Fixed point calculation for improved accuracy, dithering in debug builds only.
Averaging and optional multiplier can be set as compile flags, example for speed testing with long averaging and a 10x multiplier:
-D FPS_CALC_AVG=200
-D FPS_MULTIPLIER=10
The calculation resolution is limited (9.7bit fixed point) so values larger than 200 can hit resolution limit and get stuck before reaching the final value.
If WLED_DEBUG is defined, dithering is added to the returned value so sub-frame accuracy is possible in post-processingwithout enabling the multiplier.