chunk parser, setting of chunk selector nodes

[SebastianRiedel]

Description

Follow-up to the How to set a Chunk Selector node? discord discussion.

It is a about accessing scale and offset values per channel ABC for conversion of point cloud data in the abstract format Coord3D_ABC16 to metric values like [mm]. These values seem to be transferred via chunk data and access needs to go through a selector node.

Noteworthy documentation from Mechmind:

• HALCON Genicam examples
• Mechmind Documentation on Obtaining Point Cloud Data from Depth Map in Custom Development with GenICam

What I can confirm at this point using the code snippet in the How to set a Chunk Selector node? original post is:

• I get the exact same offset for all coordinates ABC
• offset and scale change per image acquisition, so they are not static

Describe the solution you'd like

Describe alternatives you've considered

• todo: provide minimal sample code and output to further elicit the problem
• todo: double check to confirm proposed approach in discord doesn't work, cf. https://aravis-project.discourse.group/t/how-to-set-a-chunk-selector-node/787/2?u=sebastianriedel

Additional context

arv-tool 0.8.30: genicam xml and features.txt attached:
arv_tool_mechmind_nano.zip

[EmmanuelP]

Hi,

Please try #912

The Genicam data look wrong though. The access to the offset chunk only uses ChunkComponentSelector. A ChunkScan3dCoordinateSelector feature is defined but never used for chunk data access. I don't see how what is described in your camera documentation could work.

[EmmanuelP]

Any news ?

[SebastianRiedel]

I'm sorry, priorities shifting a lot and everything is urgent... I want to test it again in order to give an update, but need to find the time still.