力為的技術博客

?1 class ?CCaptureVideo?:? public ?CWnd?
?2 {
?3 ????friend? class ?CSampleGrabberCB;
?4 public :
?5 ???? void ?GrabOneFrame(BOOL?bGrab,? const ?CString & ?szFileName);
?6 ????HRESULT?Init( int ?iDeviceID,HWND?hWnd);
?7 ???? int ?EnumDevices(HWND?hList);
?8 ????CCaptureVideo();
?9 ???? virtual ? ~ CCaptureVideo();
10 private :
11 ????HWND?m_hWnd;
12 ????IGraphBuilder? * m_pGB;
13 ????ICaptureGraphBuilder2 * ?m_pCapture;
14 ????IBaseFilter * ?m_pBF;
15 ????IMediaControl * ?m_pMC;
16 ????IMediaEventEx? * ?m_pME;
17 ????IVideoWindow * ?m_pVW;
18 ????CComPtr < ISampleGrabber > ?m_pGrabber;
19 protected :
20 ???? void ?FreeMediaType(AM_MEDIA_TYPE & ?mt);
21 ???? bool ?BindFilter( int ?deviceId,?IBaseFilter? ** pFilter);
22 ???? void ?ResizeVideoWindow();
23 ????HRESULT?SetupVideoWindow();
24 ????HRESULT?InitCaptureGraphBuilder();
25 } ;

?1
?2 class ?CSampleGrabberCB?:? public ?ISampleGrabberCB?
?3 {
?4 public :
?5 ???? long ?lWidth;
?6 ???? long ?lHeight;
?7 ???? static ?CString?m_szFileName; // ?位圖文件名稱
?8 ????CSampleGrabberCB(?)
?9 ???? {
10 ????} ?
11
12 ????STDMETHODIMP_(ULONG)?AddRef()?
13 ???? {? return ? 2 ;?}
14
15 ????STDMETHODIMP_(ULONG)?Release()?
16 ???? {? return ? 1 ;?}
17
18 ????STDMETHODIMP?QueryInterface(REFIID?riid,? void ? ** ?ppv)
19 ???? {
20 ???????? if (?riid? == ?IID_ISampleGrabberCB? || ?riid? == ?IID_IUnknown?)
21 ???????? {?
22 ???????????? * ppv? = ?( void ? * )?static_cast < ISampleGrabberCB *> ?(? this ?);
23 ???????????? return ?NOERROR;
24 ????????} ?
25 ???????? return ?E_NOINTERFACE;
26 ????}
27
28 ????STDMETHODIMP?SampleCB(? double ?SampleTime,?IMediaSample? * ?pSample?)
29 ???? {
30 ???????? return ? 0 ;
31 ????}
32
33 ????STDMETHODIMP?BufferCB(? double ?dblSampleTime,?BYTE? * ?pBuffer,? long ?lBufferSize?)
34 ???? {
35 ???????? if (? ! bOneShot?) return ? 0 ;
36 ????????
37 ???????? if ?( ! pBuffer)
38 ???????????? return ?E_POINTER;
39
40 ???????? if (SaveBitmap(pBuffer,?lBufferSize))
41 ???????? {
42 ???????????? // ?notify?has?create?a?bitmap?file;
43 ????????????CGlobalData::m_pMainView -> HasSavedPhoto(m_szFileName);
44 ????????}
45
46 ????????bOneShot? = ?FALSE;
47
48 ????
49 ???????? return ? 0 ;
50 ????}
51 ???? // 創建位圖文件
52 ????BOOL?SaveBitmap(BYTE? * ?pBuffer,? long ?lBufferSize?)
53 ???? {
54 ????????HANDLE?hf? = ?CreateFile(
55 ????????????m_szFileName,
56 ????????????GENERIC_WRITE,?FILE_SHARE_READ,?NULL,
57 ????????????CREATE_ALWAYS,
58 ????????????NULL,?
59 ????????????NULL?);
60
61 ???????? if (?hf? == ?INVALID_HANDLE_VALUE?)
62 ???????????? return ?FALSE;
63
64 ???????? // ?寫文件頭?
65 ????????BITMAPFILEHEADER?bfh;
66 ????????memset(? & bfh,? 0 ,? sizeof (?bfh?)?);
67 ????????bfh.bfType? = ? ' MB ' ;
68 ????????bfh.bfSize? = ? sizeof (?bfh?)? + ?lBufferSize? + ? sizeof (?BITMAPINFOHEADER?);
69 ????????bfh.bfOffBits? = ? sizeof (?BITMAPINFOHEADER?)? + ? sizeof (?BITMAPFILEHEADER?);
70 ????????DWORD?dwWritten? = ? 0 ;
71 ????????WriteFile(?hf,? & bfh,? sizeof (?bfh?),? & dwWritten,?NULL?);
72
73 ???????? // ?寫位圖格式
74 ????????BITMAPINFOHEADER?bih;
75 ????????memset(? & bih,? 0 ,? sizeof (?bih?)?);
76 ????????bih.biSize? = ? sizeof (?bih?);
77 ????????bih.biWidth? = ?lWidth;
78 ????????bih.biHeight? = ?lHeight;
79 ????????bih.biPlanes? = ? 1 ;
80 ????????bih.biBitCount? = ? 24 ;
81 ????????WriteFile(?hf,? & bih,? sizeof (?bih?),? & dwWritten,?NULL?);
82
83 ???????? // ?寫位圖數據
84 ????????WriteFile(?hf,?pBuffer,?lBufferSize,? & dwWritten,?NULL?);
85
86 ????????CloseHandle(?hf?);
87
88 ???????? return ?TRUE;
89 ????}
90 } ;

/**/ ///////////////////////////////////////////////////////////////////// /
// ?Construction/Destruction
/**/ ///////////////////////////////////////////////////////////////////// /
CCaptureVideo::CCaptureVideo()
{
????m_pBF? = ? 0 ;
????m_hWnd? = ?NULL;
????m_pVW? = ?NULL;
????m_pMC? = ?NULL;
????m_pME? = ?NULL;
????m_pGB? = ?NULL;
????m_pCapture? = ?NULL;?
}
CCaptureVideo:: ~ CCaptureVideo()
{
???? // ?Stop?media?playback

???? if (m_pMC)
????????m_pMC -> StopWhenReady();
???? // ?Stop?receiving?events
???? if ?(m_pME)
????????m_pME -> SetNotifyWindow(NULL,?WM_GRAPHNOTIFY,? 0 );

???? if (m_pVW) {
????????m_pVW -> put_Visible(OAFALSE);
????????m_pVW -> put_Owner(NULL);
????}


????SAFE_RELEASE(m_pMC);
????SAFE_RELEASE(m_pME);
????SAFE_RELEASE(m_pVW);
????SAFE_RELEASE(m_pGB);
????SAFE_RELEASE(m_pBF);
????SAFE_RELEASE(m_pCapture);
???? // CoUninitialize(?);
}
int ?CCaptureVideo::EnumDevices(HWND?hList)
{
???? if ?( ! hList)
???????? return ? - 1 ;
???? int ?id? = ? 0 ;
????
???? // 枚舉視頻撲捉設備
????ICreateDevEnum? * pCreateDevEnum;
????HRESULT?hr? = ?CoCreateInstance(CLSID_SystemDeviceEnum,?NULL,?CLSCTX_INPROC_SERVER,IID_ICreateDevEnum,?( void ** ) & pCreateDevEnum);
????
???? if ?(hr? != ?NOERROR) return ? - 1 ;
????CComPtr < IEnumMoniker > ?pEm;
????hr? = ?pCreateDevEnum -> CreateClassEnumerator(CLSID_VideoInputDeviceCategory, & pEm,? 0 );
????
???? if ?(hr? != ?NOERROR) return ? - 1 ;
????pEm -> Reset();
????ULONG?cFetched;
????IMoniker? * pM;
???? while (hr? = ?pEm -> Next( 1 ,? & pM,? & cFetched),?hr == S_OK)
???? {
????????IPropertyBag? * pBag;
????????hr? = ?pM -> BindToStorage( 0 ,? 0 ,?IID_IPropertyBag,?( void ? ** ) & pBag);
???????? if (SUCCEEDED(hr))?
???????? {
????????????VARIANT?var;
????????????var.vt? = ?VT_BSTR;
????????????hr? = ?pBag -> Read(L " FriendlyName " ,? & var,?NULL);
???????????? if ?(hr? == ?NOERROR)?
???????????? {
????????????????TCHAR?str[ 2048 ];?
????????????????id ++ ;
????????????????WideCharToMultiByte(CP_ACP, 0 ,var.bstrVal,? - 1 ,?str,? 2048 ,?NULL,?NULL);
????????????????::SendMessage(hList,?CB_ADDSTRING,? 0 ,(LPARAM)str);
????????????????SysFreeString(var.bstrVal);
????????????}
????????????pBag -> Release();
????????}
????????pM -> Release();
????}
???? return ?id;
}
HRESULT?CCaptureVideo::Init( int ?iDeviceID,?HWND?hWnd)
{
????HRESULT?hr;
????hr? = ?InitCaptureGraphBuilder();
???? if ?(FAILED(hr)) {
????????AfxMessageBox( " Failed?to?get?video?interfaces! " );
???????? return ?hr;
????}

???? // ?Bind?Device?Filter.?We?know?the?device?because?the?id?was?passed?in
???? if ( ! BindFilter(iDeviceID,? & m_pBF)) return ?S_FALSE;
????hr? = ?m_pGB -> AddFilter(m_pBF,?L " Video?Capture " );
???? if ?(FAILED(hr))
???? {
????????m_pBF -> Release();
???????? return ?hr;
????}

???? // ?create?a?sample?grabber
????hr? = ?m_pGrabber.CoCreateInstance(?CLSID_SampleGrabber?);
???? if (? ! m_pGrabber?) {
????????AfxMessageBox( " Fail?to?create?SampleGrabber,?maybe?qedit.dll?is?not?registered? " );
???????? return ?hr;
????}
????CComQIPtr < ?IBaseFilter,? & IID_IBaseFilter? > ?pGrabBase(?m_pGrabber?);
????
???? // 設置視頻格式
????AM_MEDIA_TYPE?mt;?
????ZeroMemory( & mt,? sizeof (AM_MEDIA_TYPE));
????mt.majortype? = ?MEDIATYPE_Video;
????mt.subtype? = ?MEDIASUBTYPE_RGB24;
????hr? = ?m_pGrabber -> SetMediaType( & mt);
????
???? if (?FAILED(?hr?)?) {
????????AfxMessageBox( " Fail?to?set?media?type! " );
???????? return ?hr;
????}
????hr? = ?m_pGB -> AddFilter(?pGrabBase,?L " Grabber " ?);
???? if (?FAILED(?hr?)?) {
????????AfxMessageBox( " Fail?to?put?sample?grabber?in?graph " );
???????? return ?hr;
????}
????
???? // ?try?to?render?preview/capture?pin
????hr? = ?m_pCapture -> RenderStream( & PIN_CATEGORY_PREVIEW,? & MEDIATYPE_Video,m_pBF,pGrabBase,NULL);
???? if (?FAILED(?hr?)?)
????????hr? = ?m_pCapture -> RenderStream( & PIN_CATEGORY_CAPTURE,? & MEDIATYPE_Video,m_pBF,pGrabBase,NULL);
????
???? if (?FAILED(?hr?)?) {
????????AfxMessageBox( " Can’t?build?the?graph " );
???????? return ?hr;
??????????}
????
????hr? = ?m_pGrabber -> GetConnectedMediaType(? & mt?);
???? if ?(?FAILED(?hr)?) {
????????AfxMessageBox( " Failt?to?read?the?connected?media?type " );
???????? return ?hr;
????}
????
????VIDEOINFOHEADER? * ?vih? = ?(VIDEOINFOHEADER * )?mt.pbFormat;
????mCB.lWidth? = ?vih -> bmiHeader.biWidth;
????mCB.lHeight? = ?vih -> bmiHeader.biHeight;
????FreeMediaType(mt);
????hr? = ?m_pGrabber -> SetBufferSamples(?FALSE?);
????hr? = ?m_pGrabber -> SetOneShot(?FALSE?);
????hr? = ?m_pGrabber -> SetCallback(? & mCB,? 1 ?);
????
???? // 設置視頻捕捉窗口
????m_hWnd? = ?hWnd?;?
????SetupVideoWindow();

????hr? = ?m_pMC -> Run(); // 開始視頻捕捉
???? if (FAILED(hr))
???? {
????????AfxMessageBox( " Couldn’t?run?the?graph! " );
???????? return ?hr;
????}

???? return ?S_OK;
}
bool ?CCaptureVideo::BindFilter( int ?deviceId,?IBaseFilter? ** pFilter)
{
???? if ?(deviceId? < ? 0 )
???????? return ? false ;
????IBaseFilter? * ?pSrc? = ?NULL;
???? // ?enumerate?all?video?capture?devices
????CComPtr < ICreateDevEnum > ?pCreateDevEnum? = ?NULL;
????HRESULT?hr? = ?CoCreateInstance(CLSID_SystemDeviceEnum,?NULL,?CLSCTX_INPROC,
????????IID_ICreateDevEnum,?( void ** ) & pCreateDevEnum);
???? if ?(FAILED(hr))
???? {
???????? return ? false ;
????}
????CComPtr < IEnumMoniker > ?pEm? = ?NULL;
????hr? = ?pCreateDevEnum -> CreateClassEnumerator(CLSID_VideoInputDeviceCategory, & pEm,? 0 );
???? if ?(FAILED(hr))?
???? {
???????? return ? false ;
????}
???? // pEm->Reset();

????ULONG?cFetched;
????IMoniker? * pM;
???? int ?index? = ? 0 ;
???? while (S_OK? == ?(pEm -> Next( 1 ,? & pM,? & cFetched))? && ?index? <= ?deviceId)
???? {
????????IPropertyBag? * pBag;
????????hr? = ?pM -> BindToStorage( 0 ,? 0 ,?IID_IPropertyBag,?( void ? ** ) & pBag);
???????? if (SUCCEEDED(hr))?
???????? {
????????????VARIANT?var;
????????????var.vt? = ?VT_BSTR;
????????????hr? = ?pBag -> Read(L " FriendlyName " ,? & var,?NULL);
???????????? if ?(hr? == ?NOERROR)?
???????????? {
???????????????? if ?(index? == ?deviceId)
???????????????? {
????????????????????pM -> BindToObject( 0 ,? 0 ,?IID_IBaseFilter,?( void ** ) & pSrc);
????????????????}
????????????????SysFreeString(var.bstrVal);
????????????}
????????????pBag -> Release();
????????}
????????pM -> Release();
????????index ++ ;
????}

???? * pFilter? = ?pSrc;
???? return ? true ;
}

HRESULT?CCaptureVideo::InitCaptureGraphBuilder()
{
????HRESULT?hr;
????
???? // ?創建IGraphBuilder接口
????hr = CoCreateInstance(CLSID_FilterGraph,?NULL,?CLSCTX_INPROC,
????????IID_IGraphBuilder,?( void ? ** ) & m_pGB);
???? if ?(FAILED(hr))
???????? return ?hr;

???? // ?創建ICaptureGraphBuilder2接口
????hr? = ?CoCreateInstance?(CLSID_CaptureGraphBuilder2?,?NULL,?CLSCTX_INPROC,
????????IID_ICaptureGraphBuilder2,?( void ? ** )? & m_pCapture);
???? if ?(FAILED(hr))
???????? return ?hr;

????m_pCapture -> SetFiltergraph(m_pGB);
????hr? = ?m_pGB -> QueryInterface(IID_IMediaControl,?( void ? ** ) & m_pMC);
???? if ?(FAILED(hr))
???????? return ?hr;

????hr? = ?m_pGB -> QueryInterface(IID_IVideoWindow,?(LPVOID? * )? & m_pVW);
???? if ?(FAILED(hr))
???????? return ?hr;

????hr? = ?m_pGB -> QueryInterface(IID_IMediaEvent,?(LPVOID? * )? & m_pME);
???? if ?(FAILED(hr))
???????? return ?hr;

???? // ?Set?the?window?handle?used?to?process?graph?events
????hr? = ?m_pME -> SetNotifyWindow((OAHWND)m_hWnd,?WM_GRAPHNOTIFY,? 0 );

???? return ?hr;
}
HRESULT?CCaptureVideo::SetupVideoWindow()
{
????HRESULT?hr;
????hr? = ?m_pVW -> put_Owner((OAHWND)m_hWnd);
???? if ?(FAILED(hr))
???????? return ?hr;

????hr? = ?m_pVW -> put_WindowStyle(WS_CHILD? | ?WS_CLIPCHILDREN);
???? if ?(FAILED(hr))
???????? return ?hr;

????ResizeVideoWindow();
????hr? = ?m_pVW -> put_Visible(OATRUE);

???? return ?hr;
}
void ?CCaptureVideo::ResizeVideoWindow()
{
???? if ?(m_pVW) {
???????? // 讓圖像充滿整個窗口
????????CRect?rc;
????????::GetClientRect(m_hWnd, & rc);
????????m_pVW -> SetWindowPosition( 0 ,? 0 ,?rc.right,?rc.bottom);
????} ?
}
void ?CCaptureVideo::GrabOneFrame(BOOL?bGrab,? const ?CString & ?szFileName)
{
????bOneShot? = ?bGrab;
????CSampleGrabberCB::m_szFileName? = ?szFileName;
}
void ?CCaptureVideo::FreeMediaType(AM_MEDIA_TYPE & ?mt)
{
???? if ?(mt.cbFormat? != ? 0 )? {
????????CoTaskMemFree((PVOID)mt.pbFormat);
???????? // ?Strictly?unnecessary?but?tidier
????????mt.cbFormat? = ? 0 ;
????????mt.pbFormat? = ?NULL;
????}
???? if ?(mt.pUnk? != ?NULL)? {
????????mt.pUnk -> Release();
????????mt.pUnk? = ?NULL;
????}
} ?