A storage medium format for a storage medium containing packetized data programs includes packet identifiers (PIDs) that identify individual packetized datastreams constituting a program. The data format facilitates the association and assembly of the packetized datastreams of the program by a decoder, independent of PID de-mapping data. The PIDs include a base PID for identifying one datastream and a second PID of predetermined offset value to the base PID for identifying a second datastream. Corresponding packetized datastreams that constitute different programs are given the same PID. The storage medium format may also include program specific information (PSI) suitable for use in recovering data content of a program. The PSI includes an MPEG-like program map table (PMT) and an MPEG-like program association table (PAT) and incorporates a parameter suitable for commanding a decoder to apply the PSI in decoding the program irrespective of previous PSI content. In addition, the PSI may incorporate a version number that is varied between successive occurrences of the PSI irrespective of substantive change in PSI content. One or more private data elements may also be included in the PMT to describe the program.