| 摘要 |
1. Method for recording or playback of low bitrate data streams, wherein packets of the data stream are recorded in data blocks of constant size and time stamps are used for addressing of the data blocks, the time stamps corresponding to the time duration necessary for a total filling of a data block at the used bitrate, and wherein a maximum time duration is defined corresponding to the total filling of a data block at a minimum bitrate, characterised by that in the case of bitrates below the minimum bitrate empty packets are recorded, which are marked as stuffing packets. 2. Method according to claim 1, wherein the recorded data are organized into Stream Object Units consisting of stream packs (O_S_P) with a stream pack header (P_H) followed by a stream packet (S PES P), wherein a stream packet (S_PES_P) contains further header data (PES_H, S_ID, A_H) and an Application Packet Area (A_P_A), which is filled with a sequence of Application Packets prefixed by an Application Time Stamp (ATS), wherein in the stream pack containing the start of the stuffing packet the Application Packet Area (A_P_A) consists of an Application Time Stamp (ATS) followed by stuffing bytes(Zl) and the subsequent stream packs contain the rest (Z2) of the stuffing packet. 3. Method according to claim 2, wherein a Stuffing Packet starts at the start of the Application Packet Area (A_P_A) of the stream pack (O_S_P) after the stream pack containing genuine Application Packet data. 4. Method according to claim 2 or 3, wherein Stuffing Packets consist of an Application Time Stamp (ATS), followed by as many zero bytes as are needed to fill the Application Data Areas of the remaining packs of the Stream Object Unit. 5. Method according to any of claims 2 to 4, wherein the Application Time Stamp (ATS) of a Stuffing Packet is set as follows: in a Stream Object Unit where at least one pack contains genuine Application Packet data, the Application Time Stamp (ATS) of the Stuffing Packet is set to the Application Time Stamp (ATS) of the Application Packet preceding the Stuffing Packet; in a Stream Object Unit where no real Application Packet data are contained, the Application Time Stamp (ATS) of the Stuffing Packet is set to ATS=SUM_IAPAT(k-1)[(31-MTU_SHFT).. 0]*2<MTU_SHFT>, where SUM_IAPAT is derived from entries of a Mapping List (MAPL) comprising time stamps assigned to the Stream Object Units and MTU_SHFT is a constant derived from the Stream Object Unit size and the maximum allowable bitrate and k is the number of this Stream Object Unit.
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