An imaging apparatus includes an imaging unit, a signal processing unit, and a pixel interpolation processing unit. The apparatus calculates a correlation degree for pairs in two orthogonal directions for an image signal obtained by the imaging unit including a single-chip image sensor having a four-color filter, such as a WRGB color filter, using pixel data in an area around a target pixel, using the correlation degree as a determination criterion in the interpolation. When a color component pixel with an identical color of a color component pixel subjected to pixel interpolation is not located in the direction having the high correlation, the pixel interpolation apparatus changes ratio in a direction orthogonal to the direction having the high correlation by using a pixel value resulting from color space conversion in the direction orthogonal to the direction having the high correlation, and performs pixel interpolation based on the change ratio.