Patent ID: 7130525

Claim:
A data access position locating method for locating access positions in a data recording medium in which a data sequence of a continuous recording period in a first data stream having video data is managed as a base unit of data, comprising the steps of: based on presentation time information as to a specified piece of video data and reference time information related to reference position information of a target base unit of data, determining a relative time from the reference time information to the presentation time information; identifying a target subunit of data including the specified piece of video data by operation based on the relative time as to the specified piece of video data and playback time of a subunit of data; and identifying start position information of the target subunit of data from relative distance information stored beforehand in a management information area, wherein the base unit of data comprises a plurality of subunits of data, each having an identical playback time within a single base unit of data, and for each of the base units of data, reference position information that is start position information of the base unit of data and relative distance information from the reference position information to start position information of each of the subunits of data in the base unit of data are stored beforehand in the management information area of a recording medium.