Last eclipse newsletter 5.0

eclipse is an ANSI C library, focused mainly on image and 1d signal processing, with emphasis on infrared and visible images and spectra. The algorithms used in this library have usually nothing specific to astronomy, they gather the know-how in the field of image and signal processing and attempt to make them useful to write astronomical data processing programs.

eclipse is not meant to be an interactive facility. Accessing a C library can be done in many ways, but there are all reserved to a programmer. A C library remains a building block for developpers.

The primary goal of this toolbox is to allow people writing pipelines for the VLT to program dedicated routines aimed at data reduction for specific modes of VLT instruments. Programming pipelines from source code in C is much more flexible than using a high-level processing language, since it allows virtually infinite addition of new algorithms and complete control over these. The price to pay is of course low-level programming, which is a favourite playground for bugs of all kinds.

The library itself is today pretty mature, only occasional bugs are reported and usually corrected the same day by the supporting team. The code is simple, robust, commented and documented, and its foundations are laid on a clear and simple design.

To allow for more convenience when prototyping pipeline recipes, the library is currently being interfaced to several scripting languages. As a C library, it could be interfaced to virtually any kind of higher-level language (this includes C++, Java, Python, Perl, Tcl and many others). Linking against one of these languages should allow pipeline programmers to be more efficient in developping their carefully handcrafted toolboxes for a given instrument. This functionality is currently not planned to be supported for public distribution, though, because of the heavy load implied by such support.

The FITS read/write functionalities are offered by qfits.

References to eclipse should be made by quoting:
N. Devillard, "The eclipse software", The messenger No 87 - March 1997