NoiseChisel is a program to detect very low signal-to-noise ratio (S/N) features with minimal assumptions on their morphology. It was introduced in 2015 and released within a collection of data analysis programs and libraries known as GNU Astronomy Utilities (Gnuastro). Over the last ten stable releases of Gnuastro, NoiseChisel has significantly improved: detecting even fainter signal, enabling better user control over its inner workings, and many bug fixes. The most important change may be that NoiseChisel's segmentation features have been moved into a new program called Segment. Another major change is the final growth strategy of its true detections, for example NoiseChisel is able to detect the outer wings of M51 down to S/N of 0.25, or 28.27 mag/arcsec2 on a single-exposure SDSS image (r-band). Segment is also able to detect the localized HII regions as "clumps" much more successfully. Finally, to orchestrate a controlled analysis, the concept of a "reproducible paper" is discussed: this paper itself is exactly reproducible (snapshot v4-0-g8505cfd).
- Pub Date:
- September 2019
- Astrophysics - Instrumentation and Methods for Astrophysics;
- Astrophysics - Astrophysics of Galaxies;
- Computer Science - Computer Vision and Pattern Recognition
- Invited talk at IAU Symposium 355 (The Realm of the Low Surface Brightness Universe). The downloadable source (on arXiv) includes the full reproduction info (scripts, config files and input data links) and can reproduce the paper automatically. It is also available with its Git history in https://gitlab.com/makhlaghi/iau-symposium-355 , and in Zenodo at https://doi.org/10.5281/zenodo.3408481