Defined line-crossing events occur only once

**• Hardware Platform:Jetson
**• DeepStream Version: 5.1
**• JetPack Version: 4.5.1
**• TensorRT Version:
**• Issue Type: Question


I have a problem with line-crossing feature of nvdsanalytics. I have defined two lines, Entry and Exit. Detected objects can trigger these events only once for each. If object crossed the Entry and Exit lines once for each, following line-crossings do not create events.

I need all crossing events until object is disappeared because of this. In some cases for my counting application, people crosses the lines for several times and I should ignore all the Entry&Exit pairs. If there is no event left after ignoring the pairs, this indicates that person kept his/her beginning position, actually did not enter/exit from that area. If there is only one Exit event left, that indicates person changed his/her beginning position, exit from that area. But as I mentioned, nvdsanalytics does not create any events after one Entry&Exit pair.

Alternative solutions may be;

  • Clear only lcStatus information of objects with an Entry&Exit pair each time, wait for disappear
  • Removing all metadata related to objects with an Entry&Exit pair, track with new id (act it like its a new detected object)

By now, I could not apply any of these solutions.

Do line-crossing really works like that or there is something wrong with my application or configurations ? If it works like that, how can I get what I need, any opinions ?

Sorry for the late response, is this still an issue to support?


Yes @kayccc I still need support about the issue.

Is it possible to use ROI?

Gst-nvdsanalytics — DeepStream 5.1 Release documentation (

Hello @kesong,

Thanks for reply. It makes sense to use ROI feature but I should try first. Actually I prefer to use line-crossing but as I understand from your advice, line-crossing works exactly like I mentioned before, am I right ?

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