Apparatus for encoding and decoding header data in picture signal transmission

An encoding apparatus for encoding a video signal, comprising:

• an encoding unit for performing an encoding process on the video signal to generate a bit stream which is compatible with MPEG 1 moving picture video standard;
• and
• a controlling unit for controlling the encoding process so as to generate the bit stream which includes, a picture start code indicating a start point of a picture layer in a previous picture header, an extension start code indicating the beginning of extension data added when a picture header includes control data that is newly added in MPEG 2 standard format in the previous header, the extension data in the previous header, and the picture start code in a current picture header, and does not include the extension start code in the current picture header and the extension data in the current picture header.

A picture decoding method, executed by a processor, for decoding a bit stream, the hit stream being compatible with MPEG1 standard, the method comprising the steps of:

• detecting, in a current picture header of the bit stream, the presence of an extension start code indicating the beginning of extension data added in a picture header of the bit stream when the picture header includes control data that is newly added in MPEG2 standard;
• and
• decoding the bit stream in a current picture layer by using a picture start code indicating a start point of a picture layer in the current picture header of the bit stream and the extension data of a previous picture header of the bit stream in case the presence of the extension start code is not detected in the current picture header of the bit stream and by using the picture start code of the current picture header of the bit stream and the extension data of the current picture header of the bit stream in case the presence of the extension start code is detected in the current picture header.