Apparatus and method for transmitting mpeg-4 data synchronized with mpeg-2 data

• US 20040057457A1
• Filed: 10/28/2003
• Published: 03/25/2004
• Est. Priority Date: 01/13/2001
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Ahn, Chieteuk, Choi, Jin Soo, Kim, Yong Suk, Kim, Jin Woong, Kim, Munchurl, Ahn, Sang-Woo
• Granted Patent: US 7,570,692 B2
• Time in Patent Office: Days
• US Class Current: 370/466
• CPC Class Codes: H04N 21/234309 by transcoding between formats or standards, e.g. from MPEG-2 to MPEG-4 or from Quicktime to Realvideo conversion of standards in analog television systems H04N7/01
• CPC Class Codes: H04N 21/234318 by decomposing into objects, e.g. MPEG-4 objects
• CPC Class Codes: H04N 21/2353 specifically adapted to content descriptors, e.g. coding, compressing or processing of metadata
• CPC Class Codes: H04N 21/23605 Creation or processing of packetized elementary streams [PES]
• CPC Class Codes: H04N 21/23608 Remultiplexing multiplex streams, e.g. involving modifying time stamps or remapping the packet identifiers
• CPC Class Codes: H04N 21/2362 Generation or processing of Service Information [SI]
• 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 21/8193 dedicated tools, e.g. video decoder software or IPMP tool

Abstract

An apparatus and method for transmitting MPEG-4 data synchronized to MPEG-2 data is disclosed. The apparatus for transmitting MPEG-4 data synchronized to MPEG-2 data includes: an object separation unit for extracting MPEG-4 object data from MP4 data, separating meta information from the object data, and generating program information and synchronization information; a conversion unit for converting the MPEG-4 object data to MPEG-4 packets of which data structure is the same as that of MPEG-2 data, based on the program information and synchronization information; and a multiplexing unit for multiplexing the MPEG-4 packets with the MPEG-2 data.

Claims

1. An apparatus for generating and transmitting moving picture expert group-4 (MPEG-4) data synchronized with a MPEG-2 data, comprising:

object separating and information generating means for extracting MPEG-4 object data and meta information related to the MPEG-4 object data from mp4 data which is a storage type of the MPEG-4 data, for analyzing the meta information and for generating program information and synchronization information;

packetizing means for converting the MPEG-4 object data to a MPEG-4 transport stream (TS) packet having a data format of MPEG-2 data by using the meta information, the program information and the synchronization information in order to synchronize the MPEG-4 object data with the MPEG-2 data; and

program multiplexing means for multiplexing the MPEG-4 TS packet and the MPEG-2 data and for generating and outputting a transport stream packet.

2. The apparatus as recited in claim 1, wherein said object separating and information generating means includes:

object separating means for extracting the MPEG-4 object data and the meta information related to the MPEG-4 object data from the mp4 data which is a storage type of the MPEG-4 data, and for analyzing the meta information;

synchronization information generating means for generating the synchronization information by using a composition time stamp/decoding time stamp (CTS/DTS) which is meta information extracted in said object separating means, and a flexible multiplex (FlexMux) packet length information which is a FlexMux packet header information generated in said packetizing means; and

program information generating means for generating the program information by using an elementary stream identifier (ES_ID) which is meta information extracted in said object separating means, and a FluxMuxChannel information which is the FluxMux packet header information generated in said packetizing means.

3. The apparatus as recited in claim 1 or 2, wherein said packetizing means includes:

SL packetizing means for packetizing the MPEG-4 object data and generating a sync layer (SL) packet by using the meta information;

FlexMux packetizing means for packetizing the SL packet and generating a flexible multiplex (FlexMux) packet;

packetizing controlling means for controlling the FlexMux packet to be converted into a packet having a different format from each other according to necessity of synchronization of the FlexMux packet;

PES packetizing means for packetizing the FlexMux packet and generating a PES packet by using the synchronization information;

14496-section packetizing means for packetizing the FlexMux packet and generating a 14496-section packet;

PSI generating means for generating a program specific information (PSI) by using an initial object descriptor (IOS), which is meta information extracted in said object separating and information generating means, and the program information; and

TS packetizing means for packetizing the PES packet, the 14496-section packet and the PSI and generating the MPEG-4 transport stream (TS) packet.

4. A method for generating and transmitting moving picture expert group-4 (MPEG-4) data synchronized with MPEG-2 data, comprising the steps of:

a) extracting MPEG-4 object data and meta information related to the MPEG-4 object data from mp4 data, which is a storage type of the MPEG-4 data and analyzing the meta information;

b) packetizing the MPEG-4 object data by using meta information, thereby generating a primary packetized MPEG-4 object data, a flexible multiple (FlexMux) packet;

c) generating synchronization information and program information by using the meta information and header information of the FlexMux packet;

d) packetizing the FlexMux packet by using the meta information, the synchronization information and the program information, thereby generating a secondary packetized MPEG-4 object data, a MPEG-4 transport stream (TS) packet; and

e) multiplexing the MPEG-4 TS packet and MPEG-2 data and outputting a transport stream (TS) packet.

5. The method as recited in claim 4, wherein said step b) includes the steps of:

b1) packetizing the MPEG-4 object data by using the meta information and generating a sync layer (SL) packet; and

b2) packetizing the SL packet and generating the flexible multiplex (FlexMux) packet.

6. The method as recited in claim 5, wherein the FlexMux packet includes a FlexMux header and a sync layer (SL) packet data unit (PDU).

7. The method as recited in claim 4, wherein said step c) includes the steps of:

c1) generating the synchronization information by using a composition time stamp/decoding time stamp (CTS/DTS), which is meta information extracted at said step a), and FlexMux length information included in the header information of the FlexMux packet; and

c2) generating the program information by using an elementary stream identifier (ES_ID), which is meta information extracted at said step a), and a FlexMuxChannel information included in the header information of the FlexMux packet.

8. The method as recited in claim 7, wherein in the step c1), the CTS/DTS is converted into a program time stamp/decoding time stamp (PTS/DTS).

9. The method as recited in claim 7, wherein said step d) includes the steps of:

d1) generating a control signal for controlling the FlexMux packet according to necessity of synchronization of the FlexMux packet;

d2) generating program specific information (PSI) by using an initial object descriptor (IOD), which is meta information extracted at said step a), and the program information;

d3) packetizing the FlexMux packet by using the synchronization information based on the control signal and generating a packetized elementary stream packet;

d4) packetizing the FlexMux packet based on the control signal and generating a 14496-section packet; and

d5) packetizing the PSI, the PES packet and the 14496-section packet and generating the MPEG-4 transport stream (TS) packet.

10. The method as recited in claim 9, wherein said step d1) includes the step of generating a program map table (PMT), which is a part of program information, by inputting the program information to a FlexMux Channel descriptor (FMC_Descriptor).

11. The method as recited in claim 7, wherein said step e) includes the steps of:

e1) receiving MPEG-2 data and a synchronization initial value through an external interface; and

e2) multiplexing the MPEG-4 TS packet and the MPEG-2 data based on the synchronization initial value and generating the transport stream (TS) packet.

12. The method as recited in claim 11, wherein in said step e2), the MPEG-4 TS packet having a relative time value is synchronized with the MPEG-2 data having an absolute time value by using a multiplex initial value as an insertion point of the MPEG-4 data.

13. A computer readable record medium storing instructions for executing a method for transmitting MPEG-4 data synchronized with MPEG-2 data, the method comprising the steps of:

a) extracting MPEG-4 object data and meta information related to the MPEG-4 object data from mp4 data, which is a storage type of the MPEG-4 data and analyzing the meta information;

b) packetizing the MPEG-4 object data by using meta information, thereby generating a primary packetized MPEG-4 object data, a flexible multiple (FlexMux) packet;

c) generating synchronization information and program information by using the meta information and header information of the FlexMux packet;

d) packetizing the FlexMux packet by using the meta information, the synchronization information and the program information, thereby generating a secondary packetized MPEG-4 object data, a MPEG-4 transport stream (TS) packet; and

e) multiplexing the MPEG-4 TS packet and MPEG-2 data and outputting a transport stream (TS) packet.