Plot Extractor / Curve Digitizer

Plot Extractor (with care) is a simple PyQt-based tool that allows you to digitize data points from plotted curves inside images. Load a graph image, define the coordinate system, add curves, and click points — the tool converts pixel clicks into real-world X/Y values (linear or logarithmic) and exports them to CSV.

✨ Features

✔ Load an image file (JPG/PNG/BMP etc.)

✔ Define the chart coordinate system manually (in pixels)

✔ Support for linear or logarithmic X/Y axes

✔ Add multiple curves with names & colors

✔ Click to create ordered data points per-curve

✔ Optional point-editing mode

✔ Normalizes pixel coordinates properly even if the window is resized

✔ Export curve data to CSV files

✔ Last-saved folder remembered when exporting

🖥️ Screenshot

🚀 Installation

Requirements

• Python 3.8+

• PyQt5

• NumPy

Install dependencies:

pip install pyqt5 numpy

(Add others like matplotlib if you later use them.)

🧰 Local Installation

pip install -e <Repository Dir>

Example:

pip install -e C:\Repos\PlotExtractWithCare\

Install From pypi:

pip install plotextractwithcare

▶️ Running the Application

python -m plotextractwithcare

📌 How It Works

Load an image

Enter the pixel locations of the origin and axis endpoints

Enter the real-world coordinate values (min/max for X and Y)

Choose whether X and Y are linear or log scale

Add a curve and begin clicking points

Export your data to CSV when done 🎉

Points are always kept sorted by X-value automatically.

📝 CSV Export Format

Exports contain two columns:

x,y 1.23,4.56 ...

⚠️ Disclaimer

Curve Digitizer is provided without any warranty. See the license section for more details.

📄 License

Plot Extractor (with care)

Copyright © 2026 Gadi Lahav — RF With Care Contact: gadi@rfwithcare.com

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 3 (GPLv3) or (at your option) any later version.

You should have received a copy of the GNU General Public License along with this program. If not, see: https://www.gnu.org/licenses/

🤝 Contributing

Pull requests and feature suggestions are welcome!

🙏 Acknowledgements

Thanks to the open-source community for the tools and libraries that make this possible