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Event / Message Handling

uEye Camera Manual Version 3.80

Event / Message Handling

Triggering Events for Single-Frame Capture

The following figure shows the time sequence when triggering the IS_TRIGGER and IS_FRAME events. The camera is prepared for triggered capture using the is_SetExternalTrigger() command. An incoming trigger signal at the camera starts the exposure and the subsequent image transfer. Upon completion of the data transfer, the IS_TRIGGER event signals that the camera is ready for the next capture. The IS_FRAME event is set once pre-processing (e.g. color conversion) is complete and the finished image is available in the user memory.

Hinweis

The following illustrations show a schematic view of the image capture sequence. The sensor exposure and readout times and the transmission times depend on the camera settings. The pre-processing time depends on the API functions you are using (e.g. color conversion, edge enhancement).

Figure 138: Events in hardware trigger mode

Figure 138: Events in hardware trigger mode

Events in Live Mode (Image Sequence)

The following figure shows the time sequence when triggering the IS_FRAME and IS_SEQUENCE events. The camera is set to live mode using is_CaptureVideo() so that it continuously captures frames. The IS_FRAME event is set once pre-processing (e.g. color conversion) is complete and a finished image is available in the user memory. The IS_SEQUENCE event is set after one cycle of a storing sequence has been completed (see also is_AddToSequence()).

Figure 139: <br>
Events in live mode

Figure 139:
Events in live mode

*) Optional function. The start time and duration of the flash signal are defined by the Flash delay and Duration parameters (see is_SetFlashDelay()).

Function List

is_DisableEvent()

Disables a single event object.

is_EnableEvent()

Enables a single event object.

is_EnableMessage()

Turns the Windows messages on / off.

is_ExitEvent()

Closes the event handler.

is_InitEvent()

Initializes the event handler.

is_EnableAutoExit()

Automatically releases the camera resources when the camera is disconnected from the PC.

Flowchart: Enable Events

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Figure 140: Flowchart - Enabling event handling

Figure 140: Flowchart - Enabling event handling

Flowchart: Enabling Messages

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Figure 141: Flowchart - Enabling message handling

Figure 141: Flowchart - Enabling message handling

Flowchart: Event / Message Handling

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Figure 142: Flowchart - Handling events / messages

Figure 142: Flowchart - Handling events / messages


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