1. An information processing apparatus that generates an indirect illumination buffer for a specular reflection used for rendering a 3D scene, comprising: a determination unit which is able to determine a viewpoint parameter for which the indirect illumination buffer is to be rendered; an acquisition unit which is able to acquire a low resolution indirect illumination buffer having a resolution less than the indirect illumination buffer, and information used for identification of reflection characteristics of objects in the 3D scene corresponding to the pixels of the indirect illumination buffer to be generated and specular reflection directions in positions of the objects; and a generation unit which is able to generate the indirect illumination buffer by increasing the resolution of the low resolution indirect illumination buffer acquired by said acquisition unit, wherein said generation unit generates a pixel of the indirect illumination buffer generated by the increase in resolution based on at least a level of similarity of specular reflection lobes, between an object corresponding to the pixel and an object corresponding to a pixel of the low resolution indirect illumination buffer used for generation of the pixel, for an eye direction defined by the viewpoint parameter determined by said determination unit and information used for identification of the specular reflection direction of each object.