ROI movement
The sequencer enables the possibility of ROI position changing from one image acquisition to the next. This for example allows the “tracking” and “extraction” of moving objects within a larger field of view.
The figure shows the example of a vial that is moved thru the scene by a conveyer belt. The application aims for the inspection of the vial itself and thus all other image information is useless. In order to extract the vial, the ROI has to move from one image to the next.
Desired camera behavior
The theoretical approach is to set the camera to trigger mode and for each incoming trigger signal an image with specific, pre-configured partial scan settings is recorded.
Concept for the sequencer procedure
Taking into consideration the sequencer basics and the technical constraints makes sequencer parameterization a little bit more complex than originally expected:
- Since every image features its own partial scan parameterization, they all need a separate sequencer set.
- Besides the exposure time configuration each set contains the desired partial scan configuration including ROI height, ROI width, Offset x and Offset y as well as sequencer set and path related information.
Implementation
Since any image shall be recorded in response to an incoming trigger, the TriggerMode needs to be turned ON and a TriggerSource needs to be defined. For this example this is Line0 where the hardware trigger is attached to.
Sequencer sets
For this example, the sequencer sets differ regarding ROI configuration and SequencerSetNext settings.
SequencerPathSelector = 0
Defines the path for switchover to the next sequencer set. Here it is Path0.
ExposureTime = t
Defines the exposure time for the recorded image.
SequencerTriggerSource = ExposureActive
Defines the internal or external signal that is used as sequencer trigger source, here the internal signal ExposureActive.
SequencerTriggerActivation = RisingEdge
Defines the signal status change triggering switchover to the next sequencer set. In the example it is the RisingEdge.
SequencerSetNext
Defines which sequencer set is next in this path.
Set0: SequencerSetNext = 1
Set1: SequencerSetNext = 2
Set2: SequencerSetNext = 0
Result
The figure below shows the resulting images of the described sequence. The vial is virtually cut out within the camera by moving the ROI over the image.
Related topics
Support
Please contact our Technical & Application Support Center with any questions.
Phone: +49 3528 4386 845
E-mail: [email protected]