i use github opencv program and build docker file and then run it. I get error that
Traceback (most recent call last):
File “/home/torizon/opencv-example.py”, line 6, in
cv2.imshow(‘image’,img)
cv2.error: OpenCV(4.6.0) ./modules/highgui/src/window_gtk.cpp:635: error: (-2:Un specified error) Can’t initialize GTK backend in function ‘cvInitSystem’
Hi, I’m the Toradex AI Assistant. The Toradex Support team will follow up with you shortly!
Did you like my answer?
The error you’re encountering is related to the inability of OpenCV to initialize the GTK backend, which is required for displaying images using cv2.imshow. This issue often arises in headless environments, such as Docker containers, where there is no display server available.
In the context of using Torizon, the solution involves ensuring that the Docker container is set up to use a display server. The Torizon platform supports the Wayland protocol, which can be used as a backend for graphical applications.
Here are some steps you can take to resolve this issue:
-
Ensure Wayland is Running: Make sure that your Docker container is configured to use Wayland. The Torizon documentation mentions using a Wayland image from Toradex’s Dockerhub. Ensure your Dockerfile includes the
torizon/wayland-base-vivanteimage. -
Modify Docker Compose: Ensure your
docker-compose.ymlfile is correctly set up to start the necessary containers and bind mount the appropriate directories for Wayland support. This setup allows the application to communicate with the display server. -
Check Permissions: Ensure that the container has the necessary permissions to access the display server. This might involve setting the correct privileges in the Docker Compose file.
-
Use Weston: If not already done, ensure that Weston (a Wayland compositor) is running in your environment, as it is required for rendering the display.
By following these steps, you should be able to resolve the GTK initialization error and successfully display images using OpenCV in your Docker container on Torizon.
Please, also check if these links can help you solve your problem: