Processor: Intel(R) Core i7-3630QM CPU @ 2.40GHz
RAM: 8x2 GB DDR3 1600Mhz
OS: Windows 10 Pro x64
Scene1: running time: with elliptic filtering: 2s; Without filtering, 1s.
Rendered Result, with filtering
Something interesting that even I implemented texure filtering of secondary ray( reflection and refraction), the final results seem not good as expeted.
Note the reflected checkerboard texture on the two spheres and on the ground. Texture on the ground is obviously more smooth.
Compared with the picture without filtering, there is great improvement of texture on the teapot and ground, but no much on the reflected ones on the two spheres.
Rendered Result, without filtering