GalMEx: Galaxy Morphology Extractor

GalMEx (Galaxy Morphology Extractor) is a Python package for robust, modular, and reproducible measurement of non-parametric galaxy morphology indicators. It includes implementations of the CAS and MEGG systems, along with complete image preprocessing, segmentation, and light profile analysis tools.

Now available as a command-line tool (galmex) and a graphical interface (GUI).

🚀 Installation

You can install GalMEx from PyPI:

pip install galmex

Alternatively, install the development version from GitHub:

git clone https://github.com/vitorms99/galmex.git
cd galmex
pip install .

Make sure the conda-forge channel is active if using conda:

conda config --add channels conda-forge
conda config --set channel_priority strict

💻 Usage Options

✅ Graphical User Interface (GUI)

To launch the GalMEx GUI:

galmex

Without any arguments, GalMEx will open the graphical interface for interactive configuration, inspection, and processing.

✅ Command Line Interface (CLI)

You can also run GalMEx from the command line using a config file:

galmex path/to/config.json

• If the specified CSV output file exists, you'll be asked whether to overwrite or rename.
• A progress bar and optional detailed logging are provided.
• A .log file and a copy of the final config are saved for each run.

📦 Features

• Background subtraction and noise estimation
• SExtractor- and SEP-based object detection
• Galaxy segmentation using Petrosian radius and surface brightness
• Measurement of:
  • CAS (Concentration, Asymmetry, Smoothness)
  • MEGG (M20, Entropy, Gini, G2 Asymmetry)
• Growth curve and characteristic radii (R50, R80)
• Optional GUI for visual inspection and customization
• Fully modular class structure (can be used as a library)

📄 Code Example

from galmex.Background_module import BackgroundEstimator

bkg = BackgroundEstimator("galaxy001", image)
bkg_median, bkg_std, bkg_map, img_clean = bkg.background_from_config({
    "bkg_method": "frame",
    "image_fraction": 0.1
})

🧪 Examples & Demos

The Examples/ folder includes:

• Functions_description.ipynb: full demo of all public methods
• Pre-generated example outputs used in the official manual

🛰️ SExtractor Integration (optional)

To use detection_mode="sex" in detection, install SExtractor:

conda install -c conda-forge astromatic-source-extractor

Make sure sex is callable from the terminal, or set an alias:

alias sex='path/to/sextractor'

📚 Documentation

• Full user manual (GalMEx_Manual.pdf) included
• Describes all classes, input parameters, example figures

🔗 Repository

📁 GitHub: https://github.com/vitorms99/GalMEx

👤 Author

Vitor Medeiros Sampaio
Universidad Técnica Federico Santa María — CHANCES Collaboration
📧 vitorms999@gmail.com

📝 License

MIT License