The goal of the lensfun library is to provide a open source database
of photographic lenses and their characteristics. In the past there
was a effort in this direction, but then author decided to take
the commercial route and the database froze at the last public
stage. This database was used as the basement on which lensfun
database grew, thanks to PTLens author which gave his permission
for this, while the code was totally rewritten from scratch (and
the database was converted to a totally new, XML-based format).

The lensfun library not only provides a way to read the database
and search for specific things in it, but also provides a set of
algorithms for correcting images based on detailed knowledge of
lens properties. Right now lensfun is designed to correct distortion,
transversal (also known as lateral) chromatic aberrations, vignetting
and colour contribution of the lens (e.g. when sometimes people
says one lens gives "yellowish" images and another, say, "bluish").

Homepage:
https://lensfun.github.io/
