atlas

atlas is a Python GUI for viewing FITS images, in the spirit of SAOImage DS9.

Installation

Requires Python 3.10 or higher.

pip install -e .# atlas and its runtime dependencies
pip install -e ".[zmq]"# also the optional ZMQ tool
pip install -e ".[dev]"# also pylint, for the CI checks

Dependencies are declared in pyproject.toml.

Usage

Installing puts an atlas command on your path:

atlas # defaults: single frame, header panel
atlas image.fits # open a file straight away
atlas *.fits --mode tile # every file in its own tile
atlas --profile minimal # image display and nothing else
atlas --config observing.yaml # your own configuration

It also runs straight from a checkout without installing:

PYTHONPATH=src python -m atlas.main --profile viewer image.fits

Run atlas --help for the full command line, and --list-profiles for the bundled profiles.

Frames

atlas borrows DS9's frame concept: each loaded image lives in its own frame, and the display mode decides how frames appear on screen.

Mode	What you see	Shortcut
single	one frame at a time	Ctrl+1
tile	every frame in a grid	Ctrl+2

Move between frames with Ctrl+] and Ctrl+[, or click a tile. Ctrl+W closes the current frame.

Configuration

A configuration is resolved from, in increasing order of precedence: built-in defaults, the --profile, the --config file, then command-line overrides. Unknown keys are rejected with an error rather than ignored, so a typo cannot silently leave a feature switched off.

window:
title: atlaswidth_fraction: 0.8# of the screenheight_fraction: 0.8display:
mode: single # single | tiletile_columns: null # null picks a roughly square gridtools:
header: true # FITS header panelhistogram: false # pixel-intensity histogramstap_subtraction: false # COO detector signal/reset tapszmq: false # load frames announced over ZMQ

Any tool taking options can be written either as a bare boolean or as a section:

tools:
tap_subtraction:
enabled: truetap_width: 128num_taps: 32zmq:
enabled: trueaddress: tcp://localhost:5555socket_type: SUB # SUB | PULLbind: false

Individual tools can be toggled from the command line without editing anything:

python src/main.py --profile minimal --enable histogram
python src/main.py --profile detector --disable zmq

Bundled profiles

Profile	Purpose
minimal	Image display only — no panels, no tools.
viewer	General FITS viewing: headers and histograms.
detector	COO detector work: tiled frames, tap subtraction, ZMQ.

Reporting Issues

If you encounter any problems or have questions about this project, please open an issue on the GitHub Issues page. Your feedback helps us improve the project!