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Xtium2-CXP PX8 Reference
Xtium2-CXP PX8 User's Manual
Metadata: Theory of Operation
The following provides additional details on the metadata implementation.
Metadata Data Structure
The Xtium2-CXP PX8 supports metadata at the end of each line when enabled through the
parameter CORACQ_PRM_META_DATA. The metadata consists of 64 bytes. The content of the
metadata represents a snapshot of the state of the frame grabber at the beginning of each LVAL
received.
typedef struct
{
ULONGLONG shaftEncoderCount;
ULONGLONG lineCount;
ULONGLONG lineTriggerCount;
ULONGLONG timeStamp;
ULONG frameCounter;
UCHAR generalInputs;
UCHAR generalOutputs;
UCHAR biDirectionalIOs;
UCHAR reserved[25];
} MX4_METADATA, *PMX4_METADATA;
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shaftEncoderCount: 64-bit counter of pulses received on the shaft encoder. This is a ‘machine
counter’ that increments in one direction (forward) and decrements (reverse) in the opposite
direction.
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lineCount: 64-bit counter of line valid (LVAL) received.
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lineTriggerCount: 64-bit counter of line triggers sent to the camera.
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timeStamp: 64-bit counter of the frame grabber on-board timestamp. See also
CORACQ_PRM_TIME_STAMP_BASE and CORACQ_PRM_TIME_STAMP.
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frameCounter: 32-bit counter of frames received. This represents the frame number that the
line belongs to.
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generalInputs: status of the general inputs (for example, Low, bit = 0 or High, bit = 1).
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generalOutputs: status of the general outputs (for example, Low, bit =0 or High, bit = 1).
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biDirectionalIOs: status of the bi-directional I/Os (for example, Low, bit = 0 or High, bit = 1).
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reserved: 25 bytes reserved for future usage.
Clearing Metadata Counters
To clear (reset) the metadata counters to zero (0), use the CORACQ_PRM_META_DATA_CLEAR
parameter.
Metadata Example
For a demo application showing this feature, please contact Teledyne DALSA technical support.
