Скачать или смотреть How to Fix the GoPro Hero4 Livestream Issue in C+ + with OpenCV

Learn how to resolve the `GoPro Hero4` livestream not opening in C+ + using OpenCV, even while it works perfectly in Python. We will guide you through common pitfalls and share the ultimate solution!
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Troubleshooting GoPro Hero4 Livestream Issues in C+ + with OpenCV

Introduction

If you’re attempting to perform image processing on a GoPro Hero4 Black livestream using OpenCV in C+ + , you may find a frustrating issue where the livestream successfully opens in Python, but fails to do so in C+ + . Specifically, the VideoCapture object reports that it is not open, despite seemingly successful command executions. This guide will help you understand the problem and how to overcome it effectively.

Understanding the Problem

A user has encountered a scenario where the following things happen:

The connection to the livestream is established in both Python and C+ + .

The cap.open(...) command in C+ + takes too long and subsequently returns false when checking the capture status with cap.isOpened().

While the user provided code snippets in both Python and C+ + , the key steps seem similar; hence, the performance discrepancy raises questions about environmental issues or software configurations.

Initial Code Snippets

Python Code - Working Example

[[See Video to Reveal this Text or Code Snippet]]

C+ + Code - Problematic Attempt

[[See Video to Reveal this Text or Code Snippet]]

Solution Overview

The solution to this issue can be surprisingly simple: the firewall settings. More specifically, it has been noted that disabling the Windows Firewall for private networks may resolve the problem where the C+ + application cannot open the UDP livestream, while the Python environment works seamlessly.

Step-by-Step Solution

Check Firewall Settings:

Go to the Windows Control Panel.

Click on "System and Security" and then "Windows Defender Firewall".

Choose "Turn Windows Defender Firewall on or off" on the left menu.

Disable it for private networks temporarily to test your application.

Test the C+ + Code Again:

After altering your firewall settings, re-run your C+ + application.

Ensure that cap.isOpened() now returns true.

Re-enable Firewall:

If the livestream opens successfully, consider creating specific firewall rules to allow traffic on the required ports (e.g., UDP ports used by your GoPro).

Alternative Troubleshooting Steps

If the firewall suggestion doesn’t resolve your issue, consider the following additional checks:

Network Configuration: Ensure your laptop is on the same network as the GoPro.

OpenCV Configuration: Verify that your OpenCV build supports the VideoCapture backend you are using for UDP.

API References: Experiment with different API references such as CAP_ANY or CAP_FFMPEG with the cap.open(...) method.

Conclusion

Although it may seem trivial, Windows Firewall settings can significantly affect the ability to connect devices using UDP protocols. If you find yourself in a situation where your C+ + code does not behave like your Python code regarding the GoPro livestream, ensure you've checked your firewall settings first. Happy coding, and may your livestreams be seamless!