Comment implémenter des propriétés de contrôle de caméra étendues

Le pilote de caméra doit implémenter des propriétés de contrôle de caméra étendues en tant que jeux de propriétés individuels, c’est-à-dire que chaque propriété doit être implémentée en tant que jeu de propriétés unique. L’exemple de code suivant peut être utilisé comme point de départ pour implémenter ces propriétés.

Note Étant donné que la taille des données d’une propriété étendue peut être de longueur arbitraire, interrogez la pile en mode utilisateur pour connaître la taille des données en transmettant une mémoire tampon null. Un processus en deux étapes est nécessaire : tout d’abord, le pilote retourne la longueur requise, comme indiqué dans l’exemple de code, puis la pile en mode utilisateur demande une mémoire tampon appropriée pour les données de propriété.

Implémentation du pilote

DEFINE_KSPROPERTY_TABLE(SocSimFilterFocusPropertyItems)
{       
    DEFINE_KSPROPERTY_ITEM(
        0,
        CCaptureFilter::FocusRectHandler,
        sizeof(KSPROPERTY),
        0,
        CCaptureFilter::FocusRectHandler,
        NULL, 0, NULL, NULL, 0
        )
};

DEFINE_KSPROPERTY_TABLE(SocSimFilterVideoStabPropertyItems)
{       
    DEFINE_KSPROPERTY_ITEM(
        0,
        CCaptureFilter::VideoStabilizationModeHandler,
        sizeof(KSPROPERTY),
        0,
        CCaptureFilter::VideoStabilizationModeHandler,
        NULL, 0, NULL, NULL, 0
        )
};

DEFINE_KSPROPERTY_TABLE(SocSimFilterFlashPropertyItems)
{       
    DEFINE_KSPROPERTY_ITEM(
        0,
        CCaptureFilter::FlashHandler,
        sizeof(KSPROPERTY),
        0,
        CCaptureFilter::FlashHandler,
        NULL, 0, NULL, NULL, 0
        )
};

DEFINE_KSPROPERTY_SET_TABLE(SocSimFilterPropertySets)
{
    DEFINE_KSPROPERTY_SET(
        &PROPSETID_VIDCAP_CAMERACONTROL_REGION_OF_INTEREST,
        SIZEOF_ARRAY(SocSimFilterFocusPropertyItems),
        SocSimFilterFocusPropertyItems,
        0,
        NULL),

    DEFINE_KSPROPERTY_SET(
        &PROPSETID_VIDCAP_CAMERACONTROL_FLASH,
        SIZEOF_ARRAY(SocSimFilterFlashPropertyItems),
        SocSimFilterFlashPropertyItems,
        0,
        NULL),

    DEFINE_KSPROPERTY_SET(
        &PROPSETID_VIDCAP_CAMERACONTROL_VIDEO_STABILIZATION,
        SIZEOF_ARRAY(SocSimFilterVideoStabPropertyItems),
        SocSimFilterVideoStabPropertyItems,
        0,
        NULL)

};

NTSTATUS
CCaptureFilter::FlashHandler(
    __in    PIRP Irp,
    __in    PKSPROPERTY Property,
    __inout PVOID pData
    )
{
    PAGED_CODE();
    NTSTATUS Status = STATUS_SUCCESS;
    NT_ASSERT(Irp);
    NT_ASSERT(Property);

    CCaptureFilter* pFilter = reinterpret_cast <CCaptureFilter*>(KsGetFilterFromIrp(Irp)->Context);

    PIO_STACK_LOCATION pIrpStack = IoGetCurrentIrpStackLocation(Irp);
    ULONG ulOutputBufferLength = pIrpStack->Parameters.DeviceIoControl.OutputBufferLength;
    ULONG InputBufferLength = pIrpStack->Parameters.DeviceIoControl.InputBufferLength;

    if (Property->Flags & KSPROPERTY_TYPE_SET)
    {
        if (ulOutputBufferLength == 0)
        {
            Irp->IoStatus.Information = sizeof(KSPROPERTY_CAMERACONTROL_FLASH_S);
            Status = STATUS_BUFFER_OVERFLOW;
        }
        else if (ulOutputBufferLength < sizeof(KSPROPERTY_CAMERACONTROL_FLASH_S))
        {
            Status = STATUS_BUFFER_TOO_SMALL;
        }
        else if (pData && ulOutputBufferLength >= sizeof(KSPROPERTY_CAMERACONTROL_FLASH_S))
        {
            PKSPROPERTY_CAMERACONTROL_FLASH_S pFlash = (PKSPROPERTY_CAMERACONTROL_FLASH_S)pData;
            pFilter->m_Flash = pFlash->Flash;
            pFilter->m_FlashCapabilites = pFlash->Capabilities;
            Status = STATUS_SUCCESS;
            Irp->IoStatus.Information = sizeof(KSPROPERTY_CAMERACONTROL_FLASH_S);
        }
        else 
        {
            Status = STATUS_INVALID_PARAMETER;
        }
    }
    else if (Property->Flags & KSPROPERTY_TYPE_GET)
    {
        if (ulOutputBufferLength == 0)
        {
            Irp->IoStatus.Information = sizeof(KSPROPERTY_CAMERACONTROL_FLASH_S);
            Status = STATUS_BUFFER_OVERFLOW;
        }
        else if (ulOutputBufferLength < sizeof(KSPROPERTY_CAMERACONTROL_FLASH_S))
        {
            Status = STATUS_BUFFER_TOO_SMALL;
        }
        else if (pData && ulOutputBufferLength >= sizeof(KSPROPERTY_CAMERACONTROL_FLASH_S))
        {
            PKSPROPERTY_CAMERACONTROL_FLASH_S pFlash = (PKSPROPERTY_CAMERACONTROL_FLASH_S)pData;
            pFlash->Flash = pFilter->m_Flash;
            pFlash->Capabilities = pFilter->m_FlashCapabilites;
            Irp->IoStatus.Information = sizeof(KSPROPERTY_CAMERACONTROL_FLASH_S);
            Status = STATUS_SUCCESS;
        }
        else
        {
            Status = STATUS_INVALID_PARAMETER;
        }
    }

    return Status;
}

NTSTATUS
CCaptureFilter::VideoStabilizationModeHandler(
    __in    PIRP Irp,
    __in    PKSPROPERTY Property,
    __inout PVOID pData
    )
{
    PAGED_CODE();
    NTSTATUS Status = STATUS_SUCCESS;
    NT_ASSERT(Irp);
    NT_ASSERT(Property);

    CCaptureFilter* pFilter = reinterpret_cast <CCaptureFilter*>(KsGetFilterFromIrp(Irp)->Context);

    PIO_STACK_LOCATION pIrpStack = IoGetCurrentIrpStackLocation(Irp);
    ULONG ulOutputBufferLength = pIrpStack->Parameters.DeviceIoControl.OutputBufferLength;
    ULONG InputBufferLength = pIrpStack->Parameters.DeviceIoControl.InputBufferLength;

    if (Property->Flags & KSPROPERTY_TYPE_SET)
    {
        if (ulOutputBufferLength == 0)
        {
            Irp->IoStatus.Information = sizeof(KSPROPERTY_CAMERACONTROL_VIDEOSTABILIZATION_MODE_S);
            Status = STATUS_BUFFER_OVERFLOW;
        }
        else if (ulOutputBufferLength < sizeof(KSPROPERTY_CAMERACONTROL_VIDEOSTABILIZATION_MODE_S))
        {
            Status = STATUS_BUFFER_TOO_SMALL;
        }
        else if (pData && ulOutputBufferLength >= sizeof(KSPROPERTY_CAMERACONTROL_VIDEOSTABILIZATION_MODE_S))
        {
            PKSPROPERTY_CAMERACONTROL_VIDEOSTABILIZATION_MODE_S pVideoStab = (PKSPROPERTY_CAMERACONTROL_VIDEOSTABILIZATION_MODE_S)pData;
            pFilter->m_VideoStabMode = pVideoStab->VideoStabilizationMode;
            pFilter->m_VideoStabCapabilites = pVideoStab->Capabilities;
            Status = STATUS_SUCCESS;
            Irp->IoStatus.Information = sizeof(KSPROPERTY_CAMERACONTROL_VIDEOSTABILIZATION_MODE_S);
        }
        else 
        {
            Status = STATUS_INVALID_PARAMETER;
        }
    }
    else if (Property->Flags & KSPROPERTY_TYPE_GET)
    {
        if (ulOutputBufferLength == 0)
        {
            Irp->IoStatus.Information = sizeof(KSPROPERTY_CAMERACONTROL_VIDEOSTABILIZATION_MODE_S);
            Status = STATUS_BUFFER_OVERFLOW;
        }
        else if (ulOutputBufferLength < sizeof(KSPROPERTY_CAMERACONTROL_VIDEOSTABILIZATION_MODE_S))
        {
            Status = STATUS_BUFFER_TOO_SMALL;
        }
        else if (pData && ulOutputBufferLength >= sizeof(KSPROPERTY_CAMERACONTROL_VIDEOSTABILIZATION_MODE_S))
        {
            PKSPROPERTY_CAMERACONTROL_VIDEOSTABILIZATION_MODE_S pVideoStab = (PKSPROPERTY_CAMERACONTROL_VIDEOSTABILIZATION_MODE_S)pData;
            pVideoStab->VideoStabilizationMode = pFilter->m_VideoStabMode;
            pVideoStab->Capabilities = pFilter->m_VideoStabCapabilites;
            Irp->IoStatus.Information = sizeof(KSPROPERTY_CAMERACONTROL_VIDEOSTABILIZATION_MODE_S);
            Status = STATUS_SUCCESS;
        }
        else
        {
            Status = STATUS_INVALID_PARAMETER;
        }
    }

    return Status;
}

NTSTATUS
CCaptureFilter::FocusRectHandler(
    __in    PIRP Irp,
    __in    PKSPROPERTY Property,
    __inout PVOID pData
    )
{
    PAGED_CODE();
    NTSTATUS Status = STATUS_SUCCESS;
    NT_ASSERT(Irp);
    NT_ASSERT(Property);

    CCaptureFilter* pFilter = reinterpret_cast <CCaptureFilter*>(KsGetFilterFromIrp(Irp)->Context);

    PIO_STACK_LOCATION pIrpStack = IoGetCurrentIrpStackLocation(Irp);
    ULONG ulOutputBufferLength = pIrpStack->Parameters.DeviceIoControl.OutputBufferLength;
    ULONG InputBufferLength = pIrpStack->Parameters.DeviceIoControl.InputBufferLength;

    if (Property->Flags & KSPROPERTY_TYPE_SET)
    {
        if (ulOutputBufferLength == 0)
        {
            Irp->IoStatus.Information = sizeof(KSPROPERTY_CAMERACONTROL_REGION_OF_INTEREST_S);
            Status = STATUS_BUFFER_OVERFLOW;
        }
        else if (ulOutputBufferLength < sizeof(KSPROPERTY_CAMERACONTROL_REGION_OF_INTEREST_S))
        {
            Status = STATUS_BUFFER_TOO_SMALL;
        }
        else if (pData && ulOutputBufferLength >= sizeof(KSPROPERTY_CAMERACONTROL_REGION_OF_INTEREST_S))
        {
            PKSPROPERTY_CAMERACONTROL_REGION_OF_INTEREST_S pFocusRect = (PKSPROPERTY_CAMERACONTROL_REGION_OF_INTEREST_S)pData;
            pFilter->m_FocusRect.left = pFocusRect->FocusRect.left;
            pFilter->m_FocusRect.top = pFocusRect->FocusRect.top;
            pFilter->m_FocusRect.right = pFocusRect->FocusRect.right;
            pFilter->m_FocusRect.bottom = pFocusRect->FocusRect.bottom;
            pFilter->m_AutoFocusLock = pFocusRect->AutoFocusLock;
            pFilter->m_AutoExposureLock = pFocusRect->AutoExposureLock;
            pFilter->m_AutoWhitebalanceLock = pFocusRect->AutoWhitebalanceLock;
            Status = STATUS_SUCCESS;
            Irp->IoStatus.Information = sizeof(KSPROPERTY_CAMERACONTROL_REGION_OF_INTEREST_S);
        }
        else 
        {
            Status = STATUS_INVALID_PARAMETER;
        }
    }
    else if (Property->Flags & KSPROPERTY_TYPE_GET)
    {
        if (ulOutputBufferLength == 0)
        {
            Irp->IoStatus.Information = sizeof(KSPROPERTY_CAMERACONTROL_REGION_OF_INTEREST_S);
            Status = STATUS_BUFFER_OVERFLOW;
        }
        else if (ulOutputBufferLength < sizeof(KSPROPERTY_CAMERACONTROL_REGION_OF_INTEREST_S))
        {
            Status = STATUS_BUFFER_TOO_SMALL;
        }
        else if (pData && ulOutputBufferLength >= sizeof(KSPROPERTY_CAMERACONTROL_REGION_OF_INTEREST_S))
        {
            PKSPROPERTY_CAMERACONTROL_REGION_OF_INTEREST_S pFocusRect = (PKSPROPERTY_CAMERACONTROL_REGION_OF_INTEREST_S)pData;
            pFocusRect->FocusRect.left = pFilter->m_FocusRect.left;
            pFocusRect->FocusRect.top = pFilter->m_FocusRect.top;
            pFocusRect->FocusRect.right = pFilter->m_FocusRect.right;
            pFocusRect->FocusRect.bottom = pFilter->m_FocusRect.bottom;
            pFocusRect->AutoFocusLock = pFilter->m_AutoFocusLock;
            pFocusRect->AutoExposureLock = pFilter->m_AutoExposureLock;
            pFocusRect->AutoWhitebalanceLock = pFilter->m_AutoWhitebalanceLock;
            Irp->IoStatus.Information = sizeof(KSPROPERTY_CAMERACONTROL_REGION_OF_INTEREST_S);
            Status = STATUS_SUCCESS;
        }
        else
        {
            Status = STATUS_INVALID_PARAMETER;
        }
    }

    return Status;
}