blob: 680bac3ff815e4fea02afd1d9557006fba0dedd1 [file] [log] [blame]
* Copyright (c) 2014 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 <memory>
#include <windows.h>
#include <magnification.h>
#include <wincodec.h>
#include "webrtc/modules/desktop_capture/desktop_capturer.h"
#include "webrtc/modules/desktop_capture/screen_capture_frame_queue.h"
#include "webrtc/modules/desktop_capture/screen_capturer_helper.h"
#include "webrtc/modules/desktop_capture/shared_desktop_frame.h"
#include "webrtc/modules/desktop_capture/win/scoped_thread_desktop.h"
#include "webrtc/rtc_base/constructormagic.h"
#include "webrtc/system_wrappers/include/atomic32.h"
namespace webrtc {
class DesktopFrame;
class DesktopRect;
// Captures the screen using the Magnification API to support window exclusion.
// Each capturer must run on a dedicated thread because it uses thread local
// storage for redirecting the library callback. Also the thread must have a UI
// message loop to handle the window messages for the magnifier window.
// This class does not detect DesktopFrame::updated_region(), the field is
// always set to the entire frame rectangle. ScreenCapturerDifferWrapper should
// be used if that functionality is necessary.
class ScreenCapturerWinMagnifier : public DesktopCapturer {
~ScreenCapturerWinMagnifier() override;
// Overridden from ScreenCapturer:
void Start(Callback* callback) override;
void SetSharedMemoryFactory(
std::unique_ptr<SharedMemoryFactory> shared_memory_factory) override;
void CaptureFrame() override;
bool GetSourceList(SourceList* screens) override;
bool SelectSource(SourceId id) override;
void SetExcludedWindow(WindowId window) override;
typedef BOOL(WINAPI* MagImageScalingCallback)(HWND hwnd,
void* srcdata,
void* destdata,
RECT unclipped,
RECT clipped,
HRGN dirty);
typedef BOOL(WINAPI* MagInitializeFunc)(void);
typedef BOOL(WINAPI* MagUninitializeFunc)(void);
typedef BOOL(WINAPI* MagSetWindowSourceFunc)(HWND hwnd, RECT rect);
typedef BOOL(WINAPI* MagSetWindowFilterListFunc)(HWND hwnd,
DWORD dwFilterMode,
int count,
typedef BOOL(WINAPI* MagSetImageScalingCallbackFunc)(
HWND hwnd,
MagImageScalingCallback callback);
static BOOL WINAPI OnMagImageScalingCallback(HWND hwnd,
void* srcdata,
void* destdata,
RECT unclipped,
RECT clipped,
HRGN dirty);
// Captures the screen within |rect| in the desktop coordinates. Returns true
// if succeeded.
// It can only capture the primary screen for now. The magnification library
// crashes under some screen configurations (e.g. secondary screen on top of
// primary screen) if it tries to capture a non-primary screen. The caller
// must make sure not calling it on non-primary screens.
bool CaptureImage(const DesktopRect& rect);
// Helper method for setting up the magnifier control. Returns true if
// succeeded.
bool InitializeMagnifier();
// Called by OnMagImageScalingCallback to output captured data.
void OnCaptured(void* data, const MAGIMAGEHEADER& header);
// Makes sure the current frame exists and matches |size|.
void CreateCurrentFrameIfNecessary(const DesktopSize& size);
static Atomic32 tls_index_;
Callback* callback_ = nullptr;
std::unique_ptr<SharedMemoryFactory> shared_memory_factory_;
ScreenId current_screen_id_ = kFullDesktopScreenId;
std::wstring current_device_key_;
HWND excluded_window_ = NULL;
// Queue of the frames buffers.
ScreenCaptureFrameQueue<SharedDesktopFrame> queue_;
ScopedThreadDesktop desktop_;
// Used for getting the screen dpi.
HDC desktop_dc_ = NULL;
HMODULE mag_lib_handle_ = NULL;
MagInitializeFunc mag_initialize_func_ = nullptr;
MagUninitializeFunc mag_uninitialize_func_ = nullptr;
MagSetWindowSourceFunc set_window_source_func_ = nullptr;
MagSetWindowFilterListFunc set_window_filter_list_func_ = nullptr;
MagSetImageScalingCallbackFunc set_image_scaling_callback_func_ = nullptr;
// The hidden window hosting the magnifier control.
HWND host_window_ = NULL;
// The magnifier control that captures the screen.
HWND magnifier_window_ = NULL;
// True if the magnifier control has been successfully initialized.
bool magnifier_initialized_ = false;
// True if the last OnMagImageScalingCallback was called and handled
// successfully. Reset at the beginning of each CaptureImage call.
bool magnifier_capture_succeeded_ = true;
} // namespace webrtc