Lens Correction only uses one core

[Torsten Bronger]

Hallöchen!

Hans-Peter writes:

> i noticed that automatic lens correction (currently DK 5.5) is
> very slow and uses only one CPU core. When doing this in Gimp
> (lensfun-plugin), its way faster and uses all cores.
>
> Is this a bug or are there some reasons for this?

Lensfun indeed contains no parallel execution of code.  I don't know
for sure why this is but I suspect that the original Lensfun
designer expected the calling program to vectorise tasks.  For
example, different regions of the image can be corrected calling
Lensfun concurrently.  Moreover, when mass-converting RAWs to JPEGs,
images can be processed in parallel.

Having parallel execution on both levels, Lensfun and
Digikam/Darktable/whatever, is probably not a good idea.

Tschö,
Torsten.

-- 
Torsten Bronger