Object detection with centroid-based tracking: with Python

This repository demonstrates how to implement object detection and tracking the found objects. For demonstration, I implemented this by tracking cards.

ei_object_detection_and_tracking.py uses OpenCV to capture camera's images that are then passed to a loaded YOLOv5 model that was trained on Edge Impulse Studio. Using Edge Impulse's Linux Python SDK the classifier returns the bounding boxes of found cards. These bounding boxes are then passed to centroid_tracker.py that implements a centroid-based tracking algorithm. This centroid-based tracking script was implemented by PyImageSearch. The resulting image, card's bounding boxes, and number of tracked cards is then displayed on a window.

Please read up on the project's documentation on hackster.io page to help you get started on your own creation.

Quick start 💻

You can find the public Edge Impulse project here: Object detection and tracking. Feel free to clone it to your Edge Impulse projects.

Since the object detection script uses Edge Impulse Linux Python SDK, it is important that the scripts are run on a Linux-based computer. If you are on Windows I can confirm that the project runs fine on WSL 👍. You can use MJPEG Streamer to stream camera images, and XServer to open the OpenCV window. Lastly, run the scripts with Python3! Using Python will result in an error message like the one below:

Error message: File "ei_object_detection_and_tracking.py", line 71 print('Result (%d ms.) ' % (res['timing']['dsp'] + res['timing']['classification']), end='') ^ SyntaxError: invalid syntax

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Clone the repository using Git

git clone https://github.com/SolomonGithu/object_detection_and_tracking-centroid_based_algorithm.git

Navigate into the repository

cd object_detection_and_tracking-centroid_based_algorithm

Install OpenCV for Python:

pip3 install opencv-python

Install Edge Impulse Linux Python SDK:

sudo apt-get install libatlas-base-dev libportaudio0 libportaudio2 libportaudiocpp0 portaudio19-dev
pip3 install edge_impulse_linux -i https://pypi.python.org/simple

If you receive an error message unable to locate package portaudio you can run the command below, followed by the pip3 command to install edge_impulse_linux:

sudo apt get install python-pyaudio

Install the scipy package that is required by centroid_tracker.py:

pip3 install scipy

Start the project by running the command:

python3 ei_object_detection_and_tracking.py

• If you get the error message below, then you will need to identify your camera id and change the value of camera_id in ei_object_detection_and_tracking.py

[ WARN:0] global /io/opencv/modules/videoio/src/cap_v4l.cpp (802) open VIDEOIO ERROR: V4L: can't open camera by index 0

Tracking different objects 🚀

Changing the tracked object is very simple and I would highly recommend training and deploying the Machine Learning model using Edge Impulse. To do this, please follow the following steps:

• Train a Machine Learning model on Edge Impulse Studio and deploy it for Linux targets (this will be a .eim executable)
• Copy the downloaded .eim to the modelfile folder
• Update the modelfile path in ei_object_detection_and_tracking.py to match the name of your downloaded .eim file
• Update the targeted class name which should be the same class name used in your Edge Impulse project. This target class is defined at if(bb['label'] == 'card') . In this case card is the target class.