Troubleshooting#

This topic helps with diagnosing and resolving common issues encountered when working with pypylon and industrial cameras.

The focus is on practical debugging strategies and typical failure scenarios.

Typical Symptoms and Causes#

Symptom	Possible Cause
No camera detected	Driver missing, cable issue, SDK not installed
Timeout in `RetrieveResult()`	Trigger misconfiguration, no signal, wrong timeout
Dropped frames	Bandwidth limitation, slow processing
Grab errors	Network instability, packet loss
Application freezes	Blocking calls, deadlocks, queue overflow

Camera Detection Issues#

To resolve camera detection issues, you have two options:

Check the hardware:
- Verify cable connection.
- Verify camera power.
- Try a different USB port or Ethernet cable.
Check the software:
- Ensure that the pylon SDK is installed.
- Verify that the drivers are loaded.
- Test with the pylon Viewer.

Timeout Problems#

Typical Causes#

Trigger mode enabled but no trigger signal
Exposure time too long
Timeout value too low

Debugging Strategies#

camera.TriggerMode
camera.TriggerSource

Disable triggering for testing:

camera.TriggerMode.Value = "Off"

Grab Errors#

Indicators#

if not grab_result.GrabSucceeded():
    print(grab_result.ErrorDescription)

Typical Causes#

Network congestion (GigE)
Insufficient bandwidth
Unstable connection

Image Corruption and Frame Loss#

Typical Causes#

Packet loss (GigE cameras)
CPU overload
Insufficient buffers

Mitigation Strategies#

Enable jumbo frames.
Increase MaxNumBuffer.
Reduce ROI or frame rate.

Performance Issues#

Indicators#

Rising latency
Increasing queue sizes
Dropped frames

Debugging Strategies#

Measure frame rate.
Monitor CPU usage.
Inspect queue sizes.

Threading Issues#

Indicators#

Deadlocks due to blocking queue.get()
Threads not stopping on shutdown

Fixes#

Use timeouts:
```
q.get(timeout=0.1)
```
Use stop signals:
```
stop_event = threading.Event()
```

OpenCV GUI Issues#

Indicators#

QObject::killTimer error

Typical Cause#

GUI functions executed in worker thread

Fix#

Run cv2.imshow() only in main thread.

Network Issues (GigE)#

Indicators#

Packet loss
Frame drops

Mitigation Strategies#

Use dedicated network interface card (NIC)
Enable jumbo frames.
Adjust packet delay.

Debugging Checklist#

The first step is to identify which layer causes the issue.

Hardware → Transport → Driver → Application

Look for the following issue indicators:

Is the camera detected?
Does the pylon Viewer work?
Have you configured TriggerMode correctly?
Is the bandwidth sufficient?
Is the CPU overloaded?
Are queues blocking?

Logging Recommendations#

Use structured logging instead of print:

import logging
logging.exception("Camera error")

Key Takeaways#

Most issues are related to configuration or timing.
Always isolate hardware vs. software problems.
Monitor system resources continuously.
Use systematic debugging approach.