apparatus and method for segmentation and time synchronization of the transmission of multimedia data

• US 5,537,408 A
• Filed: 06/05/1995
• Issued: 07/16/1996
• Est. Priority Date: 02/03/1995
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Leichty, Phillip L., Sendelbach, Lee A., Lynch, Jeffrey J., Byrn, Jonathan W., Delp, Gary S., Plotz, Kevin G., Slane, Albert A., Branstad, Mark W.
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): Blum, Russell W.
• Application Number:
  US08/463,207
• Time in Patent Office: 407 Days
• Field of Search: 370/60, 370/60.1, 370/79, 370/85.6, 370/94.1, 370/94.2, 370/100.1, 370/108, 379/93, 379/94, 379/96, 348/13, 348/17, 348/461, 348/464, 348/467, 348/473, 348/500, 348/512, 348/518
• US Class Current: 370/473
• CPC Class Codes: H04J 3/0632 Synchronisation of packets and cells, e.g. transmission of voice via a packet network, circuit emulation service [CES] queuing arrangements in packet switching elements H04L49/90; synchronising systems for the synchronous transmission of a pulse code modulated video signal with one or more other pulse code modulated signals H04N7/56
• CPC Class Codes: H04L 2012/5616 Terminal equipment, e.g. codecs, synch.
• CPC Class Codes: H04L 2012/565 Sequence integrity
• CPC Class Codes: H04L 2012/5652 Cell construction, e.g. including header, packetisation, depacketisation, assembly, reassembly
• CPC Class Codes: H04L 2012/5664 Support of Video, e.g. MPEG
• CPC Class Codes: H04L 2012/5674 Synchronisation, timing recovery or alignment
• CPC Class Codes: H04L 2012/5679 Arbitration or scheduling
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/70 Media network packetisation
• CPC Class Codes: H04L 69/324 in the data link layer [OSI layer 2], e.g. HDLC
• CPC Class Codes: H04L 69/326 in the transport layer [OSI layer 4] H04L69/16 takes precedence
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04N 21/234318 by decomposing into objects, e.g. MPEG-4 objects
• CPC Class Codes: H04N 21/2368 Multiplexing of audio and video streams
• CPC Class Codes: H04N 21/2381 Adapting the multiplex stream to a specific network, e.g. an Internet Protocol [IP] network transmission of MPEG streams over ATM H04L12/5601
• CPC Class Codes: H04N 21/242 Synchronization processes, e.g. processing of PCR [Program Clock References] arrangements for synchronising broadcast or distribution via plural systems in broadcast distribution systems H04H20/18
• CPC Class Codes: H04N 21/2543 Billing , e.g. for subscription services payment schemes, architectures or protocols G06Q20/00; e-commerce G06Q30/00; arrangements for billing for the use of broadcast information or broadcast-related information H04H60/21
• CPC Class Codes: H04N 21/262 Content or additional data distribution scheduling, e.g. sending additional data at off-peak times, updating software modules, calculating the carousel transmission frequency, delaying a video stream transmission, generating play-lists scheduling strategies for dispatcher in multiprogramming arrangements G06F9/4881; arrangements for scheduling broadcast services or broadcast-related services H04H60/06; flow control in packet networks H04L47/10; establishing a time schedule or organising the servicing of application requests H04L67/62
• CPC Class Codes: H04N 21/26208 the scheduling operation being performed under constraints
• CPC Class Codes: H04N 21/43072 of multiple content streams on the same device
• CPC Class Codes: H04N 21/4341 : Demultiplexing of audio and video streams
• CPC Class Codes: H04N 21/4363 : Adapting the video stream to a specific local network, e.g. a Bluetooth® network
• CPC Class Codes: H04N 21/4381 : Recovering the multiplex stream from a specific network, e.g. recovering MPEG packets from ATM cells transmission of MPEG streams over ATM H04L12/5601
• CPC Class Codes: H04N 21/47202 : for requesting content on demand, e.g. video on demand
• CPC Class Codes: H04N 21/64307 : ATM
• CPC Class Codes: H04N 21/8456 : by decomposing the content in the time domain, e.g. in time segments
• CPC Class Codes: H04N 21/8547 : involving timestamps for synchronizing content
• CPC Class Codes: H04Q 11/0478 : Provisions for broadband connections

Abstract

Method and apparatus are provided for transmitting a stream of multimedia digital data over a distribution communications network. A multimedia stream server segments the multimedia digital data stream into data blocks on a first boundary and a second boundary. The first boundary is a set number of transport system data packets and the second boundary is a transport system data packet including a timestamp. A scheduler schedules the segmented data blocks for transmission. The multimedia stream server decodes the segmented data blocks to locate the timestamps and matches the transmission of the located timestamp data block with a time value indicated by the timestamp. The set number of transport system data packets can be determined at connection setup and is not a predetermined value for all sessions. At the receiver, batch processing of received multimedia data can be provided.

Claims

1. A method for segmenting a multimedia data stream for transmission over a distribution communications network, said multimedia data stream including sequential transport system (TS) packets with program clock references (PCRs) at a selected time interval, said method comprising the steps of:

receiving the multimedia digital data stream;

decoding said TS packets to identify the program clock references (PCRs);

identifying a selected number N of TS packets;

encapsulating said multimedia digital data stream into frames responsive to both said identified selected number N of TS packets and said identified PCR; and

identifying said selected number N at a connection setup for the multimedia data stream.

3. A method for segmenting a multimedia data stream as recited in claim 1 wherein said step of encapsulating said multimedia digital data stream into frames responsive to both said identified selected number N of TS packets and said identified PCR includes the step of transforming said multimedia digital data stream TS packets directly into fixed size Asynchronous Transfer Mode (ATM) cells;

said ATM cells being transmitted over the distribution communications network and being reassembled into said multimedia digital data stream frames by a decoder/receiver coupled to the network.

2. A method for segmenting a multimedia data stream for transmission over a distribution communications network, said multimedia data stream including sequential transport system (TS) packets with program clock references (PCRs) at a selected time interval, said method comprising the steps of:

receiving the multimedia digital data stream;

decoding said TS packets to identify the program clock references (PCRs);

identifying a selected number N of TS packets;

encapsulating said multimedia digital data stream into frames responsive to both said identified selected number N of TS packets and said identified PCR; and

wherein said step of encapsulating said multimedia digital data stream into frames responsive to both said identified selected number N of TS packets and said identified PCR provides sequential multimedia digital data stream frames, each frame including one to said selected number N of TS packets and wherein an identified TS packet containing said identified PCR is the last packet in said frame.

4. Apparatus for segmenting a multimedia data stream for transmission over a distribution communications network, said multimedia data stream including sequential transport system (TS) packets with embedded program clock references (PCRs) at a selected time interval, comprising:

means for receiving the multimedia digital data stream;

means for decoding said TS packets to identify the program clock references (PCRs);

means for identifying a selected number N of TS packets;

means for encapsulating said multimedia digital data stream into frames responsive to both said identified selected number N of TS packets and said identified PCR; and

data supply processor means for supplying the multimedia digital data stream to said receiving means and notification means for requesting data from said data supply processor means.

5. Apparatus for segmenting a multimedia data stream as recited in claim 4 wherein said means for encapsulating said multimedia digital data stream into frames responsive to both said identified selected number N of TS packets and said identified PCR includes means for transforming said multimedia digital data stream TS packets directly into fixed size Asynchronous Transfer Mode (ATM) cells;

said ATM cells being transmitted over the distribution communications network and being reassembled into said multimedia digital data stream frames by a decoder/receiver coupled to the network.