An image processing circuit inputs pixels of an RGB Bayer array therein. A chroma value calculation circuit calculates a chroma factor (KL) for evaluating the chroma of a surrounding area of a specified pixel. A correlation value calculation circuit calculates correlation values for gray image and color image. If the chroma factor (KL) is larger than a threshold value (TH1), a correlation judgment method for color image and a pixel interpolation method for color image are selected, if the chroma factor (KL) is not larger than a threshold value (TH1) and larger than a threshold value (TH2), a correlation judgment method using a correlation value obtained by overall judgment on the correlation values for gray image and color image and a pixel interpolation method for color image are selected, and if the chroma factor (KL) is not larger than a threshold value (TH2), a correlation judgment method for gray image and a pixel interpolation method for gray image are selected.