C++ (Cpp) PowerSetRequest Examples

Example #1

File: PowerSchemes.cpp Project: ruanzx/PSMJ

/// <summary>
/// Applies the custom power plan.
/// </summary>
/// <returns></returns>
BOOL PowerSchemes::ApplyCustomPowerPlan()
{
	BOOL bSuccess = TRUE;

	/************************************************************************/
	/* Create power request                                                 */
	/************************************************************************/   
	powerReasonContext = new REASON_CONTEXT;
	powerReasonContext->Version = POWER_REQUEST_CONTEXT_VERSION;
	powerReasonContext->Flags = POWER_REQUEST_CONTEXT_SIMPLE_STRING; // POWER_REQUEST_CONTEXT_DETAILED_STRING
	powerReasonContext->Reason.SimpleReasonString = L"Power capping for SMJ";

	hPowerRequest = PowerCreateRequest(powerReasonContext);

	// The calling process continues to run instead of being suspended or terminated 
	// by process lifetime management mechanisms. When and how long the process 
	// is allowed to run depends on the operating system and power policy settings.
	//
	// Value: 
	//  PowerRequestDisplayRequired   : The display remains on even if there is no user input for an extended period of time
	//  PowerRequestSystemRequired    : The system continues to run instead of entering sleep after a period of user inactivity
	//  PowerRequestAwayModeRequired  : Continues to run but turns off audio and video to give the appearance of sleep
	//  PowerRequestExecutionRequired : (win 8 or later)The calling process continues to run 
	//                                  instead of being suspended or terminated by process 
	//                                  lifetime management mechanisms
	if(!PowerSetRequest(hPowerRequest, PowerRequestSystemRequired)) 
	{
		//printf("PowerSetRequest failed\n"); 
	}

	DWORD mySchemeIndex;
	*mySchemeGuid = GUID_POWER_AWARE_SMJ;
	if( !IsPowerSchemeExist(*mySchemeGuid, mySchemeIndex))
	{
		/* Not exist */
		bSuccess&=CreateCustomPowerPlan();
	} 

	/************************************************************************/
	/*  Apply new power scheme                                              */
	/************************************************************************/
	bSuccess&=ApplyPowerScheme(*mySchemeGuid);

	bSuccess&=GetCurrentPowerSettings(); 

	return bSuccess;
}

Example #2

File: Capture.cpp Project: 9578577/Windows-classic-samples

HRESULT CaptureManager::StartPreview()
{
    if (m_pEngine == NULL)
    {
        return MF_E_NOT_INITIALIZED;
    }

    if (m_bPreviewing == true)
    {
        return S_OK;
    }

    IMFCaptureSink *pSink = NULL;
    IMFMediaType *pMediaType = NULL;
    IMFMediaType *pMediaType2 = NULL;
    IMFCaptureSource *pSource = NULL;

    HRESULT hr = S_OK;
    
    // Get a pointer to the preview sink.
    if (m_pPreview == NULL)
    {
        hr = m_pEngine->GetSink(MF_CAPTURE_ENGINE_SINK_TYPE_PREVIEW, &pSink);
        if (FAILED(hr))
        {
            goto done;
        }

        hr = pSink->QueryInterface(IID_PPV_ARGS(&m_pPreview));
        if (FAILED(hr))
        {
            goto done;
        }

        hr = m_pPreview->SetRenderHandle(m_hwndPreview);
        if (FAILED(hr))
        {
            goto done;
        }

        hr = m_pEngine->GetSource(&pSource);
        if (FAILED(hr))
        {
            goto done;
        }

        // Configure the video format for the preview sink.
        hr = pSource->GetCurrentDeviceMediaType((DWORD)MF_CAPTURE_ENGINE_PREFERRED_SOURCE_STREAM_FOR_VIDEO_PREVIEW , &pMediaType);
        if (FAILED(hr))
        {
            goto done;
        }

        hr = CloneVideoMediaType(pMediaType, MFVideoFormat_RGB32, &pMediaType2);
        if (FAILED(hr))
        {
            goto done;
        }

        hr = pMediaType2->SetUINT32(MF_MT_ALL_SAMPLES_INDEPENDENT, TRUE);
        if (FAILED(hr))
        {
            goto done;
        }

        // Connect the video stream to the preview sink.
        DWORD dwSinkStreamIndex;
        hr = m_pPreview->AddStream((DWORD)MF_CAPTURE_ENGINE_PREFERRED_SOURCE_STREAM_FOR_VIDEO_PREVIEW,  pMediaType2, NULL, &dwSinkStreamIndex);        
        if (FAILED(hr))
        {
            goto done;
        }
    }


    hr = m_pEngine->StartPreview();
    if (!m_fPowerRequestSet && m_hpwrRequest != INVALID_HANDLE_VALUE)
    {
        // NOTE:  By calling this, on SOC systems (AOAC enabled), we're asking the system to not go
        // into sleep/connected standby while we're streaming.  However, since we don't want to block
        // the device from ever entering connected standby/sleep, we're going to latch ourselves to
        // the monitor on/off notification (RegisterPowerSettingNotification(GUID_MONITOR_POWER_ON)).
        // On SOC systems, this notification will fire when the user decides to put the device in
        // connected standby mode--we can trap this, turn off our media streams and clear this
        // power set request to allow the device to go into the lower power state.
        m_fPowerRequestSet = (TRUE == PowerSetRequest(m_hpwrRequest, PowerRequestExecutionRequired));
    }
done:
    SafeRelease(&pSink);
    SafeRelease(&pMediaType);
    SafeRelease(&pMediaType2);
    SafeRelease(&pSource);

    return hr;
}