Link

collectra.Link refers to another artefact through its first parent ID. Classifiers use it to label an image or crop without duplicating that image:

Pollen:
  type: collectra.Link
  id: classification-001
  parents: image-001

The referenced image must also be present in the results. Python’s resolve() returns the target artefact. Links are used for classification training labels as well as predictions.

Commands

evaluate PREDICTED_FOLDER GOLD_FOLDER is the only Link command. Use the class node name and the shared evaluation options:

collectra --pipeline pipeline.yaml artefact Pollen evaluate predictions gold --output pollen-metrics.csv
collectra --pipeline pipeline.yaml artefact Pollen evaluate --help

For unresolved Links, comparison uses the parent IDs, so predicted and reference results should preserve source IDs. If both Links have resolved targets, the comparison delegates to the target artefacts; those targets must support evaluation. Whole Images do not implement an evaluation score.

Link nodes do not expose extract. Extract images from their source Image or ImageCrop node instead.