1. A method for enhancing a spatio-temporal resolution of time-sequential depth frames of a scene, the method comprising: receiving time-sequential reflectance frames of pixel intensity values acquired of a scene by at least one reflectance sensing device; receiving time-sequential depth frames of pixel depth values of said scene acquired by at least one depth sensing device; and performing at least one of: (A) in response to a temporal resolution of said reflectance frames being greater than a temporal resolution of said depth frames, (i) selecting a time point where a depth frame does not exist in said sequence of depth frames; (ii) constructing at least one new depth frame based on correlations determined between motion patterns in said sequence of reflectance frames and said sequence of depth frames; and (iii) inserting said new depth frame into said sequence of depth frames at said selected time point; and (B) in response to a spatial resolution of said reflectance frames being greater than a spatial resolution of said depth frames, (iv) selecting a time point where a depth frame does exist in said sequence of depth frames; and (v) enhancing a spatial resolution of said existing depth frame at said selected time point based on correlations determined between a distribution of pixel intensity values of said reflectance frames and a distribution of pixel depth values of said associated depth frames.