refine1D_2        243 modules/features2d/src/brisk.cpp   refine1D_2(const float s_05, const float s0, const float s05, float& max) const; // around octave 0 only
refine1D_2       1322 modules/features2d/src/brisk.cpp       scale = refine1D_2(max_below_float, std::max(float(center), max_layer), max_above, max);