1. An image processing apparatus comprising: an input unit configured to input image data including image components; an image processor configured to process the input image data; a generating unit configured to generate plane mesh image data representing a plane mesh image having equally spaced grid lines and transform the plane mesh image data by changing one of the space and the tilt angle of the grid lines, wherein the transforming of the plane mesh image data is performed according to a distortion presented in the input image data; and an adding unit configured to add the transformed mesh image data to the image data processed by the image processor.