The present invention relates to an image processing apparatus and a method for controlling the same. The image processing apparatus for applying film grain effects on an image of received image data includes a generating unit configured to generate, on the basis of pixel values randomly read from grain data including a plurality of pixel values, a basic grain image having a certain size larger than the grain data; a resizing unit configured to resize the basic grain image generated by the generating unit to have the same size as the received image data; and a combining unit configured to combine the basic grain image resized by the resizing unit with the received image data.