The present invention is intended to provide multiple levels of digest streams
for multimedia contents with small amount of additional storage using a multiple
level digest segment information scheme. In the present invention, a multiple level
digest segment information is contained in the content-based data area of the multimedia
content by representing a level information of each digest segment by multiple
levels in a content-based data area of a multimedia content, describing the digest
level of the digest segment and the time range information of the digest segment
in the digest segment information scheme, and outputting digest segments whose
digest level is less than or equal to requested digest level by decoding, upon
receipt of the digest level of the digest segment.
