Both Fujifilm X70 and Samsung WB800F have 16.0 MP resolution sensors but Fujifilm X70's sensor is APS-C (23.6 x 15.6 mm ) and Samsung WB800F's sensor is 1/2.3-inch (6.17 x 4.55 mm ).
Since Fujifilm X70's has a larger sensor area with the same resolution, this means that it also has a larger pixel area hence better light collecting capacity for a given aperture compared to Samsung WB800F.
Below you can see the X70 and WB800F sensor size comparison.
As seen above, Fujifilm X70 has a 13.1x Larger sensor area than Samsung WB800F. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in same focal length and aperture.