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// ----------------------------------------------------------------------
// Our static function for finding num devices available etc
// 摘自cap_dshow.cpp 文件
// ----------------------------------------------------------------------

int videoInput::listDevices(bool silent){

    //COM Library Intialization
    comInit();

    if(!silent)printf("\nVIDEOINPUT SPY MODE!\n\n");


    ICreateDevEnum *pDevEnum = NULL;
    IEnumMoniker *pEnum = NULL;
    int deviceCounter = 0;

    HRESULT hr = CoCreateInstance(CLSID_SystemDeviceEnum, NULL,
        CLSCTX_INPROC_SERVER, IID_ICreateDevEnum,
        reinterpret_cast(&pDevEnum));


    if (SUCCEEDED(hr))
    {
        // Create an enumerator for the video capture category.
        hr = pDevEnum->CreateClassEnumerator(
            CLSID_VideoInputDeviceCategory,
            &pEnum, 0);

       if(hr == S_OK){

             if(!silent)printf("SETUP: Looking For Capture Devices\n");
            IMoniker *pMoniker = NULL;

            while (pEnum->Next(1, &pMoniker, NULL) == S_OK){

                IPropertyBag *pPropBag;
                hr = pMoniker->BindToStorage(0, 0, IID_IPropertyBag,
                    (void**)(&pPropBag));

                if (FAILED(hr)){
                    pMoniker->Release();
                    continue;  // Skip this one, maybe the next one will work.
                }


                 // Find the description or friendly name.
                VARIANT varName;
                VariantInit(&varName);
                hr = pPropBag->Read(L"Description", &varName, 0);

                if (FAILED(hr)) hr = pPropBag->Read(L"FriendlyName", &varName, 0);

                if (SUCCEEDED(hr)){

                    hr = pPropBag->Read(L"FriendlyName", &varName, 0);

                    int count = 0;
                    int maxLen = sizeof(deviceNames[0])/sizeof(deviceNames[0][0]) - 2;
                    while( varName.bstrVal[count] != 0x00 && count < maxLen) {
                        deviceNames[deviceCounter][count] = (char)varName.bstrVal[count];
                        count++;
                    }
                    deviceNames[deviceCounter][count] = 0;

                    if(!silent)printf("SETUP: %i) %s \n",deviceCounter, deviceNames[deviceCounter]);
                }

                pPropBag->Release();
                pPropBag = NULL;

                pMoniker->Release();
                pMoniker = NULL;

                deviceCounter++;
            }

            pDevEnum->Release();
            pDevEnum = NULL;

            pEnum->Release();
            pEnum = NULL;
        }

         if(!silent)printf("SETUP: %i Device(s) found\n\n", deviceCounter);
    }

    comUnInit();

    return deviceCounter;
}