gstreamer/subprojects/gst-plugins-bad/sys/directshow/strmbase/baseclasses/transfrm.h

304 lines
9.6 KiB
C++

//------------------------------------------------------------------------------
// File: Transfrm.h
//
// Desc: DirectShow base classes - defines classes from which simple
// transform codecs may be derived.
//
// Copyright (c) 1992-2001 Microsoft Corporation. All rights reserved.
//------------------------------------------------------------------------------
// It assumes the codec has one input and one output stream, and has no
// interest in memory management, interface negotiation or anything else.
//
// derive your class from this, and supply Transform and the media type/format
// negotiation functions. Implement that class, compile and link and
// you're done.
#ifndef __TRANSFRM__
#define __TRANSFRM__
// ======================================================================
// This is the com object that represents a simple transform filter. It
// supports IBaseFilter, IMediaFilter and two pins through nested interfaces
// ======================================================================
class CTransformFilter;
// ==================================================
// Implements the input pin
// ==================================================
class CTransformInputPin : public CBaseInputPin
{
friend class CTransformFilter;
protected:
CTransformFilter *m_pTransformFilter;
public:
CTransformInputPin(
__in_opt LPCTSTR pObjectName,
__inout CTransformFilter *pTransformFilter,
__inout HRESULT * phr,
__in_opt LPCWSTR pName);
#ifdef UNICODE
CTransformInputPin(
__in_opt LPCSTR pObjectName,
__inout CTransformFilter *pTransformFilter,
__inout HRESULT * phr,
__in_opt LPCWSTR pName);
#endif
STDMETHODIMP QueryId(__deref_out LPWSTR * Id)
{
return AMGetWideString(L"In", Id);
}
// Grab and release extra interfaces if required
HRESULT CheckConnect(IPin *pPin);
HRESULT BreakConnect();
HRESULT CompleteConnect(IPin *pReceivePin);
// check that we can support this output type
HRESULT CheckMediaType(const CMediaType* mtIn);
// set the connection media type
HRESULT SetMediaType(const CMediaType* mt);
// --- IMemInputPin -----
// here's the next block of data from the stream.
// AddRef it yourself if you need to hold it beyond the end
// of this call.
STDMETHODIMP Receive(IMediaSample * pSample);
// provide EndOfStream that passes straight downstream
// (there is no queued data)
STDMETHODIMP EndOfStream(void);
// passes it to CTransformFilter::BeginFlush
STDMETHODIMP BeginFlush(void);
// passes it to CTransformFilter::EndFlush
STDMETHODIMP EndFlush(void);
STDMETHODIMP NewSegment(
REFERENCE_TIME tStart,
REFERENCE_TIME tStop,
double dRate);
// Check if it's OK to process samples
virtual HRESULT CheckStreaming();
// Media type
public:
CMediaType& CurrentMediaType() { return m_mt; };
};
// ==================================================
// Implements the output pin
// ==================================================
class CTransformOutputPin : public CBaseOutputPin
{
friend class CTransformFilter;
protected:
CTransformFilter *m_pTransformFilter;
public:
// implement IMediaPosition by passing upstream
IUnknown * m_pPosition;
CTransformOutputPin(
__in_opt LPCTSTR pObjectName,
__inout CTransformFilter *pTransformFilter,
__inout HRESULT * phr,
__in_opt LPCWSTR pName);
#ifdef UNICODE
CTransformOutputPin(
__in_opt LPCSTR pObjectName,
__inout CTransformFilter *pTransformFilter,
__inout HRESULT * phr,
__in_opt LPCWSTR pName);
#endif
~CTransformOutputPin();
// override to expose IMediaPosition
STDMETHODIMP NonDelegatingQueryInterface(REFIID riid, __deref_out void **ppv);
// --- CBaseOutputPin ------------
STDMETHODIMP QueryId(__deref_out LPWSTR * Id)
{
return AMGetWideString(L"Out", Id);
}
// Grab and release extra interfaces if required
HRESULT CheckConnect(IPin *pPin);
HRESULT BreakConnect();
HRESULT CompleteConnect(IPin *pReceivePin);
// check that we can support this output type
HRESULT CheckMediaType(const CMediaType* mtOut);
// set the connection media type
HRESULT SetMediaType(const CMediaType *pmt);
// called from CBaseOutputPin during connection to ask for
// the count and size of buffers we need.
HRESULT DecideBufferSize(
IMemAllocator * pAlloc,
__inout ALLOCATOR_PROPERTIES *pProp);
// returns the preferred formats for a pin
HRESULT GetMediaType(int iPosition, __inout CMediaType *pMediaType);
// inherited from IQualityControl via CBasePin
STDMETHODIMP Notify(IBaseFilter * pSender, Quality q);
// Media type
public:
CMediaType& CurrentMediaType() { return m_mt; };
};
class AM_NOVTABLE CTransformFilter : public CBaseFilter
{
public:
// map getpin/getpincount for base enum of pins to owner
// override this to return more specialised pin objects
virtual int GetPinCount();
virtual CBasePin * GetPin(int n);
STDMETHODIMP FindPin(LPCWSTR Id, __deref_out IPin **ppPin);
// override state changes to allow derived transform filter
// to control streaming start/stop
STDMETHODIMP Stop();
STDMETHODIMP Pause();
public:
CTransformFilter(__in_opt LPCTSTR , __inout_opt LPUNKNOWN, REFCLSID clsid);
#ifdef UNICODE
CTransformFilter(__in_opt LPCSTR , __inout_opt LPUNKNOWN, REFCLSID clsid);
#endif
~CTransformFilter();
// =================================================================
// ----- override these bits ---------------------------------------
// =================================================================
// These must be supplied in a derived class
virtual HRESULT Transform(IMediaSample * pIn, IMediaSample *pOut);
// check if you can support mtIn
virtual HRESULT CheckInputType(const CMediaType* mtIn) PURE;
// check if you can support the transform from this input to this output
virtual HRESULT CheckTransform(const CMediaType* mtIn, const CMediaType* mtOut) PURE;
// this goes in the factory template table to create new instances
// static CCOMObject * CreateInstance(__inout_opt LPUNKNOWN, HRESULT *);
// call the SetProperties function with appropriate arguments
virtual HRESULT DecideBufferSize(
IMemAllocator * pAllocator,
__inout ALLOCATOR_PROPERTIES *pprop) PURE;
// override to suggest OUTPUT pin media types
virtual HRESULT GetMediaType(int iPosition, __inout CMediaType *pMediaType) PURE;
// =================================================================
// ----- Optional Override Methods -----------------------
// =================================================================
// you can also override these if you want to know about streaming
virtual HRESULT StartStreaming();
virtual HRESULT StopStreaming();
// override if you can do anything constructive with quality notifications
virtual HRESULT AlterQuality(Quality q);
// override this to know when the media type is actually set
virtual HRESULT SetMediaType(PIN_DIRECTION direction,const CMediaType *pmt);
// chance to grab extra interfaces on connection
virtual HRESULT CheckConnect(PIN_DIRECTION dir,IPin *pPin);
virtual HRESULT BreakConnect(PIN_DIRECTION dir);
virtual HRESULT CompleteConnect(PIN_DIRECTION direction,IPin *pReceivePin);
// chance to customize the transform process
virtual HRESULT Receive(IMediaSample *pSample);
// Standard setup for output sample
HRESULT InitializeOutputSample(IMediaSample *pSample, __deref_out IMediaSample **ppOutSample);
// if you override Receive, you may need to override these three too
virtual HRESULT EndOfStream(void);
virtual HRESULT BeginFlush(void);
virtual HRESULT EndFlush(void);
virtual HRESULT NewSegment(
REFERENCE_TIME tStart,
REFERENCE_TIME tStop,
double dRate);
#ifdef PERF
// Override to register performance measurement with a less generic string
// You should do this to avoid confusion with other filters
virtual void RegisterPerfId()
{m_idTransform = MSR_REGISTER(TEXT("Transform"));}
#endif // PERF
// implementation details
protected:
#ifdef PERF
int m_idTransform; // performance measuring id
#endif
BOOL m_bEOSDelivered; // have we sent EndOfStream
BOOL m_bSampleSkipped; // Did we just skip a frame
BOOL m_bQualityChanged; // Have we degraded?
// critical section protecting filter state.
CCritSec m_csFilter;
// critical section stopping state changes (ie Stop) while we're
// processing a sample.
//
// This critical section is held when processing
// events that occur on the receive thread - Receive() and EndOfStream().
//
// If you want to hold both m_csReceive and m_csFilter then grab
// m_csFilter FIRST - like CTransformFilter::Stop() does.
CCritSec m_csReceive;
// these hold our input and output pins
friend class CTransformInputPin;
friend class CTransformOutputPin;
CTransformInputPin *m_pInput;
CTransformOutputPin *m_pOutput;
};
#endif /* __TRANSFRM__ */