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C2 Series User Manual Rev. 1.9
The C2 Series Chunk Data Mode
General Description
The C2 series features a Chunk Data mode for providing additional information to the acquired image
data. The implementation of XML nodes is performed according to SFNC 1.4:
Category ChunkDataControl
ChunkModeActive
ChunkModeSelector (OneChunkPerFrame, OneChunkPerProfile)
The ChunkData generated by the camera have the following format:
ChunkImage
1…N x ChunkAcqInfo
ChunkImageInfo
Depending on camera mode (image or 3D) the ChunkData block („ChunkAcqInfo“) can be sent as
follows:
In image mode, the camera can send only one ChunkAcqInfo block per image frame.
In 3D mode, the camera can send one ChunkAcqInfo block either per 3D frame
(“OneChunkPerFrame”) or per 3D profile (“OneChunkPerProfile”).
The „ChunkImageInfo“ is the last ChunkData sent by the camera and contains following data:
Number of valid rows in ChunkImage
Number of valid ChunkAcqInfo blocks
Flags identifying the current frame as „Start“ or „Stop“ and the buffer status in AutoStart mode
The ChunkAcqInfo block consists of totally 32 bytes containing following data
64 bit timestamp
32 bit frame counter
32 bit trigger coordinate
8 bit Trigger status
32 bit I/O Status
72 bit AOI information
The data of timestamp, frame counter, trigger coordinate, trigger status and I/O status are assigned
at the start of every image integration.
When ChunkMode is disabled, the camera uses the “regular“ GEV image protocol, in which the
optional transfer of frames with variable height and payload is supported.
Furthermore, when ChunkMode is enabled, the camera sends the full payload, even if the
ChunkImage or ChunkAcqInfo blocks contain partially valid data. The number of valid ChunkImage
rows and ChunkAcqInfo blocks can be read from ChunkImageInfo.
