1 /* 2 * Copyright (c) 2013 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 #ifndef WEBRTC_MODULES_DESKTOP_CAPTURE_SCREEN_CAPTURER_H_ 12 #define WEBRTC_MODULES_DESKTOP_CAPTURE_SCREEN_CAPTURER_H_ 13 14 #include <vector> 15 16 #include "webrtc/modules/desktop_capture/desktop_capture_types.h" 17 #include "webrtc/modules/desktop_capture/desktop_capturer.h" 18 #include "webrtc/system_wrappers/interface/scoped_ptr.h" 19 #include "webrtc/typedefs.h" 20 21 namespace webrtc { 22 23 class DesktopCaptureOptions; 24 struct MouseCursorShape; 25 26 // Class used to capture video frames asynchronously. 27 // 28 // The full capture sequence is as follows: 29 // 30 // (1) Start 31 // This is when pre-capture steps are executed, such as flagging the 32 // display to prevent it from sleeping during a session. 33 // 34 // (2) CaptureFrame 35 // This is where the bits for the invalid rects are packaged up and sent 36 // to the encoder. 37 // A screen capture is performed if needed. For example, Windows requires 38 // a capture to calculate the diff from the previous screen, whereas the 39 // Mac version does not. 40 // 41 // Implementation has to ensure the following guarantees: 42 // 1. Double buffering 43 // Since data can be read while another capture action is happening. 44 class ScreenCapturer : public DesktopCapturer { 45 public: 46 // Use a struct to represent a screen although it has only an id for now, 47 // because we may want to add more fields (e.g. description) in the future. 48 struct Screen { 49 ScreenId id; 50 }; 51 typedef std::vector<Screen> ScreenList; 52 53 // Provides callbacks used by the capturer to pass captured video frames and 54 // mouse cursor shapes to the processing pipeline. 55 // 56 // TODO(sergeyu): Move cursor shape capturing to a separate class because it's 57 // unrelated. 58 class MouseShapeObserver { 59 public: 60 // Called when the cursor shape has changed. Must take ownership of 61 // |cursor_shape|. 62 virtual void OnCursorShapeChanged(MouseCursorShape* cursor_shape) = 0; 63 64 protected: 65 virtual ~MouseShapeObserver() {} 66 }; 67 68 virtual ~ScreenCapturer() {} 69 70 // Creates platform-specific capturer. 71 // 72 // TODO(sergeyu): Remove all Create() methods except the first one. 73 // crbug.com/172183 74 static ScreenCapturer* Create(const DesktopCaptureOptions& options); 75 static ScreenCapturer* Create(); 76 77 #if defined(WEBRTC_LINUX) 78 // Creates platform-specific capturer and instructs it whether it should use 79 // X DAMAGE support. 80 static ScreenCapturer* CreateWithXDamage(bool use_x_damage); 81 #elif defined(WEBRTC_WIN) 82 // Creates Windows-specific capturer and instructs it whether or not to 83 // disable desktop compositing. 84 static ScreenCapturer* CreateWithDisableAero(bool disable_aero); 85 #endif // defined(WEBRTC_WIN) 86 87 // Called at the beginning of a capturing session. |mouse_shape_observer| must 88 // remain valid until the capturer is destroyed. 89 virtual void SetMouseShapeObserver( 90 MouseShapeObserver* mouse_shape_observer) = 0; 91 92 // Get the list of screens (not containing kFullDesktopScreenId). Returns 93 // false in case of a failure. 94 virtual bool GetScreenList(ScreenList* screens) = 0; 95 96 // Select the screen to be captured. Returns false in case of a failure (e.g. 97 // if there is no screen with the specified id). If this is never called, the 98 // full desktop is captured. 99 virtual bool SelectScreen(ScreenId id) = 0; 100 }; 101 102 } // namespace webrtc 103 104 #endif // WEBRTC_MODULES_DESKTOP_CAPTURE_SCREEN_CAPTURER_H_ 105
