Xtium-CL PX4 User's Manual
Xtium-CL PX4 Reference
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Sapera Acquisition Methods
Sapera acquisition methods define the control and timing of the camera and frame grabber board.
Various methods are available, grouped as:
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Camera Trigger Methods (method 1 supported)
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Line Trigger Methods (method 1)
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Line Integration Methods (method 1 through 4 supported)
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Time Integration Methods (method 1, 3, 5, 6, 8)
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Strobe Methods (method 1, 3, 4 supported)
Refer to the Sapera LT Acquisition Parameters Reference manual (OC-SAPM-APR00) for detailed
information concerning camera and acquisition control methods.
Trigger to Image Reliability
Trigger-to-image reliability incorporates all stages of image acquisition inside an integrated
controller to increase reliability and simplify error recovery. The trigger-to-image reliability model
brings together all the requirements for image acquisition to a central management unit. These
include signals to control camera timing, on-board frame buffer memory to compensate for PCI bus
latency, and comprehensive error notification. If the Xtium-CL PX4 detects a problem, the
application can take appropriate action to return to normal operation.
The Xtium-CL PX4 is designed with a robust ACU (Acquisition and Control Unit). The ACU monitors
in real-time, the acquisition state of the input plus the DTE (Data Transfer Engine) which transfers
image data from on-board memory into PC memory. In general, these management processes are
transparent to end-user applications. With the Xtium-CL PX4, applications ensure trigger-to-image
reliability by monitoring events and controlling transfer methods as described below:
Supported Events and Transfer Methods
Listed below are the supported acquisition and transfer events. Event monitoring is a major
component to the Trigger-to-Image Reliability framework.
Acquisition Events
Acquisition events pertain to the acquisition module. They provide feedback on the image capture
phase.
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External Trigger (Used/Ignored)
Generated when the external trigger pin is asserted, which indicates the start of the
acquisition process. There are two types of external trigger events: ‘Used’ or ‘Ignored’.
Following an external trigger, if the event generates a captured image, an External Trigger
Used event will be generated (CORACQ_VAL_EVENT_TYPE_EXTERNAL_TRIGGER).
If there is no captured image, an External Trigger Ignored event will be generated
(CORACQ_VAL_EVENT_TYPE_EXTERNAL_TRIGGER_IGNORED). An external trigger event is
ignored if the event rate is higher than the possible frame rate of the camera.
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Start of Frame
Event generated during acquisition, with the detection of the start of a video frame by the
board acquisition hardware. The Sapera event value is
CORACQ_VAL_EVENT_TYPE_START_OF_FRAME.
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End of Frame
Event generated during acquisition, with the detection of the end of a video frame by the
board acquisition hardware. The Sapera event value is
CORACQ_VAL_EVENT_TYPE_END_OF_FRAME.
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Data Overflow
The Data Overflow event indicates that there is not enough bandwidth for the acquired data
transfer without loss. Data Overflow would occur with limitations of the acquisition module
