手機視頻研究系列（1）

 

在windowsmobile下進行視頻採集，我採用的directshow進行實現。

我的開發環境是vs2005，用的開發語言爲C++，做正兒八經的事情，我還是傾向於使用C++來做，當然用directshow可能最好用C++比較好。

我開發電腦上安裝的是windowsmobile sdk 6.0。在安裝好了SDK後，在c:/Program Files/Windows Mobile 6SDK/Samples/PocketPC/CPP/win32/CameraCapture/目錄下有個視頻採集的例子，打開就可以編譯。如果編譯過程中出現如下錯誤：

錯誤       1     errorLNK2001: 無法解析的外部符號IID_IMediaEvent  graphmanager.obj  

錯誤       2     errorLNK2001: 無法解析的外部符號PIN_CATEGORY_STILL    graphmanager.obj  

錯誤       3     errorLNK2001: 無法解析的外部符號CLSID_IMGSinkFilter  graphmanager.obj  

錯誤       4     errorLNK2001: 無法解析的外部符號PIN_CATEGORY_CAPTURE      graphmanager.obj  

錯誤       5     errorLNK2001: 無法解析的外部符號MEDIATYPE_Video     graphmanager.obj  

錯誤       6     errorLNK2001: 無法解析的外部符號MEDIASUBTYPE_Asf graphmanager.obj  

錯誤       7     errorLNK2001: 無法解析的外部符號DMOCATEGORY_VIDEO_ENCODER      graphmanager.obj  

錯誤       8     errorLNK2001: 無法解析的外部符號CLSID_DMOWrapperFilter  graphmanager.obj  

錯誤       9     errorLNK2001: 無法解析的外部符號CLSID_VideoCapture   graphmanager.obj  

錯誤       10    errorLNK2001: 無法解析的外部符號CLSID_FilterGraph      graphmanager.obj  

錯誤       11    errorLNK2001: 無法解析的外部符號CLSID_CaptureGraphBuilder      graphmanager.obj  

錯誤       12    fatalerror LNK1120: 11 個無法解析的外部命令       Windows Mobile 6Professional SDK   

不用着急，我也遇到了這樣的情況，可能跟DIRECTX的安裝有些關係，請調整vs2005的編譯環境設置，“工具/選項/項目和解決方案/VC++目錄/”，平臺選windows mobile 6 professional，庫文件中將“C:/Program Files/WindowsMobile 6 SDK/PocketPC/lib/ARMV4I”調整到最上面，然後編譯就應該就可以編譯通過了。

我的測試真機爲S900，顯示出來的按鈕顯示不正常，我對appwindow.cpp做了部分調整如下：

HRESULT CAppWindow::CreateControls( HINSTANCE hInstance ) { HRESULT hr = S_OK; WNDCLASS wndClass; ATOM classAtom; LONG lReturn; RECT rcWorkArea; // First, let's register the window class ZeroMemory( &wndClass, sizeof( wndClass )); wndClass.lpfnWndProc = CAppWindow::AppWindowProc; wndClass.hInstance = hInstance; wndClass.lpszClassName = L"Camera Recording Video Class"; classAtom = RegisterClass( &wndClass ); if( classAtom == NULL ) { ERR( HRESULT_FROM_WIN32( GetLastError() )); } // Now, create the main window SystemParametersInfo(SPI_GETWORKAREA, 0, &rcWorkArea, 0); m_hwnd = CreateWindow( L"Camera Recording Video Class", L"Main Window", WS_VISIBLE, rcWorkArea.left, rcWorkArea.top, rcWorkArea.right - rcWorkArea.left, rcWorkArea.bottom - rcWorkArea.top, NULL, NULL, hInstance, (PVOID) this ); if( m_hwnd == NULL ) { ERR( HRESULT_FROM_WIN32( GetLastError() )); } // Workaround for bug in SetWindowLong, call twice the API lReturn = SetWindowLong( m_hwnd, GWL_USERDATA, (LONG) this ); lReturn = SetWindowLong( m_hwnd, GWL_USERDATA, (LONG) this ); if( lReturn == NULL ) { ERR( HRESULT_FROM_WIN32( GetLastError() )); } // Create a "Start Capture" button and add it to the main window m_startButtonHwnd = CreateWindow( L"Button", L"Start Video Recording", WS_CHILD | WS_VISIBLE | BS_CENTER | BS_PUSHBUTTON | BS_VCENTER, 30, 10, 390, 50, m_hwnd, (HMENU) CMD_START_RECORD_VIDEO, hInstance, NULL ); if( m_startButtonHwnd == NULL ) { ERR( HRESULT_FROM_WIN32( GetLastError() )); } // Create a "Stop Capture" button and add it to the main window m_stopButtonHwnd = CreateWindow( L"Button", L"Stop Video Recording", WS_CHILD | WS_VISIBLE | BS_CENTER | BS_PUSHBUTTON | BS_VCENTER, 30, 70, 390, 50, m_hwnd, (HMENU) CMD_STOP_RECORD_VIDEO, hInstance, NULL ); if( m_startButtonHwnd == NULL ) { ERR( HRESULT_FROM_WIN32( GetLastError() )); } // The stop capture button is disabled by default EnableWindow( m_stopButtonHwnd, FALSE ); // Create the take still image button m_stillButtonHwnd = CreateWindow( L"Button", L"Take a still image", WS_CHILD | WS_VISIBLE | BS_CENTER | BS_PUSHBUTTON | BS_VCENTER, 30, 130, 390, 50, m_hwnd, (HMENU) CMD_STILL_IMAGE, hInstance, NULL ); if( m_startButtonHwnd == NULL ) { ERR( HRESULT_FROM_WIN32( GetLastError() )); } // Create the graph manager. This will control the dshow capture pipeline m_pGraphManager = new CGraphManager(); if( m_pGraphManager == NULL ) { ERR( E_OUTOFMEMORY ); } CHK( m_pGraphManager->RegisterNotificationWindow( m_hwnd )); CHK( m_pGraphManager->Init()); CHK( m_pGraphManager->BuildCaptureGraph()); Cleanup: return hr; } 

運行效果：