VCam，可正常编译运行的虚拟摄像头代码

//------------------------------------------------------------------------------ // File: AMFilter.cpp // // Desc: DirectShow base classes - implements class hierarchy for streams // architecture. // // Copyright (c) 1992-2001 Microsoft Corporation. All rights reserved. //------------------------------------------------------------------------------ //===================================================================== //===================================================================== // The following classes are declared in this header: // // // CBaseMediaFilter Basic IMediaFilter support (abstract class) // CBaseFilter Support for IBaseFilter (incl. IMediaFilter) // CEnumPins Enumerate input and output pins // CEnumMediaTypes Enumerate the preferred pin formats // CBasePin Abstract base class for IPin interface // CBaseOutputPin Adds data provider member functions // CBaseInputPin Implements IMemInputPin interface // CMediaSample Basic transport unit for IMemInputPin // CBaseAllocator General list guff for most allocators // CMemAllocator Implements memory buffer allocation // //===================================================================== //===================================================================== #include <streams.h> #include <strsafe.h> #ifdef DXMPERF #include "dxmperf.h" #endif // DXMPERF //===================================================================== // Helpers //===================================================================== STDAPI CreateMemoryAllocator(__deref_out IMemAllocator **ppAllocator) { return CoCreateInstance(CLSID_MemoryAllocator, 0, CLSCTX_INPROC_SERVER, IID_IMemAllocator, (void **)ppAllocator); } // Put this one here rather than in ctlutil.cpp to avoid linking // anything brought in by ctlutil.cpp STDAPI CreatePosPassThru( __in_opt LPUNKNOWN pAgg, BOOL bRenderer, IPin *pPin, __deref_out IUnknown **ppPassThru ) { *ppPassThru = NULL; IUnknown *pUnkSeek; HRESULT hr = CoCreateInstance(CLSID_SeekingPassThru, pAgg, CLSCTX_INPROC_SERVER, IID_IUnknown, (void **)&pUnkSeek ); if (FAILED(hr)) { return hr; } ISeekingPassThru *pPassThru; hr = pUnkSeek->QueryInterface(IID_ISeekingPassThru, (void**)&pPassThru); if (FAILED(hr)) { pUnkSeek->Release(); return hr; } hr = pPassThru->Init(bRenderer, pPin); pPassThru->Release(); if (FAILED(hr)) { pUnkSeek->Release(); return hr; } *ppPassThru = pUnkSeek; return S_OK; } #define CONNECT_TRACE_LEVEL 3 //===================================================================== //===================================================================== // Implements CBaseMediaFilter //===================================================================== //===================================================================== /* Constructor */ CBaseMediaFilter::CBaseMediaFilter(__in_opt LPCTSTR pName, __inout_opt LPUNKNOWN pUnk, __in CCritSec *pLock, REFCLSID clsid) : CUnknown(pName, pUnk), m_pLock(pLock), m_clsid(clsid), m_State(State_Stopped), m_pClock(NULL) { } /* Destructor */ CBaseMediaFilter::~CBaseMediaFilter() { // must be stopped, but can't call Stop here since // our critsec has been destroyed. /* Release any clock we were using */ if (m_pClock) { m_pClock->Release(); m_pClock = NULL; } } /* Override this to say what interfaces we support and where */ STDMETHODIMP CBaseMediaFilter::NonDelegatingQueryInterface( REFIID riid, __deref_out void ** ppv) { if (riid == IID_IMediaFilter) { return GetInterface((IMediaFilter *) this, ppv); } else if (riid == IID_IPersist) { return GetInterface((IPersist *) this, ppv); } else { return CUnknown::NonDelegatingQueryInterface(riid, ppv); } } /* Return the filter's clsid */ STDMETHODIMP CBaseMediaFilter::GetClassID(__out CLSID *pClsID) { CheckPointer(pClsID,E_POINTER); ValidateReadWritePtr(pClsID,sizeof(CLSID)); *pClsID = m_clsid; return NOERROR; } /* Override this if your state changes are not done synchronously */ STDMETHODIMP CBaseMediaFilter::GetState(DWORD dwMSecs, __out FILTER_STATE *State) { UNREFERENCED_PARAMETER(dwMSecs); CheckPointer(State,E_POINTER); ValidateReadWritePtr(State,sizeof(FILTER_STATE)); *State = m_State; return S_OK; } /* Set the clock we will use for synchronisation */ STDMETHODIMP CBaseMediaFilter::SetSyncSource(__inout_opt IReferenceClock *pClock) { CAutoLock cObjectLock(m_pLock); // Ensure the new one does not go away - even if the same as the old if (pClock) { pClock->AddRef(); } // if we have a clock, release it if (m_pClock) { m_pClock->Release(); } // Set the new reference clock (might be NULL) // Should we query it to ensure it is a clock? Consider for a debug build. m_pClock = pClock; return NOERROR; } /* Return the clock we are using for synchronisation */ STDMETHODIMP CBaseMediaFilter::GetSyncSource(__deref_out_opt IReferenceClock **pClock) { CheckPointer(pClock,E_POINTER); ValidateReadWritePtr(pClock,sizeof(IReferenceClock *)); CAutoLock cObjectLock(m_pLock); if (m_pClock) { // returning an interface... addref it... m_pClock->AddRef(); } *pClock = (IReferenceClock*)m_pClock; return NOERROR; } /* Put the filter into a stopped state */ STDMETHODIMP CBaseMediaFilter::Stop() { CAutoLock cObjectLock(m_pLock); m_State = State_Stopped; return S_OK; } /* Put the filter into a paused state */ STDMETHODIMP CBaseMediaFilter::Pause() { CAutoLock cObjectLock(m_pLock); m_State = State_Paused; return S_OK; } // Put the filter into a running state. // The time parameter is the offset to be added to the samples' // stream time to get the reference time at which they should be presented. // // you can either add these two and compare it against the reference clock, // or you can call CBaseMediaFilter::StreamTime and compare that against // the sample timestamp. STDMETHODIMP CBaseMediaFilter::Run(REFERENCE_TIME tStart) { CAutoLock cObjectLock(m_pLock); // remember the stream time offset m_tStart = tStart; if (m_State == State_Stopped){ HRESULT hr = Pause(); if (FAILED(hr)) { return hr; } } m_State = State_Running; return S_OK; } // // return the current stream time - samples with start timestamps of this // time or before should be rendered by now HRESULT CBaseMediaFilter::StreamTime(CRefTime& rtStream) { // Caller must lock for synchronization // We can't grab the filter lock because we want to be able to call // this from worker threads without deadlocking if (m_pClock == NULL) { return VFW_E_NO_CLOCK; } // get the current reference time HRESULT hr = m_pClock->GetTime((REFERENCE_TIME*)&rtStream); if (FAILED(hr)) { return hr; } // subtract the stream offset to get stream time rtStream -= m_tStart; return S_OK; } //====================================================================