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.