A flexible container with a wall structure comprised of multi-layer, flexible thin films, including a first film layer that is affixed to the wall structure by a releasable adherence and that incorporates a removable promotional piece. The frame of interleaved information bits has a frame start time and a frame end time. In recording moving-picture data to the Memory Stick 31, the CPU 11 records the moving-picture data, in units of data blocks, to a data block of which clusters are all free.