vortex-tracker

OpenCV-based analysis script for measuring vortex ring diameter over time from image sequences.

Developed for IISc internship workflow experiments.

What The Script Does

File: vortex_tracker.py

• Loads image frames from a folder
• Converts each frame to grayscale and blurred image
• Applies fixed binary thresholding
• Finds largest contour as vortex region
• Measures vertical diameter from topmost to bottommost contour points
• Converts pixels to centimeters using calibration constant
• Logs per-frame diameter measurements
• Plots diameter vs time (assuming fixed 500 FPS)

Calibration and Inputs

Current constant:

• PIXELS_PER_CM = 566 / 2.5

Before running, set these paths in the script:

• folder_path - input image directory
• project_folder - output/log directory

Outputs

• vortex_diameters_log.txt
• vortex_Diameter_changes.png
• optional append from Diameter_of_vortex.txt if present

The repo also includes sample assets/logs:

• frame images under vortex_images/
• historical speed and diameter logs
• generated diameter plots

Run

python vortex_tracker.py

Dependencies

pip install opencv-python numpy matplotlib

Limitations

• Uses fixed thresholding tuned to specific capture conditions
• Assumes largest contour is always the vortex boundary
• Time axis assumes 500 FPS; adjust if your capture rate differs
• Requires manual path setup in script before execution