c++ 录制电脑屏幕桌面

1：调用windows GDI

bool WindowsGDI::init(int idx) {
 
		mHWinSta = GetProcessWindowStation();
		if (!mHWinSta) {
			LOGE("%s GetProcessWindowStation error", getCapture());
			return false;
		}
 
		mHWnd = GetDesktopWindow();//GetActiveWindow();
		mWndHDC = GetDC(mHWnd);
 
		//初始化GDI
		Gdiplus::GdiplusStartupInput gdiplusStartupInput;
		if (Gdiplus::GdiplusStartup(&mGdiplusToken, &gdiplusStartupInput, nullptr) != Gdiplus::Ok)
		{
			LOGE("%s Gdiplus::GdiplusStartup error", getCapture());
			return false;
		}
 
		mCaptureHDC = CreateCompatibleDC(mWndHDC);
		mCaptureHBitmap = CreateCompatibleBitmap(mWndHDC, mWidth, mHeight);
		SelectObject(mCaptureHDC, mCaptureHBitmap);//将位图选入创建好的兼容句柄
 
		
		mBmpInfo.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
		mBmpInfo.bmiHeader.biWidth = mWidth;
		mBmpInfo.bmiHeader.biHeight = -mHeight;
		mBmpInfo.bmiHeader.biPlanes = 1;
		mBmpInfo.bmiHeader.biBitCount = 24;
		mBmpInfo.bmiHeader.biCompression = BI_RGB;
		mBmpInfo.bmiHeader.biSizeImage = 0;
		mBmpInfo.bmiHeader.biXPelsPerMeter = 0;
		mBmpInfo.bmiHeader.biYPelsPerMeter = 0;
		mBmpInfo.bmiHeader.biClrUsed = 0;
		mBmpInfo.bmiHeader.biClrImportant = 0;
 
		mRGB_size = mWidth * mHeight * 3;//24位图像大小
		mRGB = (PRGBTRIPLE)malloc(mRGB_size);
 
		//通过接口获取屏幕宽高，不准确
		//mFactWidth = GetSystemMetrics(SM_CXSCREEN);
		//mFactHeight = GetSystemMetrics(SM_CYSCREEN);
 
		mFactWidth = mWidth;
		mFactHeight = mHeight;
		return true;
	}

2:获取视频帧

	bool WindowsGDI::getFrame(uint8_t* buffer, int& size, int64_t& timestamp) 
	{
		timestamp = getCurTimestamp();
		BitBlt(mCaptureHDC, 0, 0, mWidth, mHeight, mWndHDC, 0, 0, SRCCOPY);
 
		GetDIBits(mCaptureHDC,mCaptureHBitmap,
			0, mHeight, mRGB, (LPBITMAPINFO)&mBmpInfo, DIB_RGB_COLORS);
 
		memcpy(buffer, mRGB, mRGB_size);
		size = mRGB_size;
 
		return true;
	}

3：保存视频帧到文件