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DirectShow Source Filter that reads data from application

Mentioned below is an example of a DirectShow source filter that reads data from application

For reference I have taken CPushSource filter from DirectShow samples

Include the code mentioned below in a common header file


DECLARE_INTERFACE_(IMySettingsInterface, IUnknown)
{

STDMETHOD(GetParamInt)(char* szName, int *pParam) = 0;
STDMETHOD(SetParamInt)(char* szName, int nParam) = 0;

};

// {F350FE9E-65BA-4AC1-A6C0-FD9F2979D342}


DEFINE_GUID(IID_IMySettings,

0xf350fe9e, 0x65ba, 0x4ac1, 0xa6, 0xc0, 0xfd, 0x9f, 0x29, 0x79, 0xd3, 0x42);

Change made to CPushSourceDesktop class:

class CPushSourceDesktop : public CSource, public IMySettingsInterface

{

private:

// Constructor is private because you have to use CreateInstance

CPushSourceDesktop(IUnknown *pUnk, HRESULT *phr);

~CPushSourceDesktop();

CPushPinDesktop *m_pPin;

public:

DECLARE_IUNKNOWN;

static CUnknown * WINAPI CreateInstance(IUnknown *pUnk, HRESULT *phr);  

STDMETHODIMP NonDelegatingQueryInterface(REFIID riid, void **ppv);

//Methods the interface supports

STDMETHODIMP GetParamInt(char* szName, int *pParam);

STDMETHODIMP SetParamInt(char* szName, int nParam);

};

Defined these interface methods in my filter

STDMETHODIMP CPushSourceDesktop::NonDelegatingQueryInterface(REFIID riid, void **ppv)
{
    if (riid == (IID_IMySettings))
    {
        return GetInterface((IMySettingsInterface*) this, ppv);
    }
    else
    {
        return CSource::NonDelegatingQueryInterface(riid, ppv);
    }
}


STDMETHODIMP CPushSourceDesktop::GetParamInt(char* szName, int *pParam)

{
    // Example

    *pParam = 10;

    return 0;
}

STDMETHODIMP CPushSourceDesktop::SetParamInt(char* szName, int pParam)
{

    //Example
    return 0;
}


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