An image processing apparatus for sequentially generating rendering data of a plurality of images composing a moving image, comprising a velocity vector detecting unit for detecting a velocity vector of a block image in an image in accordance with the rendering data based on rendering basic data used for the generation of the rendering data and a control unit for selectively performing, for each of the block images of the rendering data and based on a velocity vector generated by the velocity vector detecting unit, subsampling processing for generating only part of the pixel data in the pixel data corresponding to the block image based on the rendering basic data and non-subsampling processing for generating all pixel data corresponding to the block image based on the rendering basic data to thereby generate the rendering data.