceCurrentFrame(buffer.PassAs<ScreenCaptureFrame>());
+    webrtc::DesktopSize size = webrtc::DesktopSize(
+        desktop_dc_rect_.width(), desktop_dc_rect_.height());
+
+    size_t buffer_size = size.width() * size.height() *
+        webrtc::DesktopFrame::kBytesPerPixel;
+    webrtc::SharedMemory* shared_memory =
+        callback_->CreateSharedMemory(buffer_size);
+    scoped_ptr<webrtc::DesktopFrameWin> buffer(
+        webrtc::DesktopFrameWin::Create(size, shared_memory, *desktop_dc_));
+    queue_.ReplaceCurrentFrame(buffer.PassAs<webrtc::DesktopFrame>());
   }
 
   // Select the target bitmap into the memory dc and copy the rect from desktop
   // to memory.
-  ScreenCaptureFrameWin* current = static_cast<ScreenCaptureFrameWin*>(
+  webrtc::DesktopFrameWin* current = static_cast<webrtc::DesktopFrameWin*>(
       queue_.current_frame());
-  HGDIOBJ previous_object = SelectObject(memory_dc_, current->GetBitmap());
+  HGDIOBJ previous_object = SelectObject(memory_dc_, current->bitmap());
   if (previous_object != NULL) {
     BitBlt(memory_dc_,
            0, 0, desktop_dc_rect_.width(), desktop_dc_rect_.height(),
            *desktop_dc_,
            desktop_dc_rect_.x(), desktop_dc_rect_.y(),
            SRCCOPY | CAPTUREBLT);
 
     // Select back the previously selected object to that the device contect
     // could be destroyed independently of the bitmap if needed.
     SelectObject(memory_dc_, previous_object);
@@ skipping 70 matching lines @@
   }
 
   int width = bitmap.bmWidth;
   int height = bitmap.bmHeight;
   // For non-color cursors, the mask contains both an AND and an XOR mask and
   // the height includes both. Thus, the width is correct, but we need to
   // divide by 2 to get the correct mask height.
   if (!color_bitmap) {
     height /= 2;
   }
-  int data_size = height * width * ScreenCaptureData::kBytesPerPixel;
+  int data_size = height * width * webrtc::DesktopFrame::kBytesPerPixel;
 
   scoped_ptr<MouseCursorShape> cursor(new MouseCursorShape());
   cursor->data.resize(data_size);
   uint8* cursor_dst_data =
       reinterpret_cast<uint8*>(string_as_array(&cursor->data));
 
   // Copy/convert cursor bitmap into format needed by chromotocol.
   int row_bytes = bitmap.bmWidthBytes;
   if (color_bitmap) {
     if (bitmap.bmPlanes != 1 || bitmap.bmBitsPixel != 32) {
       VLOG(3) << "Unsupported color cursor format. Error = " << GetLastError();
       return;
     }
 
     // Copy across colour cursor imagery.
     // MouseCursorShape stores imagery top-down, and premultiplied
     // by the alpha channel, whereas windows stores them bottom-up
     // and not premultiplied.
     uint8* cursor_src_data = reinterpret_cast<uint8*>(bitmap.bmBits);
     uint8* src = cursor_src_data + ((height - 1) * row_bytes);
     uint8* dst = cursor_dst_data;
     for (int row = 0; row < height; ++row) {
       for (int column = 0; column < width; ++column) {
         dst[0] = SkAlphaMul(src[0], src[3]);
         dst[1] = SkAlphaMul(src[1], src[3]);
         dst[2] = SkAlphaMul(src[2], src[3]);
         dst[3] = src[3];
-        dst += ScreenCaptureData::kBytesPerPixel;
-        src += ScreenCaptureData::kBytesPerPixel;
+        dst += webrtc::DesktopFrame::kBytesPerPixel;
+        src += webrtc::DesktopFrame::kBytesPerPixel;
       }
-      src -= row_bytes + (width * ScreenCaptureData::kBytesPerPixel);
+      src -= row_bytes + (width * webrtc::DesktopFrame::kBytesPerPixel);
     }
   } else {
     if (bitmap.bmPlanes != 1 || bitmap.bmBitsPixel != 1) {
       VLOG(3) << "Unsupported cursor mask format. Error = " << GetLastError();
       return;
     }
 
     // x2 because there are 2 masks in the bitmap: AND and XOR.
     int mask_bytes = height * row_bytes * 2;
     scoped_ptr<uint8[]> mask(new uint8[mask_bytes]);
@@ skipping 36 matching lines @@
       AddCursorOutline(width, height,
                        reinterpret_cast<uint32*>(cursor_dst_data));
     }
   }
 
   cursor->size.set(width, height);
   cursor->hotspot.set(hotspot_x, hotspot_y);
 
   // Compare the current cursor with the last one we sent to the client. If
   // they're the same, then don't bother sending the cursor again.
-  if (last_cursor_.size == cursor->size &&
-      last_cursor_.hotspot == cursor->hotspot &&
+  if (last_cursor_.size.equals(cursor->size) &&
+      last_cursor_.hotspot.equals(cursor->hotspot) &&
       last_cursor_.data == cursor->data) {
     return;
   }
 
   VLOG(3) << "Sending updated cursor: " << width << "x" << height;
 
   // Record the last cursor image that we sent to the client.
   last_cursor_ = *cursor;
 
-  delegate_->OnCursorShapeChanged(cursor.Pass());
+  if (mouse_shape_observer_)

[alexeypa (please no reviews), 2013/04/26 21:33:58]

Can it be NULL?

[Sergey Ulanov, 2013/05/07 22:25:50]

yes

+    mouse_shape_observer_->OnCursorShapeChanged(cursor.Pass());
 }
 
 }  // namespace
 
-scoped_refptr<SharedBuffer> ScreenCapturer::Delegate::CreateSharedBuffer(
-    uint32 size) {
-  return scoped_refptr<SharedBuffer>();
-}
-
-void ScreenCapturer::Delegate::ReleaseSharedBuffer(
-    scoped_refptr<SharedBuffer> buffer) {
-}
-
 // static
 scoped_ptr<ScreenCapturer> ScreenCapturer::Create() {
   return CreateWithDisableAero(true);
 }
 
 // static
 scoped_ptr<ScreenCapturer> ScreenCapturer::CreateWithDisableAero(
     bool disable_aero) {
   return scoped_ptr<ScreenCapturer>(new ScreenCapturerWin(disable_aero));
 }
 
 }  // namespace media