Modify the Grabber filter to work with Sample Grabber

I modified the grabber Directshow filter in MSDN sample.

This grabber is used in our WMINTF application.

The modification is as follows :

typedef HRESULT (*SAMPLECALLBACK) (
IMediaSample * pSample,
REFERENCE_TIME * StartTime,
REFERENCE_TIME * StopTime,
BOOL TypeChanged);

the above code is changed as follows :

typedef HRESULT (*SAMPLECALLBACK) (
IMediaSample * pSample,
REFERENCE_TIME * StartTime,
REFERENCE_TIME * StopTime,
BOOL TypeChanged,
void* pInstanceData);


MIDL_INTERFACE("6B652FFF-11FE-4FCE-92AD-0266B5D7C78F")
IGrabberSample : public IUnknown
{

public:



virtual HRESULT STDMETHODCALLTYPE SetCallback(
SAMPLECALLBACK Callback) = 0;// this code is changed as follows :


virtual HRESULT STDMETHODCALLTYPE SetCallback(
SAMPLECALLBACK Callback,void* pInstanceData) = 0;

}



class CSampleGrabber: public IGrabberSample
{
public:

HRESULT STDMETHODCALLTYPE SetCallback(
SAMPLECALLBACK Callback) = 0;// this code is changed as follows :

HRESULT STDMETHODCALLTYPE SetCallback(
SAMPLECALLBACK Callback,void* pInstanceData) = 0;
private:

// Newly added code...
void* m_pInstanceData;
};


SetCallback(SAMPLECALLBACK Callback,void* pInstanceData)
{
m_Callback = Callback;
m_pInstanceData = pInstanceData; //Newly added code
}

within the Grabber filter,

m_Callback( ) fn is called as follows :


HRESULT hr = m_callback( pms, &StartTime, &StopTime, *pTypeChanged); //I modified this code as follows :

HRESULT hr = m_callback( pms, &StartTime, &StopTime, *pTypeChanged,m_pInstanceData);

Afterwards I compiled the Grabber filter.

and copied the following code (Client's)grabber.h as follows:The user class argument is used...

Client must aware of the interface IGrabberSample .

This is done thru the client's grabber.h file.


class CGraph;
typedef HRESULT (CGraph::*SAMPLECALLBACK) (
IMediaSample * pSample,
REFERENCE_TIME * StartTime,
REFERENCE_TIME * StopTime,
BOOL TypeChanged,
void *pInstanceData);


// We define the interface the app can use to program us
MIDL_INTERFACE("6B652FFF-11FE-4FCE-92AD-0266B5D7C78F")
IGrabberSample : public IUnknown
{
public:

virtual HRESULT STDMETHODCALLTYPE SetAcceptedMediaType(
const AM_MEDIA_TYPE *pType) = 0;

virtual HRESULT STDMETHODCALLTYPE GetConnectedMediaType(
AM_MEDIA_TYPE *pType) = 0;

virtual HRESULT STDMETHODCALLTYPE SetCallback(
SAMPLECALLBACK Callback,void* pInstanceData) = 0;

virtual HRESULT STDMETHODCALLTYPE SetDeliveryBuffer(
ALLOCATOR_PROPERTIES props,
BYTE *pBuffer) = 0;
};