The optimzed function improves the performance. The original function
always runs through the complete historgram of length 256 even if it
is possible to exit the loop early (break).
Running some tests I found performance improvements of factor >10
depending on the image.
Signed-off-by: Andreas Florath <andreas@florath.net>
Similar to the recent adoption of Black. isort is a Python utility to
sort imports alphabetically and automatically separate into sections. By
using isort, contributors can quickly and automatically conform to the
projects style without thinking. Just let the tool do it.
Uses the configuration recommended by the Black to avoid conflicts of
style.
Rewrite TestImageQt.test_deprecated to no rely on import order.
