The invention provides a pixel interpolating method including a step of discriminating, based on an input image signal, a similarity of a discrimination block constituted of plural pixels, and a reference block constituted of plural pixels, positioned close to the discrimination block and shifted upwards or downwards to a position by at least a line with respect to the discrimination block, and a step of outputting, as pixel information of an interpolation pixel positioned between a discrimination block and a reference block having a high similarity, pixel information based on pixel information of a pixel of the discrimination block and/or the reference block having the high similarity.