Patent ID: 8363941

Claim:
A method for extracting a number of silhouettes representing an object from a number of object images in which the object and a background are captured and a number of background images in which only the background is captured comprising: a first extract step of extracting a number of first silhouettes from the number of said object images and the number of said background images by a background subtraction; a first construct step of constructing a first visual hull from the number of said first silhouettes by a shape from silhouette method; a second construct step of constructing a second visual hull by a process to repair missed parts or to remove unwanted regions in said first visual hull; and a second extract step of extracting a number of second silhouettes from said second visual hull, wherein the steps are performed by a processor, said second construct step further including a sub step of acquiring a number of first slice images of said first visual hull from an x-axis, a y-axis and a z-axis direction; and a sub step of performing a filter process to the number of said first slice images and constructing said second visual hull according to a result of said filter process, and said sub step of constructing said second visual hull is a step of constructing said second visual hull by performing a filter process to the number of said first slice images, by searching for pixels that became white by the filter process, wherein white represents the object region, and black represents background, and by repairing three dimensional coordinates of said first visual hull corresponding to said pixels.