SpeckleStack

A Python/Tkinter desktop application for stacking FITS speckle imaging frames with sub-pixel alignment.

Features

• Frame stacking — combine multiple FITS frames using median, mean, or sum
• Sub-pixel alignment — FFT phase cross-correlation alignment before stacking
• 3-sigma clipping — optional outlier rejection before combining
• Auto reference frame — automatically selects the best reference frame, or specify one manually
• Live preview — stacked result displayed with adjustable black/white levels and Auto Stretch
• Activity log — real-time progress during stacking
• Save FITS — export the stacked result as a FITS file

Requirements

• Python 3.10+ with the following packages:
  • numpy
  • astropy

Installation

pip install numpy astropy
python specklestack.py

Building the Executable

Requires PyInstaller:

pip install pyinstaller
pyinstaller SpeckleStack.spec

The onedir build will be created in the dist/ folder.

Usage

1. Click Browse Input to select a folder of FITS frames.
2. Click Browse Output to choose where the stacked result will be saved.
3. Choose a Combine method (median recommended for speckle imaging).
4. Enable Align frames for sub-pixel FFT alignment.
5. Optionally enable 3-sigma clipping and Auto-select best reference frame.
6. Click Stack Frames and monitor progress in the Activity Log.
7. Click Save FITS to write the result to disk.

License

MIT License — © Arthur T. Trail 2026. See LICENSE for details.