Apparatus and method for transmitting hierarchically multimedia data TS to prevent jitter of timing information and for recovering the multimedia data TS

• US 7,415,528 B2
• Filed: 11/04/2004
• Issued: 08/19/2008
• Est. Priority Date: 12/27/2003
• Status: Expired due to Fees

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Kim, Nae-Soo, Choi, Dong-Joon
• Primary Examiner(s): Jacobs; Lashonda T
• Application Number:
  US10/983,081
• Publication Number:
  US 20050141559A1
• Time in Patent Office: 1,384 Days
• Field of Search: 709/231, 709/232, 709/203, 709/217, 709/219, 709/223, 709/224, 725/115, 725/116, 370/516, 370/517
• US Class Current: 709/231
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/70 Media network packetisation
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04N 21/234327 by decomposing into layers, e.g. base layer and one or more enhancement layers
• CPC Class Codes: H04N 21/23614 Multiplexing of additional data and video streams arrangements for simultaneous broadcast of plural pieces of information H04H20/28
• CPC Class Codes: H04N 21/2383 Channel coding or modulation of digital bit-stream, e.g. QPSK modulation arrangements for detecting or preventing errors in the information received by adapting the channel coding H04L1/0009; analogue front ends or means for connecting modulators, demodulators or transceivers to a transmission line H04L27/0002
• 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 21/4305 Synchronising client clock from received content stream, e.g. locking decoder clock with encoder clock, extraction of the PCR packets arrangements for synchronising receiver with transmitter by comparing receiver clock with transmitter clock H04L7/0012; arrangements for synchronising receiver with transmitter wherein the receiver takes measures against momentary loss of synchronisation H04L7/0083
• CPC Class Codes: H04N 21/4348 Demultiplexing of additional data and video streams
• CPC Class Codes: H04N 21/4382 Demodulation or channel decoding, e.g. QPSK demodulation analog front ends or means for connecting modulators, demodulators or transceivers to a transmission line H04L27/0002
• CPC Class Codes: H04N 21/631 Multimode Transmission, e.g. transmitting basic layers and enhancement layers of the content over different transmission paths or transmitting with different error corrections, different keys or with different transmission protocols

Abstract

An apparatus and a method for transmitting multimedia transport stream hierarchically and recovering the multimedia transmission stream are disclosed. The apparatus includes: an input matching unit for dividing the multimedia data transport stream into packets; a sequence number inserting unit for inserting a sequence number to the packet; an error check code (ECC) inserting unit for inserting an ECC to the sequence number inputted packet, to thereby generate a user packet; a layer information storing unit for storing layer information for the user packet; a layer dividing unit for dividing the user packet; a layer storing unit for storing the divided user packet in each layer; and a hierarchical framing and transmitting unit for generating a hierarchical transport frame by combining a predetermined number of the user packets with the layer information, and transmitting the hierarchical frame in a different transmission method for a different layer.

Claims

1. An apparatus for transmitting a multimedia data transport stream (TS) hierarchically in order to prevent jitter of timing information of the multimedia data TS, the apparatus comprising:

an input matching means for dividing the multimedia data transport stream into packets;

a sequence number inserting means for inserting a sequence number to a packet based on a receipt order of the packet, to thereby generate a sequence number inputted packet;

an error check code (ECC) inserting means for inserting an ECC to the sequence number inputted packet, to thereby generate a user packet;

a layer information storing means for storing layer information for the user packet;

a layer dividing means for dividing the user packet based on the layer information;

a layer storing means for storing the divided user packet in each layer; and

a hierarchical framing and transmitting means for generating a hierarchical transport frame by combining a predetermined number of the user packets with the layer information, and transmitting the hierarchical frame in a different transmission method for a different layer.

2. The apparatus as recited in claim 1, wherein the layer dividing means divides the user packet including the timing information as a high priority layer.

3. The apparatus as recited in claim 1, wherein the hierarchical framing and transmitting means generates the transport frame by removing the inserted sequence number in the low priority layer.

4. The apparatus as recited in claim 3, wherein the hierarchical framing and transmitting means removes the inserted sequence number from each high priority layer, inserts a sequence number difference value between neighboring packets and then, generates the packets to the transport frame.

5. An apparatus for recovering multimedia data transport stream (TS) transmitted hierarchically, the apparatus comprising:

a transport frame receiving and user packet extracting means for receiving a hierarchical transport frame transmitted through a transmission channel and extracting a user packet and layer information;

an error packet and layer dividing means for deleting the user packet having an error during the transmission based on an error check code (ECC) and dividing the user packet without an error into a different layer based on the extracted layer information;

a layer storing means for storing an outputted user packet from the an error packet and layer dividing means;

a scheduling means for recovering the location of the user packet stored in the layer storing means in order of the original multimedia data TS based on position information of the user packet;

an error check code and sequence number removing means for removing the ECC and the position information from the recovered user packet, to thereby recover the multimedia data TS; and

an output mapping means for receiving the recovered multimedia data TS and converting a transmission rate to thereby output the multimedia data TS.

6. The apparatus as recited in claim 5, wherein the scheduling means outputs the user packet stored in the layer storing means based on the position information of the user packet in order of the original multimedia data TS to the ECC and sequence number removing means, and a null packet is outputted in the location of the user packet deleted due to an error at the an error packet and layer dividing means or the lost user packet instead thereof.

7. The apparatus as recited in claim 6, wherein the position information is a difference value between the sequence number of the user packet and the neighboring user packets.

8. The apparatus as recited in claim 7, wherein the output mapping means converts the multimedia data TS based on a time stamp when there is the time stamp in the multimedia data TS.

9. A method for hierarchically transmitting a multimedia data transport stream (TS) in order to prevent jitter of timing information of the multimedia data TS, the method comprising the steps of:

a) receiving a multimedia data TS from external device and dividing the multimedia data TS into packets;

b) inserting a sequence number to the divided packet based on a receipt order of the packet and inserting an error check code (ECC) to the sequence number inputted packet, to thereby generate a user packet;

c) dividing the ECC and sequence number inserted user packet based on layer information provided by a user, to thereby store the divided user packet hierarchically; and

d) generating a hierarchical transport frame by combining a predetermined number of the user packets with the layer information, and transmitting the hierarchical frame in a different transmission method for a different layer.

10. The method as recited in claim 9, wherein in the step c), the user packet is divided hierarchically based on the layer information provided by the user and the user packet having the timing information is divided as a high priority layer.

11. The method as recited in claim 10, wherein in the step c), the inserted sequence number is removed from low priority layer packets to thereby generate transport frame.

12. The method as recited in claim 11, wherein in the step d), the inserted sequence number is removed from a priority layer packet and a difference value of the sequence number between neighboring user packets is inserted to thereby generate the transport frame.

13. A method for recovering a multimedia data transport stream (TS) transmitted hierarchically, the method comprising the steps of:

a) receiving a hierarchical transport frame transmitted through a transmission channel and extracting a user packet and layer information from the received transport frame;

b) deleting the user packet having an error during the transmission based on an error check code (ECC) and dividing the user packet without an error into a difference layer based on the extracted layer information to thereby storing hierarchically according to layers;

c) recovering a location of the stored user packets in order of the original multimedia data TS by scheduling based on the position information in the user packet;

d) removing the ECC and the position information from the recovered user packet, to thereby recover the multimedia data TS; and

e) converting a transmission rate of the recovered multimedia data TS to thereby output the multimedia data TS.

14. The method as recited in claim 13, wherein in the step c), the user packet is recovered based on the position information of the user packet in order of the original multimedia data TS, and a null packet is outputted in the location of the user packet deleted due to an error at the an error packet and layer dividing means or the lost user packet instead thereof.

15. The method as recited in claim 14, wherein the position information is a difference value between the sequence number of the user packet and the neighboring user packets.