is_EnableEvent

USB 2.0

USB 3.0

GigE

USB 2.0

USB 3.0

GigE

Syntax

INT is_EnableEvent (HIDS hCam, INT which)

Description

Using is_EnableEvent(), you release an event object. Following the release, the event messages for the created event object are enabled. Depending on the operating system different functions are to call.

Windows

•Event has to be provided by the application program

•Event has to be declared by is_InitEvent()

•Event has to be activated by is_EnableEvent()

•You have to wait for the event in the application program by WaitForSingleObject or WaitForMultipleObject

•Event has to be deactivated by is_DisableEvent()

•Event has to be logged off by is_ExitEvent()

Linux

•Event has to be provided by the uEye API

•Event has to be activated by is_EnableEvent()

•You have to wait for the event by is_WaitEvent()

•Event has to be deactivated by is_DisableEvent()

Event handling for images

If you use the event handling to signal new images from the camera, it may occur under high system load that the event-based application does not receive a signal for every image. This is because the event concept does not provide that several events of the same type are stored. If due to system load more than one image is signaled before the application is ready (e.g. WaitForSingleObject), you have no option to capture these missed events.

Input parameters

hCam

Camera handle

ID of the event to be released.

IS_SET_EVENT_AUTOBRIGHTNESS_FINISHED	The automatic brightness control in the run-once mode is completed.
IS_SET_EVENT_AUTOFOCUS_FINISHED	Automatic focus control is finished (see is_Focus()).
IS_SET_EVENT_CAMERA_MEMORY	In the camera memory mode an image acquisition iteration is finished.
IS_SET_EVENT_CAPTURE_STATUS	There is an information about image capturing available. This information can be requested by is_CaptureStatus(). Note that this event replaces the former IS_SET_EVENT_TRANSFER_FAILED from previous versions.
IS_SET_EVENT_CONNECTIONSPEED_CHANGED	The connection speed of a USB 3 uEye camera changed from USB 2.0 to USB 3.0 or from USB 3.0 to USB 2.0.
IS_SET_EVENT_DEVICE_PLUGGED_IN	An already paired GigE uEye camera was reconnected to the network (Requirement: the camera is operated in trusted pairing mode, see is_Configuration()).
IS_SET_EVENT_DEVICE_UNPLUGGED	A paired GigE uEye camera was disconnected from the network (Requirement: the camera is operated in trusted pairing mode, see is_Configuration()).
IS_SET_EVENT_DEVICE_RECONNECTED	A camera initialized with is_InitCamera() and disconnected afterwards was reconnected.
IS_SET_EVENT_EXTTRIG	An image which was captured following the arrival of a trigger has been transferred completely. This is the earliest possible moment for a new capturing process. The image must then be post-processed by the driver and will be available after the IS_FRAME processing event.
IS_SET_EVENT_FIRST_PACKET_RECEIVED	The first data packet of the image was transferred to the PC. This is the earliest time for determining if the image exposure is finished.
IS_SET_EVENT_FRAME	A new image is available.
IS_SET_EVENT_FRAME_RECEIVED	This event is signaled when a new image has arrived in the API before the post-processing is performed.
IS_SET_EVENT_NEW_DEVICE	A new camera was connected. This is independent of the device handle (hCam is ignored).
IS_SET_EVENT_OVERLAY_DATA_LOST	Direct3D/OpenGL mode: Because of a re-programming the parameters of the overlay are invalid. The overlay must be draw new.
IS_SET_EVENT_PMC_IMAGE_PARAMS_CHANGED	Multicast mode: The master has changed camera parameters which affect the data format like image size or color format. The client must reconfigure the virtual camera.
IS_SET_EVENT_REMOVAL	A camera was removed. This is independent of the device handle (hCam is ignored).
IS_SET_EVENT_REMOVE	A camera initialized with is_InitCamera() was disconnected.
IS_SET_EVENT_SEQ	The sequence is completed.
IS_SET_EVENT_STATUS_CHANGED	Linux only: The availability of a camera has changed, e.g. an available camera was opened.
IS_SET_EVENT_STEAL	An image extracted from the overlay is available.
IS_SET_EVENT_TEMPERATURE_STATUS	USB 3 uEye CP Rev. 2/GigE uEye CP Rev. 2/GigE uEye FA/GigE uEye SE Rev. 4 only: The temperature state of the camera has changed, see Querying the temperature state
IS_SET_EVENT_WB_FINISHED	The automatic white balance control is completed.

Return values

IS_INVALID_CAMERA_HANDLE	Invalid camera handle
IS_INVALID_PARAMETER	One of the submitted parameters is outside the valid range or is not supported for this sensor or is not available in this mode.
IS_NO_SUCCESS	General error message
IS_SUCCESS	Function executed successfully

Related functions

•is_DisableEvent()

•Windows only: is_InitEvent()

•Windows only: is_ExitEvent()

•Linux only: is_WaitEvent()

Example Window

HANDLE hEvent = CreateEvent(NULL, FALSE, FALSE, NULL);

is_InitEvent(hCam, hEvent, IS_SET_EVENT_FRAME);

is_EnableEvent(hCam, IS_SET_EVENT_FRAME);

is_FreezeVideo(hCam, IS_DONT_WAIT);

DWORD dwRet = WaitForSingleObject(hEvent, 1000);

if (dwRet == WAIT_TIMEOUT)

{

/* wait timed out */

}

else if (dwRet == WAIT_OBJECT_0)

{

/* event signaled */

}

is_DisableEvent(hCam, IS_SET_EVENT_FRAME);

is_ExitEvent(hCam, IS_SET_EVENT_FRAME);

CloseHandle(hEvent);

Example Linux

is_EnableEvent(hCam, IS_SET_EVENT_FRAME);

is_FreezeVideo(hCam, IS_DONT_WAIT);

INT nRet = is_WaitEvent(hCam, IS_SET_EVENT_FRAME, 1000);

if (nRet == IS_TIMED_OUT)

{

/* wait timed out */

}

else if (nRet == IS_SUCCESS)

{

/* event signaled */

}

is_DisableEvent(hCam, IS_SET_EVENT_FRAME);

Sample programs

•SimpleLive (C++)

•uEyeEvent (C++)

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