Apparatus and method for interpolating binary pictures

A context probable table of context template is employed in order to interpolate binary picture information. The context template for respective pixels making up the binary picture information is made, and probabilities for the interior of an object and the exterior of the object on its context indexes are obtained from the context probable table arranged previously. The probabilities for the interior and exterior of the object are compared with each other and the binary picture information is interpolated with a value having more probability.