Patent ID: 8791951

Claim:
An image synthesis apparatus comprising: at least one computer processor to provide: an input unit to receive from a user selected information on material information processing, sampling and rendering; a material information processing unit to convert measured material data into raw material data including measured Bi-directional Reflectance Distribution Function (BRDF) values, perform material model fitting on the raw material data to generate material information and perform material mixing on the material information to generate mixed material information, wherein the model fitting and the material mixing is performed according to the selected information; a sampling unit to sample the raw material data to generate sampling information in proportion to the measured BRDF values, the sampling unit including: a tabular cumulative density function calculator using cosine values of inverse altitudes as weights due to characteristics of a rendering equation, to generate a tabular-type cumulative density function on the raw material data and calculate an inverse function of the cumulative density function, and a tabular sampling calculator to apply the cumulative density function to generate the sampling information; a materials properties rendering unit to render scene information contained in the selected information, the mixed material information and the sampling information to generate surface material information; and an output unit to visualize the material information and the surface material information.