Patent ID: 7103069

Claim:
A block forming method whereby a digital bit stream consisting of a plurality of packets is converted into a data block and at least a main data portion in which a plurality of complete packets and at least one partial packet consisting of only partial data can be arranged and an additional data portion in which additional data of each of said complete packets in said main data portion and additional data of one partial packet are stored are formed at different positions of said data block, respectively, comprising the steps of: when a space area smaller than one packet occurs in an end portion of said main data portion, storing, as a partial packet, a part of the data of a next packet into said space area, storing additional data of said next packet into said additional data portion as additional data of the one partial packet, and storing, as a partial packet, remaining data of the part of the data of said next packet into a start portion of the main data portion of a next data block; and when said space area does not occur in the end portion of said main data portion, showing that the additional data of the one partial packet is invalid in said data block.