1. An image decoding device comprising:
an intra prediction unit for generating an intra prediction image by carrying out an intra-frame prediction process on a coding block which is a unit for a prediction process, when a coding mode for the coding block is an intra coding mode,
wherein said intra prediction unit performs a process of generating an intermediate predicted value from reference samples according to an intra prediction parameter indicating a type of intra prediction, and obtaining a final predicted value by carrying out a filtering process for the intermediate predicted value according to a type of color component and the intra prediction parameter,
the intra prediction parameter indicates an average prediction mode, and
the filtering process is carried out only for a pixel in a specific position in the block.
2. An image decoding method comprising:
a step of generating an intra prediction image by carrying out an intra-frame prediction process on a coding block which is a unit for a prediction process, when a coding mode for the coding block is an intra coding mode;
a step of performing a process of generating an intermediate predicted value from reference samples according to an intra prediction parameter indicating a type of intra prediction; and
a step of performing a process of obtaining a final predicted value by carrying out a filtering process for the intermediate predicted value according to a type of color component and the intra prediction parameter,
wherein the intra prediction parameter indicates an average prediction mode, and
the filtering process is carried out only for a pixel in a specific position in the block.

3. An image encoding device comprising:
an intra prediction unit for generating an intra prediction image by carrying out an intra-frame prediction process on a coding block which is a unit for a prediction process, when a coding mode for the coding block which is obtained by dividing an inputted image is an intra coding mode,
wherein said intra prediction unit a process of generating an intermediate predicted value from reference samples according to an intra prediction parameter indicating a type of intra prediction, and obtaining a final predicted value by carrying out a filtering process for the intermediate predicted value according to a type of color component and the intra prediction parameter,
the intra prediction parameter indicates an average prediction mode, and
the filtering process is carried out only for a pixel in a specific position in the block.
4. An image encoding method comprising:
a step of generating an intra prediction image by carrying out an intra-frame prediction process on a coding block which is a unit for a prediction process, when a coding mode for the coding block which is obtained by dividing an inputted image is an intra coding mode;
a step of performing a process of generating an intermediate predicted value from reference samples according to an intra prediction parameter indicating a type of intra prediction; and
a step of performing a process of obtaining a final predicted value by carrying out a filtering process for the intermediate predicted value according to a type of color component and the intra prediction parameter,
wherein the intra prediction parameter indicates an average prediction mode, and
the filtering process is carried out only for a pixel in a specific position in the block.