Knowledge Base

Problem

Users are unsure how to determine the correct Green Intensity Threshold before acquisition, and whether changing the threshold for one run affects other runs or future acquisitions.

Details

The Green Intensity Threshold controls how many pixels are classified as paw contact. Setting it too high may miss dim prints; setting it too low may introduce noise. Applies to CatWalk XT 10.x and 11.x. Threshold changes during classification reprocess the selected run only and do not alter the recorded acquisition data or affect other runs automatically.

Solution

Setting the threshold before acquisition:
1. Open the Classification panel and perform a test run with a representative animal.
2. Adjust the Green Intensity Threshold until paw prints are clearly detected without excessive background noise.
3. Record the value – use this same value for all runs in the experiment to ensure comparability.

Adjusting the threshold for an individual run during classification:
1. Select the specific run in the Classification panel.
2. Adjust the Green Intensity Threshold for that run. This reprocesses only that run; it does not change already-classified runs or set the threshold for future runs.
3. To maintain consistency across runs that will be statistically compared, apply the same threshold value to all runs in the experiment.
4. Document the threshold value used in your experimental notes.