Patent ID: 8094537

Claim:
A read-only information storage medium for use with a reproducing apparatus, the read-only information storage medium comprising: a plurality of data areas each comprising a plurality of data frames, each of the data frames comprising corresponding sync data of a plurality of sync data for the plurality of data frames; and an additional data area located between two of the data areas and comprising: a first additional data frame comprising first sync data; and a second additional data frame comprising second sync data; wherein the first sync data is different from the second sync data; the first sync data is different from each of the plurality of sync data of the data frames; the second sync data is different from each of the plurality of sync data of the data frames; the first sync data and the second sync data enable the apparatus to identify the additional data area from the data areas when the read-only information storage medium is used with the apparatus; a size of the first additional data frame is identical to a size of the second additional data frame; and a size and a location of the additional data area are selected to provide consistency with a recordable information storage medium having a format that is different from a format of the read-only information storage medium.