Patent ID: 7545864

Claim:
A picture encoding apparatus for generating a bit stream, the bit being compatible with MPEG 1 moving picture video standard and comprising an extension byte in at least a header of a specified layer of the bit stream, the extension byte being extension data added when a header includes control data newly added in MPEG2 moving picture video standard format, the apparatus comprising: first memory means for storing an extension byte of an anterior header of said specified layer; second memory means for storing an extension byte of a current header of said specified layer; means for comparing an extension byte of a current header of said specified layer to the extension byte of said anterior header; and means for transmitting, when the extension byte of said current header is different from the extension byte of said anterior header, the extension byte of said current header and an extension start code indicating the beginning of the extension byte of said current header, and overwriting the extension byte of said current header in said first memory means, and not transmitting, when the extension byte of said current header is the same as the extension byte of said anterior header, the extension byte of said current header and an extension start code indicating the beginning of the extension byte of said current header.