Patent ID: 6839504

Claim:
An information recording medium for recording a real-time file containing real-time data in such a manner that the real-time data is continuously reproducible by a playback reference model, the real-time data comprising at least one of video data and audio data, wherein the playback reference model includes: a pickup for reading the real-time data from the information recording medium; a buffer memory for temporarily storing the real-time data read by the pickup; and a decoder module for reading the real-time data from the buffer memory for processing, wherein the information recording medium comprises a volume space for at least recording in sectors a file comprising data and file management information for managing the file; the real-time data is recorded in N real-time extents (where N is an integer which is equal to or greater than 2) each of which is allocated with logically contiguous sectors within the volume space; and an (i+1)th real-time extent (where i is an integer which satisfies 1≦i<N) among the real-time extents is positioned at a position satisfying a real-time reproduction condition defined as: B ( i )= B ( i −1)+ D ( i )− V out× T ( i )≧0, wherein: T(i) represents a time required for the pickup to access from an end of an ith real-time extent to a beginning of the (i+1)th real-time extent; B(i) represents an amount of data having been stored in the buffer memory when the pickup accesses the beginning of the (i+1)th real-time extent, assuming that B( 0 )=0, D(i) represents an increase in the amount of data having been stored in the buffer memory responsive to the pickup reading the data from the ith real-time extent, such that D(i)=(Vin−Vout)×S(i)/Vin, wherein D(i) is corrected at least to a value equal to or smaller than M−B(i−1) when B(i−1)+D(i)>M, where M represents a size of the buffer memory; Vout represents a data transfer rate when the data is transferred from the buffer memory to the decoder module; Vin represents a data transfer rate when the data is read from each of the real-time extents by the pickup and transferred to the buffer memory; and S(i) represents a data size of the ith real-time extent.