INotify

Interface for being notified when a driver event happened. More...

Typedefs
typedef void __stdcall *	CVBDRIVER_NOTIFY_CB(CVNotifyEvent_t EventID, void *Buf, size_t Size, CVNotifyDatatype_t DataType, void *UserData)
	Callback function which is called with INotify related events. This function can be registered by the NORegister function to get notifications. More...
typedef cvbval_t	CVNotifyDatatype_t
	Defines the datatype for the INotify data. See CVNotifyDatatypes for possible types. More...
typedef cvbval_t	CVNotifyEvent_t
	Defines the data type/IDs for the INotify events. See CVNotifyEventIDs for possible types. More...
typedef cvbval_t	CVNotifyInfo_t
	Defines the data type for the INotify information. See CVNotifyInfoCmd for possible information commands. More...

Enumerations
enum	CVNotifyDatatypes {   CVNO_DATA_VOID = -1 , CVNO_DATA_INTEGER64 = 0 , CVNO_DATA_FLOAT64 , CVNO_DATA_STRING ,   CVNO_DATA_BINARY , CVNO_DATA_BOOL8 , CVNO_DATA_CUSTOM = 0x10000 }
	Defines the Notify data types. More...
enum	CVNotifyEventIDs {   CVNO_REGISTRATION_INVALID = 0 , CVNO_EID_ERROR = 1 , CVNO_EID_DEVICE_DISCONNECTED = 2 , CVNO_EID_DEVICE_RECONNECT = 3 ,   CVNO_EID_GEOMETRY_CHANGE = 4 , CVNO_EID_METADATA_CHANGE = 5 , CVNO_EID_CUSTOM = 0x10000 }
	An EventID references a single event source. It is a number. The numbers below 0x1000 have a globally defined meaning. The numbers above are driver implementation private and may have other meanings with other sources. More...
enum	CVNotifyInfoCmd { CVNO_INFO_COUNT_REGISTERED , CVNO_INFO_COUNT_FIRED , CVNO_INFO_IS_AVAILABLE , NO_INFO_CUSTOM_CMD = 0x10000 }
	Defines the command for getting an information from the Notify interface. More...

Functions
cvbbool_t	CanNotify (IMG Image)
	This function verifies whether the image supports the INotify interface. More...
cvbres_t	NOGetDescription (IMG Image, size_t Index, char *DescriptiveName, size_t &Size, CVNotifyEvent_t &EventID)
	Inquire a readable description (name) and the event ID for a given Index. More...
cvbres_t	NOGetNumSupported (IMG Image, size_t &NumEvents)
	Iniquire the number of supported event sources. More...
cvbres_t	NOGetStatus (IMG Image, CVNotifyEvent_t eventID, CVNotifyInfo_t StatusCmd, cvbint64_t &Info)
	Inquire additional information on an event source. More...
cvbres_t	NOIsCookieValid (IMG Image, intptr_t Cookie, cvbbool_t &IsValid)
	Inquire if a given Cookie is still referring to a registered callback. More...
cvbres_t	NORegister (IMG Image, CVNotifyEvent_t EventID, CVBDRIVER_NOTIFY_CB pCB, void *UserData, intptr_t &Cookie)
	Register a callback for one (or more) events. More...
cvbres_t	NOUnregister (IMG Image, intptr_t Cookie)
	Unregister a callback. More...

Detailed Description

Interface for being notified when a driver event happened.

Typedef Documentation

CVBDRIVER_NOTIFY_CB

typedef void __stdcall * CVBDRIVER_NOTIFY_CB(CVNotifyEvent_t EventID, void *Buf, size_t Size, CVNotifyDatatype_t DataType, void *UserData)

Callback function which is called with INotify related events.

This function can be registered by the NORegister function to get notifications.

Attention

The list below descripes the specific constant declarations and typedefs. There are declared in the header file iCVCDriver.h .

Parameters

[in]	EventID	ID identifying a single event source.
[in]	Buf	Databuffer associated with that event.
[in]	Size	Size of Buf in bytes.
[in]	DataType	Datatype (see CVNotifyDatatype_t for more information).
[in]	UserData	Pointer to private data provided at callback registration with NORegister.

Supported platforms:

Win32
Win64
Linux

Examples:

Visual C++ - VC Movie2 Player Example CSharp - C# Movie2 Player Example

Sample Code in Visual C++:

void CVCMovie2PlayerExampleDlg::ImageUpdatedCvimagectrl1()
{
  if(CanNotify((IMG)m_cvImg.GetImage()))
  {
    // Check If MetaData is available in the video file. If yes Register the MetaDataAvailable callback
    // If no Output message in StatusUserText.
    __int64 info;
    HRESULT res = NOGetStatus((IMG)m_cvImg.GetImage(),
                               CVNO_EID_METADATA_CHANGE,
                               CVNO_INFO_IS_AVAILABLE,
                               info);
 
    if(info == 1)
      res = NORegister((IMG)m_cvImg.GetImage(),
                        CVNO_EID_METADATA_CHANGE,
                        &CVCMovie2PlayerExampleDlg::MetaDataAvailable,
                        this,
                        m_MetaDataAvailableCallbackCookie);
    else
      m_cvDisp.SetStatusUserText("No MetaData available");
  }
}
 
void CALLBACK CVCMovie2PlayerExampleDlg::MetaDataAvailable( CVNotifyEvent_t EventID, void *Buf, size_t Size,
CVNotifyDatatype_t DataType, void *UserData)
{
  CVCMovie2PlayerExampleDlg* dlg = reinterpret_cast<CVCMovie2PlayerExampleDlg*>(UserData);
  dlg->m_cvDisp.SetStatusUserText(reinterpret_cast<char*>(Buf));
}

Sample Code in CSharp:

private void m_cvImage_ImageUpdated(object sender, EventArgs e)
{
  if (Cvb.Driver.INotify.CanNotify(m_cvImage.Image))
  {
    // Check If MetaData is available in the video file. If yes Register the MetaDataAvailable callback
    // If no Output message in StatusUserText.
    Cvb.Driver.INotify.NOGetStatus(m_cvImage.Image,
                                   Cvb.Driver.INotify.CVNotifyEventID.METADATA_CHANGE,
                                   Cvb.Driver.INotify.CVNotifyInfoCmd.IS_AVAILABLE,
                                   out info);
    if (info == 1)
      Cvb.Driver.INotify.NORegister(m_cvImage.Image,
                                    Cvb.Driver.INotify.CVNotifyEventID.METADATA_CHANGE,
                                    MetaDataChangedDelegate,
                                    this.Handle,
                                    out m_MetaDataCallbackCookie);
    else
      _MetaDataTextBox.Text = "No MetaData available";
   }
}
 
private delegate void MetaDataDelegate();
public void MetaDataChanged_Event(Cvb.Driver.INotify.CVNotifyEventID eventID,IntPtr buffer,
int Size,Cvb.Driver.INotify.CVNotifyDataType DataType,IntPtr UserData)
{
  if (DataType == Cvb.Driver.INotify.CVNotifyDataType.STRING)
  {
    Form1 mainForm = (Form1)Control.FromHandle(UserData);
    string myString = System.Runtime.InteropServices.Marshal.PtrToStringAnsi(buffer);
 
    // note: the MetaDataChanged Callback is most likely raised in a thread
    // context *different* from the user interface thread and there-
    // fore the user interface should not be influenced directly when
    // processing this event, but rather through BeginInvoke
    this.BeginInvoke(new MetaDataDelegate(delegate()
    {
      // Add Information to the Display UserText
      mainForm._MetaDataTextBox.Text = myString;
    }));
  }
}

CVNotifyDatatype_t

typedef cvbval_t CVNotifyDatatype_t

Defines the datatype for the INotify data. See CVNotifyDatatypes for possible types.

Attention

The list below descripes the specific constant declarations and typedefs. There are declared in the header file iCVCDriver.* .

CVNotifyEvent_t

typedef cvbval_t CVNotifyEvent_t

Defines the data type/IDs for the INotify events. See CVNotifyEventIDs for possible types.

Attention

The list below descripes the specific constant declarations and typedefs. There are declared in the header file iCVCDriver.* .

CVNotifyInfo_t

typedef cvbval_t CVNotifyInfo_t

Defines the data type for the INotify information. See CVNotifyInfoCmd for possible information commands.

Attention

The list below descripes the specific constant declarations and typedefs. There are declared in the header file iCVCDriver.* .

Enumeration Type Documentation

CVNotifyDatatypes

enum CVNotifyDatatypes

Defines the Notify data types.

Attention

The list below descripes the specific constant declarations and typedefs. There are declared in the header file iCVCDriver.* .

Enumerator
CVNO_DATA_VOID	Void data.
CVNO_DATA_INTEGER64	64-bit integer.
CVNO_DATA_FLOAT64	64-bit floating-point value.
CVNO_DATA_STRING	String value.
CVNO_DATA_BINARY	Binary data.
CVNO_DATA_BOOL8	8-bit bool data.
CVNO_DATA_CUSTOM	Custom data.

CVNotifyEventIDs

enum CVNotifyEventIDs

An EventID references a single event source.

It is a number. The numbers below 0x1000 have a globally defined meaning. The numbers above are driver implementation private and may have other meanings with other sources.

Attention

The list below descripes the specific constant declarations and typedefs. There are declared in the header file iCVCDriver.* .

Enumerator
CVNO_REGISTRATION_INVALID	The registered callback is no longer registered (e.g. after device switch).
CVNO_EID_ERROR	General Error. A description may be provided as string in the provided buffer in the callback.
CVNO_EID_DEVICE_DISCONNECTED	Camera disconnect.
CVNO_EID_DEVICE_RECONNECT	Camera reconnect.
CVNO_EID_GEOMETRY_CHANGE	The image geometry/data type has been changed (e.g. IRImageRect or port switch).
CVNO_EID_METADATA_CHANGE	New metadata available. The metadata is provided as string int the provided buffer of the callback.
CVNO_EID_CUSTOM	Custom event id.

CVNotifyInfoCmd

enum CVNotifyInfoCmd

Defines the command for getting an information from the Notify interface.

Attention

The list below descripes the specific constant declarations and typedefs. There are declared in the header file iCVCDriver.* .

Enumerator
CVNO_INFO_COUNT_REGISTERED	Number of callbacks registered.
CVNO_INFO_COUNT_FIRED	Number of callbacks fired for a specific data type.
CVNO_INFO_IS_AVAILABLE	Availability of the event at the time of the status inquiry.
NO_INFO_CUSTOM_CMD	Custom information.

Function Documentation

CanNotify()

cvbbool_t CanNotify

(

IMG

Image

)

This function verifies whether the image supports the INotify interface.

Parameters

[in]

Image

Handle of image object.

Returns

TRUE if the image supports the Notify interface, FALSE otherwise.

Supported platforms:

Win32
Win64
Linux

NOGetDescription()

cvbres_t NOGetDescription	(	IMG	Image,
		size_t	Index,
		char *	DescriptiveName,
		size_t &	Size,
		CVNotifyEvent_t &	EventID
	)

Inquire a readable description (name) and the event ID for a given Index.

This ID is used to register/unregister an event.

Parameters

[in]	Image	Handle of image object.
[in]	Index	Index for the supported notify events list. The range is from 0 to NotifyEventCount 1 (see NOGetStatus).
[in,out]	DescriptiveName	Gets the human readable event name for the given index.
[in,out]	Size	Size of Buffer in bytes.
[out]	EventID	Unique number identifying a single source of events (see CVNotifyEvent_t)

Returns

>=0 : OK
<0 : an error occured

Supported platforms:

Win32
Win64
Linux

Related Topics:

NORegister
NOUnregister

NOGetNumSupported()

cvbres_t NOGetNumSupported	(	IMG	Image,
		size_t &	NumEvents
	)

Iniquire the number of supported event sources.

Attention

The number of supported events must not change at runtime. If an event is not supported at a given time this can be inquired through the status.

Parameters

[in]	Image	Handle of image object.
[out]	NumEvents	Number of supported event sources.

Returns

>=0 : OK
<0 : an error occured

Supported platforms:

Win32
Win64
Linux

NOGetStatus()

cvbres_t NOGetStatus	(	IMG	Image,
		CVNotifyEvent_t	eventID,
		CVNotifyInfo_t	StatusCmd,
		cvbint64_t &	Info
	)

Inquire additional information on an event source.

For example: Number of callbacks registered or number of times fired Availability at a certain time.

Parameters

[in]	Image	Handle of image object.
[in]	eventID	Unique number identifying a single source of events. If a 0 is passed as argument the callback will receive ALL events from a driver instance (see CVNotifyEvent_t).
[in]	StatusCmd	Possible command to execute like CVNO_INFO_COUNT_REGISTERED (see CVNotifyInfo_t for more information).
[out]	Info	A number referencing a certain information related to an EventID.

Returns

>=0 : OK
<0 : an error occured

Supported platforms:

Win32
Win64
Linux

Related Topics:

NORegister
NOUnregister

NOIsCookieValid()

cvbres_t NOIsCookieValid	(	IMG	Image,
		intptr_t	Cookie,
		cvbbool_t &	IsValid
	)

Inquire if a given Cookie is still referring to a registered callback.

Parameters

[in]	Image	Handle of image object.
[in]	Cookie	Is a unique handle referencing a single callback registration.
[out]	IsValid	TRUE, if cookie is valid, FALSE otherwise.

Returns

>=0 : OK
<0 : an error occured

Supported platforms:

Win32
Win64
Linux

NORegister()

cvbres_t NORegister	(	IMG	Image,
		CVNotifyEvent_t	EventID,
		CVBDRIVER_NOTIFY_CB	pCB,
		void *	UserData,
		intptr_t &	Cookie
	)

Register a callback for one (or more) events.

The callback stays registered until either the driver is unloaded, the NOUnregister function is called or the CVNO_REGISTRATION_INVALID (see CVNotifyEventIDs) is fired. With a driver unload the callback is unregistered automatically. After a reload of the driver the callback has to be registered again.

Parameters

[in]	Image	Handle of image object.
[in]	EventID	Unique number identifying a single source of events. If a 0 is passed as argument the callback will receive ALL events from a driver instance (see CVNotifyEvent_t).
[in]	pCB	Callback function (see CVBDRIVER_NOTIFY_CB)
[in]	UserData	User provided pointer to private data which gets passed to the event callback function.
[out]	Cookie	Cookie referencing a single callback registration. This cookie must be used to unregister the callback. The cookie might change from session to session.

Returns

>=0 : OK
<0 : an error occured

Supported platforms:

Win32
Win64
Linux

Related Topics:

NOUnregister

NOUnregister()

cvbres_t NOUnregister	(	IMG	Image,
		intptr_t	Cookie
	)

Unregister a callback.

In case of a driver unload this unregister is done automatically.

Parameters

[in]	Image	Handle of image object.
[in]	Cookie	Is a unique handle referencing a single callback registration.

Returns

>=0 : OK
<0 : an error occured

Supported platforms:

Win32
Win64
Linux

Related Topics:

NORegister