In generation of a system header included in an program stream of extended MPEG-2 Systems, when a basic stream ID is an extension ID and basic buffer size information represents 0 byte, extension buffer size information expressed by a total of 24 bits of an extension ID, a marker bit and an extension stream ID and a total of 24 bits including an extension stream ID, a marker bit and extension buffer bound scale information and required for reproduction of an elementary stream to be multiplexed using a pair of an extension ID and an extension stream ID is generated and recorded.