// return the same pin both times.
    HRESULT FindPin(
        [in, string] LPCWSTR Id,
        [out] IPin ** ppPin
    );

    // find out information about this filter
    typedef struct _FilterInfo {
    WCHAR achName[MAX_FILTER_NAME]; // maybe null if not part of graph
        IFilterGraph * pGraph;                   // null if not part of graph
    } FILTER_INFO;

    HRESULT QueryFilterInfo(
        [out] FILTER_INFO * pInfo
    );

    // notify a filter that it has joined a filter graph. It is permitted to
    // refuse. The filter should addref and store this interface for later use
    // since it may need to notify events to this interface. A null pointer indicates
    // that the filter is no longer part of a graph.
    HRESULT JoinFilterGraph(
        [in] IFilterGraph * pGraph,
        [in, string] LPCWSTR pName
    );

    // return a Vendor information string. Optional - may return E_NOTIMPL.
    // memory returned should be freed using CoTaskMemFree
    HRESULT QueryVendorInfo(
        [out, string] LPWSTR* pVendorInfo
    );
}

typedef IBaseFilter *PFILTER;


//=====================================================================
//=====================================================================
// sync and state management
//=====================================================================
//=====================================================================


//=====================================================================
//=====================================================================
// Defines IReferenceClock interface
//=====================================================================
//=====================================================================

[
        object,
        uuid(56a86897-0ad4-11ce-b03a-0020af0ba770),
        pointer_default(unique)
]
interface IReferenceClock : IUnknown {

    // get the time now
    HRESULT GetTime(
        [out] REFERENCE_TIME *pTime
    );

    // ask for an async notification that a time has elapsed
    HRESULT AdviseTime(
        [in] REFERENCE_TIME baseTime,       // base reference time
        [in] REFERENCE_TIME streamTime,     // stream offset time
    [in] HEVENT hEvent,                     // advise via this event
        [out] DWORD_PTR * pdwAdviseCookie   // where your cookie goes
    );

    // ask for an async periodic notification that a time has elapsed
    HRESULT AdvisePeriodic(
        [in] REFERENCE_TIME startTime,      // starting at this time
        [in] REFERENCE_TIME periodTime,     // time between notifications
        [in] HSEMAPHORE hSemaphore,         // advise via a semaphore
    [out] DWORD_PTR * pdwAdviseCookie       // where your cookie goes
    );

    // cancel a request for notification
    HRESULT Unadvise(
        [in] DWORD_PTR dwAdviseCookie);
}

typedef IReferenceClock *PREFERENCECLOCK;

//=====================================================================
//=====================================================================
// Defines IReferenceClock2 interface
//=====================================================================
//=====================================================================

[
        object,
        uuid(36b73885-c2c8-11cf-8b46-00805f6cef60),
        pointer_default(unique)
]
interface IReferenceClock2 : IReferenceClock {
}

typedef IReferenceClock2 *PREFERENCECLOCK2;


//=====================================================================
//=====================================================================
// Data transport interfaces
//=====================================================================
//=====================================================================


//=====================================================================
//=====================================================================
// Defines IMediaSample interface
//=====================================================================
//=====================================================================

[
        local,
        object,
        uuid(56a8689a-0ad4-11ce-b03a-0020af0ba770),
        pointer_default(unique)
]
interface IMediaSample : IUnknown {

    // get me a read/write pointer to this buffer's memory. I will actually
    // want to use sizeUsed bytes.
    HRESULT GetPointer([out] BYTE ** ppBuffer);

    // return the size in bytes of the buffer data area
    long GetSize(void);

    // get the stream time at which this sample should start and finish.
    HRESULT GetTime(
        [out] REFERENCE_TIME * pTimeStart,  // put time here
        [out] REFERENCE_TIME * pTimeEnd
    );

    // Set the stream time at which this sample should start and finish.
    // pTimeStart==pTimeEnd==NULL will invalidate the time stamps in
    // this sample
    HRESULT SetTime(
        [in] REFERENCE_TIME * pTimeStart,   // put time here
        [in] REFERENCE_TIME * pTimeEnd
    );

    // sync-point property. If true, then the beginning of this
    // sample is a sync-point. (note that if AM_MEDIA_TYPE.bTemporalCompression
    // is false then all samples are sync points). A filter can start
    // a stream at any sync point.  S_FALSE if not sync-point, S_OK if true.

    HRESULT IsSyncPoint(void);
    HRESULT SetSyncPoint(BOOL bIsSyncPoint);

    // preroll property.  If true, this sample is for preroll only and
    // shouldn't be displayed.
    HRESULT IsPreroll(void);
    HRESULT SetPreroll(BOOL bIsPreroll);

    long GetActualDataLength(void);
    HRESULT SetActualDataLength(long);

    // these allow for limited format changes in band - if no format change
    // has been made when you receive a sample GetMediaType will return S_FALSE

    HRESULT GetMediaType(AM_MEDIA_TYPE **ppMediaType);
    HRESULT SetMediaType(AM_MEDIA_TYPE *pMediaType);

    // returns S_OK if there is a discontinuity in the data (this frame is
    // not a continuation of the previous stream of data
    // - there has been a seek or some dropped samples).
    HRESULT IsDiscontinuity(void);
    // set the discontinuity property - TRUE if this sample is not a
    // continuation, but a new sample after a seek or a dropped sample.
    HRESULT SetDiscontinuity(BOOL bDiscontinuity);

    // get the media times for this sample
    HRESULT GetMediaTime(
        [out] LONGLONG * pTimeStart,
        [out] LONGLONG * pTimeEnd
    );

    // Set the media times for this sample
    // pTimeStart==pTimeEnd==NULL will invalidate the media time stamps in
    // this sample
    HRESULT SetMediaTime(
        [in] LONGLONG * pTimeStart,
        [in] LONGLONG * pTimeEnd
    );
}

typedef IMediaSample *PMEDIASAMPLE;

//  Values for dwFlags for AM_SAMPLE_PROPERTIES
enum tagAM_SAMPLE_PROPERTY_FLAGS
     { AM_SAMPLE_SPLICEPOINT        = 0x01,   /* Is this a splice point
                                                 IE can it be decoded
                                                 without reference to
                                                 previous data */
       AM_SAMPLE_PREROLL            = 0x02,   /* Is this a preroll sample */
       AM_SAMPLE_DATADISCONTINUITY  = 0x04,   /* Set if start of new segment */
       AM_SAMPLE_TYPECHANGED        = 0x08,   /* Has the type changed */
       AM_SAMPLE_TIMEVALID          = 0x10,   /* Set if time is valid */
       AM_SAMPLE_TIMEDISCONTINUITY  = 0x40,   /* time gap in data starts after
                                                 this sample - pbBuffer can
                                                 be NULL
                                              */
       AM_SAMPLE_FLUSH_ON_PAUSE     = 0x80,   /*  For live data - discard
                                                  in paused state
                                              */
       AM_SAMPLE_STOPVALID          = 0x100,  /*  Stop time is valid */
       AM_SAMPLE_ENDOFSTREAM        = 0x200,  /*  End of stream after
                                                  this data
                                                  This is reserved for
                                                  kernel streaming and is
                                                  not currently used by
                                                  ActiveMovie
                                              */
       AM_STREAM_MEDIA              = 0,      /*  Normal data stream id */
       AM_STREAM_CONTROL            = 1       /*  Control stream id */
                                              /*  > 7FFFFFFF is application
                                                  defined stream
                                              */
     };

//  Media sample generic properties structure
typedef struct tagAM_SAMPLE2_PROPERTIES {
    DWORD    cbData;         //  Length of generic data for extensiblity
                             //  Number of bytes INCLUDING this field
    DWORD    dwTypeSpecificFlags; // Type specific flag data
    DWORD    dwSampleFlags;  //  Flags bits defined by  AM_SAMPLE_xxx flags
                             //  All undefined bits RESERVED (set to 0,
                             //  leave on copy)
    LONG     lActual;        //  Length of data in buffer
    REFERENCE_TIME tStart;   //  Start time if valid
    REFERENCE_TIME tStop;    //  Stop time if valid
    DWORD    dwStreamId;     //  Stream 0 is normal media transport
                             //  Stream 1 is control
    AM_MEDIA_TYPE *pMediaType; // Copy of media type - INVALID after Release()
    BYTE    *pbBuffer;       //  Pointer to buffer - INVALID after Release()
    LONG     cbBuffer;       //  Length of buffer
} AM_SAMPLE2_PROPERTIES;

//=====================================================================
//=====================================================================
// Defines IMediaSample2 interface
//=====================================================================
//=====================================================================

[
        local,
        object,
        uuid(36b73884-c2c8-11cf-8b46-00805f6cef60),
        pointer_default(unique)
]
interface IMediaSample2 : IMediaSample {

    //  Get sample properties
    //
    //      cbProperties - length of generic data to retrieve
    //      pbProperties - pointer to generic data buffer - can
    //                     be NULL if cbProperties is NULL
    //                     data conforms to AM_SAMPLE_PROPERTIES
    //
    HRESULT GetProperties(
        [in] DWORD cbProperties,
        [out, size_is(cbProperties)] BYTE * pbProperties
    );
    //  Set sample properties
    //
    //      cbProperties - length of generic data to set
    //      pbProperties - pointer to generic data buffer - can
    //                      be NULL if cbProperties is NULL
    //                      data conforms to AM_SAMPLE_PROPERTIES
    //
    //
    HRESULT SetProperties(
        [in] DWORD cbProperties,
        [in, size_is(cbProperties)] const BYTE * pbProperties
    );


    // //  Get the clock associated with the sample
    // HRESULT GetClock(
    //     [out] IReferenceClock2 **ppClock
    // );

    // //  Get a pointer to the object containing the data
    // //
    // //  riid      - IID of interface required on object
    // //  ppvobject - Pointer to object containing the data
    // //
    // //  Returns
    // //      S_OK - Got the object
    // //      E_NOINTERFACE - object does not support this interface
    // //                      if IUnknown is not supported
    // //                      there is no backing object
    // //      E_NOTIMPL     - samples don't have backing objects
    // //
    // //
    // HRESULT GetBackingObject(
    //     [in]  REFIID riid,
    //     [out] void **ppvObject
    // );
}

typedef IMediaSample2 *PMEDIASAMPLE2;


// flags for dwFlags in IMemAllocator::GetBuffer
// AM_GBF_PREVFRAMESKIPPED is only significant when asking for a buffer from the
// video renderer.  It should be TRUE if and only if the previous frame
// was skipped.  It affects quality management.
// AM_GBF_NOTASYNCPOINT indicates to the downstream filter (most likely the
// video renderer) that you are not going to fill this buffer with a sync point
// (keyframe) so now would be a bad time to return a buffer with a dynamic
// format change, because you will be unable to switch to the new format without
// waiting for the next sync point, causing some frames to be dropped.
#define AM_GBF_PREVFRAMESKIPPED 1
#define AM_GBF_NOTASYNCPOINT    2
cpp_quote("#define AM_GBF_PREVFRAMESKIPPED 1")
cpp_quote("#define AM_GBF_NOTASYNCPOINT 2")

// This may not be supported by allocators
cpp_quote("#define AM_GBF_NOWAIT 4")