Scalable video encoding method, scalable video encoding apparatus, scalable video encoding program, and computer readable recording medium storing the program

A scalable video encoding apparatus that scalalably encodes videos, comprising:

• a correspondence table creating unit that, based on information about an optimum prediction mode that was selected in scalable encoding performed without any limits being placed on the usage of prediction modes defined as being able to be used, determines incidence rates of combinations of optimum prediction modes to be selected for spatially corresponding blocks of an upper layer and a lower layer, and creates a correspondence table that describes relationships between combinations of the selected optimum prediction mode and the optimum prediction mode to be selected, and the incidence rates;
• a prediction mode correspondence information creating unit that, based on the values of the incidence rates, extracts a combination of effective optimum prediction modes by narrowing down the combinations of the selected optimum prediction modes described in the correspondence table and the optimum prediction mode to be selected, and creates prediction mode correspondence information that describes the combinations of the extracted effective optimum prediction modes;
• an acquiring unit that, when encoding the upper layer block, acquires information about the optimum prediction mode selected in the encoding of the spatially corresponding lower layer block;
• and
• a deciding unit that, by referring to the prediction mode correspondence information using as a key the information about the selected optimum prediction mode acquired by the acquiring unit, the prediction mode search candidate to be searched in the encoding of the upper layer block is decided.