System and method for improved multi-stream multimedia transmission and processing

• US 20020184637A1
• Filed: 05/30/2001
• Published: 12/05/2002
• Est. Priority Date: 05/30/2001
• Status: Active Grant

• Current Assignee: ARRIS Enterprises LLC (CommScope Holding Company, Inc.)
• Original Assignee: Digco BV
• Inventors: Perlman, Stephen G.
• Granted Patent: US 7,093,277 B2
• Time in Patent Office: Days
• US Class Current: 725/87
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 63/068 using time-dependent keys, e.g. periodically changing keys cryptographic mechanisms or cryptographic arrangements for controlling usage of secret information H04L9/088
• CPC Class Codes: H04N 21/4147 PVR [Personal Video Recorder] H04N5/76 takes precedence ; arrangements for broadcast with accumulation-type receivers H04H20/40
• CPC Class Codes: H04N 21/426 Internal components of the client ; Characteristics thereof H04N5/44 takes precedence
• CPC Class Codes: H04N 21/4263 involving specific tuning arrangements, e.g. two tuners
• CPC Class Codes: H04N 21/4334 Recording operations recording of a television signal H04N5/76; arrangements for recording or accumulating broadcast information or broadcast-related information H04H60/27
• CPC Class Codes: H04N 21/434 Disassembling of a multiplex stream, e.g. demultiplexing audio and video streams, extraction of additional data from a video stream; Remultiplexing of multiplex streams; Extraction or processing of SI; Disassembling of packetised elementary stream demultiplexing of data packets for data networks, e.g. RTP/UDP H04L65/00
• CPC Class Codes: H04N 21/4383 Accessing a communication channel
• CPC Class Codes: H04N 21/4384 involving operations to reduce the access time, e.g. fast-tuning for reducing channel switching latency
• CPC Class Codes: H04N 21/4623 Processing of entitlement messages, e.g. ECM [Entitlement Control Message] or EMM [Entitlement Management Message] arrangements for conditional access to broadcast information or to broadcast-related services H04H60/14
• CPC Class Codes: H04N 21/47 End-user applications
• CPC Class Codes: H04N 21/4821 using a grid, e.g. sorted out by channel and broadcast time
• CPC Class Codes: H04N 21/8455 involving pointers to the content, e.g. pointers to the I-frames of the video stream
• CPC Class Codes: H04N 21/8586 by using a URL processing chained hypermedia data for information retrieval G06F16/94; information retrieval from the Internet by using URLs G06F16/955; URL in broadcast information H04H20/93; Web-based protocols H04L67/02
• CPC Class Codes: H04N 5/76 Television signal recording
• CPC Class Codes: H04N 9/7921 for more than one processing mode
• CPC Class Codes: H04N 9/8042 involving data reduction

Abstract

A method for efficiently transmitting several multimedia streams to one or more multimedia receivers is disclosed comprising: defining a minimum acceptable time for rendering a multimedia stream to a user when the user selects a particular stream; defining a packet size for packets containing data for each multimedia stream, the packet size defined based on one or more performance characteristics of mass storage devices on the one or more multimedia receivers; concurrently transmitting the packets for each multimedia stream to the one or more multimedia receivers; continually storing the multimedia streams on the mass storage devices; and playing back the multimedia content from the mass storage devices responsive to a user tuning to a particular multimedia stream when a delay greater than the minimum acceptable time would otherwise result waiting for a next packet containing data for the particular multimedia stream to arrive.

Claims

1. A method for efficiently transmitting several multimedia streams to one or more multimedia receivers comprising:

defining a minimum acceptable time for rendering a multimedia stream to a user when said user selects a particular stream;

defining a packet size for packets containing data for each multimedia stream, said packet size defined based on one or more performance characteristics of mass storage devices on said one or more multimedia receivers;

concurrently transmitting said packets for each multimedia stream to said one or more multimedia receivers;

continually storing said multimedia streams on said mass storage devices; and

playing back said multimedia content from said mass storage devices responsive to a user tuning to a particular multimedia stream when a delay greater than said minimum acceptable time would otherwise result waiting for a next packet containing data for said particular multimedia stream to arrive.

2. The method as in claim 1 wherein at least one of said performance characteristics is the seek time capability of said mass storage devices.

3. The method as in claim 1 wherein said defined packet size is further based a number of said packets which said multimedia receivers are capable of buffering in memory before storing said packets to said mass storage devices.

4. The method as in claim 1 wherein relatively larger packet sizes are selected for a relatively smaller number of packets capable of being buffered in memory.

5. The method as in claim 1 wherein said defined packet size is greater than 188 bytes.

6. The method as in claim 1 further comprising:

simulcasting said multimedia streams using packets of a second defined packet size, said second defined packet size adapted to be processed by one or more legacy multimedia receivers.

11. The method as in claim 1 further comprising:

simulcasting said plurality of multimedia streams using packets of a second defined packet size, said second defined packet size adapted to be processed by one or more legacy multimedia receivers.

13. The method as in claim 12 wherein said single packet size is 100 Kbytes.

14. The method as in claim 12 further comprising:

determining said single packet size based on a bitrate at Which said multimedia content is transmitted.

15. The method as in claim 12 further comprising:

simulcasting one or more streams in which said multimedia content contained in said plurality of PID packets is not combined into a single packet of said specified size.

16. The method as in claim 12 wherein said predetermined period of time is less than 0.25 seconds.

18. The method as in claim 17 wherein said alternate frequency range is larger than said first frequency range.

19. The method as in claim 18 wherein said alternate frequency range is 30 MHz and said first frequency range is 6 MHz.

20. The method as in claim 17 wherein said first plurality of channels transmitted in said first plurality of frequency blocks are encrypted using a first encryption technique and said second plurality of channels transmitted in said alternate frequency blocks are encrypted using a second encryption technique.

21. The method as in claim 20 wherein said first encryption technique is standard conditional access encryption and said second encryption technique is DES encryption.

22. The method as in claim 17 wherein said first plurality of channels transmitted in said first plurality of frequency blocks are compressed using a first compression technique and said second plurality of channels transmitted in said alternate frequency blocks are compressed using a second compression technique.

23. The method as in claim 22 wherein said first compression technique is MPEG-2 and said second compression technique is MPEG-4.

24. The method as in claim 17 wherein said first plurality of channels are transmitted in said first plurality of frequency blocks using a first PID packet size and said second plurality of channels are transmitted in said alternate frequency blocks using a second PID packet size.

25. The method as in claim 24 wherein said first PID packet size is 188 bytes and said second PID packet size is 100 Kbytes.

27. The method as in claim 26 wherein said multimedia receiver comprises a buffer memory smaller than that required to concurrently buffer at least one of said plurality of packets for each of said plurality of multimedia streams.

28. The method as in claim 27 further comprising:

buffering said data for said plurality of multimedia streams on a mass storage device on said multimedia receiver.

29. The method as in claim 28 further comprising:

playing back one of said multimedia streams from said hard drive responsive to a user tuning to said stream when a delay greater than said required channel tuning speed would otherwise result if said multimedia stream were not played back from said hard drive.

7. A method comprising:

transmitting a plurality of packets of a specified size to a plurality of multimedia receivers, each of said plurality of packets containing content for one of a plurality of multimedia streams, wherein a delay in time between two successive packets containing data for one of said multimedia streams is greater than a minimum defined speed for displaying said one multimedia stream for an end user.

8. The method as in claim 7 further comprising:

playing back said one multimedia stream to a user from a mass storage device on said user'"'"'s multimedia receiver responsive to said user selecting said stream for playback.

9. The method as in claim 8 further comprising:

selecting said specified size of said plurality of packets based on one or more performance characteristics of said mass storage device.

10. The method as in claim 9 wherein one of said performance characteristics are seek time specifications of said mass storage device.

12. A method for reducing buffering requirements of a multi-stream multimedia receiver:

for each multimedia stream, combining multimedia content contained in a plurality of PID packets into a single packet of a specified size;

storing said multimedia content on a hard drive at said multimedia receiver; and

playing back said multimedia content from said hard drive responsive to a user tuning to a stream carrying said multimedia content when a delay greater than a required channel tuning speed would otherwise result if said multimedia content were not played back from said hard drive.

17. A method comprising:

transmitting a first plurality of channels within a first plurality of frequency blocks having a first frequency range, said first frequency range being the range to which a legacy group of multimedia receivers are capable of tuning; and

simulcasting said first plurality of channels within one or more alternate frequency blocks having an alternate frequency range, said alternate frequency range being the range to which an alternate group of multimedia receivers are capable of tuning.

26. A method comprising:

transmitting a plurality of packets with each packet in said plurality containing data for one of a plurality of multimedia streams, wherein packets containing data for at least one particular multimedia stream of said plurality are separated in said transmission by an amount of time greater than a required channel tuning speed at a multimedia receiver to which said plurality of packets are transmitted.