1. An imaging apparatus comprising: an imaging element having two-dimensionally arranged imaging pixels that receive light of an image formed by an optical system and output pixel signals corresponding to the received light, and in which non-imaging pixels, different from the imaging pixels, are arranged amongst the imaging pixels; continuity detection means for detecting whether a continuity of the pixel signals exists in at least one predetermined direction based on the pixel signals of the imaging pixels arranged around the non-imaging pixels; and calculation means for determining a pixel signal at a position of the non-imaging pixels by processing a pixel output of the imaging pixels arranged around the non-imaging pixels and based on whether any continuity was detected in the at least one predetermined direction, wherein the imaging pixels are arranged such that imaging pixels of a plurality of types having different spectral characteristics are arranged with different densities; and the calculation means performs by different processes, a calculation of the pixel signals for the non-imaging pixels provided at a position of the imaging pixels arranged at a relatively high density in the imaging pixels of the plurality of types, and a calculation of the pixels signals for the non-imaging pixels provided at a position of the imaging pixels arranged at a relatively low density in the imaging pixels of the plurality of types.