Samsung NX1 has a 28.0MP APS-C (23.5 x 15.7 mm ) sized BSI-CMOS sensor and features DRIMe 5 processor. On the other hand, Canon 80D has a 24.0MP APS-C (22.5 x 15 mm ) sized CMOS sensor and features DIGIC 6 processor.
Another difference between these two cameras is that Samsung NX1's sensor lacks anti-alias (Low-Pass) filter. Removing anti-alias filter increases the sharpness and level of detail but at the same time, it increases the chance of moire occurring in certain scenes.
Below you can see the NX1 and 80D sensor size comparison.
Samsung NX1 and Canon 80D have almost the same sensor size so none of them has any significant advantage over other in this area.