Enabling Video Capturing from Webcam Inside a Docker Container

Enabling Video Capturing from Webcam Inside a Docker Container

Introduction: In this blog, we'll explore how to set up a Docker container to enable video capturing from a webcam while running a Python script. We'll use OpenCV, a popular computer vision library, and create a Docker environment that allows seamless webcam integration.

Prerequisites:

  1. Docker installed and running on the host machine.

  2. In my case, the host OS is Centos running on VirtualBox. So, the "Oracle VM VirtualBox Extension Pack" to establish the connection between the virtual machine and the laptop's camera.

Creating the Docker Environment:

  1. Dockerfile: The Dockerfile is a blueprint for creating a Docker image. It specifies the environment, dependencies, and commands for setting up the application. In our case, the Dockerfile would look like the one you provided.

     # Use a base image with Python and OpenCV
     FROM python:3.8
    
     # Install dependencies, including graphics libraries
     RUN apt-get update && \
         apt-get install -y libgl1-mesa-glx && \
         pip install opencv-python
    
     # Copy your Python script into the container
     COPY your_script.py /app/your_script.py
    
     # Set the working directory
     WORKDIR /app
    
     # Run your Python script
     CMD ["python", "your_script.py"]
    
  2. Building the Docker Image:

     docker build -t video-stream-app .
    
  3. Running the Docker Container:

     docker run --device /dev/video0:/dev/video0 --net=host -e DISPLAY=$DISPLAY -v /tmp/.X11-unix:/tmp/.X11-unix video-stream-app
    

Python Script: Let's examine the your_script.py Python script, which captures video from the webcam using OpenCV and displays it in a window.

import cv2

cap = cv2.VideoCapture(0)

while True:
    status, photo = cap.read()
    cv2.imshow("Webcam Video Stream", photo)

    # Press Enter key to exit
    if cv2.waitKey(10) == 13:
        break

cv2.destroyAllWindows()

Conclusion: Setting up a Docker container to enable video capturing from a webcam is a valuable skill for various applications, including video streaming, computer vision, and real-time image processing. With the integration of OpenCV and Docker, developers can create versatile and portable environments for working with video data. By following the steps outlined in this blog, you can effortlessly build a Docker container that captures webcam video and benefits from the capabilities of both Docker and OpenCV.

Note: Ensure that you have the necessary permissions and configurations to access the host's webcam and display when running Docker containers with video capabilities.