CyclesAdaptiveCriterion
Cycles' criterion (adaptive_sampling.h, E2): the error of a pixel is sum |I - A| / (1e-4 + sqrt(sum I)), with I the mean of all samples and A the mean of half of them. A pixel stops after the minimum samples when its error and its eight neighbors' are under the threshold, so a converged pixel beside a noisy one goes on, as Cycles' filter of the convergence mask does.
In the namespace construct::pathtrace. Declared in src/libs/libconstruct/construct/pathtrace/AdaptiveCriterion.hpp.