Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
  • H04N21/60—Network structure or processes for video distribution between server and client or between remote clients; Control signalling between clients, server and network components; Transmission of management data between server and client, e.g. sending from server to client commands for recording incoming content stream; Communication details between server and client 
  • H04N21/63—Control signaling related to video distribution between client, server and network components; Network processes for video distribution between server and clients or between remote clients, e.g. transmitting basic layer and enhancement layers over different transmission paths, setting up a peer-to-peer communication via Internet between remote STB's; Communication protocols; Addressing
  • H04N21/643—Communication protocols
  • H04N21/6437—Real-time Transport Protocol [RTP]
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N7/00—Television systems
  • H04N7/12—Systems in which the television signal is transmitted via one channel or a plurality of parallel channels, the bandwidth of each channel being less than the bandwidth of the television signal
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
  • H04N21/20—Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
  • H04N21/23—Processing of content or additional data; Elementary server operations; Server middleware
  • H04N21/234—Processing of video elementary streams, e.g. splicing of video streams or manipulating encoded video stream scene graphs
  • H04N21/2343—Processing of video elementary streams, e.g. splicing of video streams or manipulating encoded video stream scene graphs involving reformatting operations of video signals for distribution or compliance with end-user requests or end-user device requirements
  • H04N21/234318—Processing of video elementary streams, e.g. splicing of video streams or manipulating encoded video stream scene graphs involving reformatting operations of video signals for distribution or compliance with end-user requests or end-user device requirements by decomposing into objects, e.g. MPEG-4 objects
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
  • H04N21/20—Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
  • H04N21/23—Processing of content or additional data; Elementary server operations; Server middleware
  • H04N21/236—Assembling of a multiplex stream, e.g. transport stream, by combining a video stream with other content or additional data, e.g. inserting a URL [Uniform Resource Locator] into a video stream, multiplexing software data into a video stream; Remultiplexing of multiplex streams; Insertion of stuffing bits into the multiplex stream, e.g. to obtain a constant bit-rate; Assembling of a packetised elementary stream
  • H04N21/2365—Multiplexing of several video streams
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
  • H04N21/20—Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
  • H04N21/23—Processing of content or additional data; Elementary server operations; Server middleware
  • H04N21/238—Interfacing the downstream path of the transmission network, e.g. adapting the transmission rate of a video stream to network bandwidth; Processing of multiplex streams
  • H04N21/2381—Adapting the multiplex stream to a specific network, e.g. an Internet Protocol [IP] network
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
  • H04N21/20—Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
  • H04N21/23—Processing of content or additional data; Elementary server operations; Server middleware
  • H04N21/242—Synchronization processes, e.g. processing of PCR [Program Clock References]
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
  • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
  • H04N21/41—Structure of client; Structure of client peripherals
  • H04N21/426—Internal components of the client ; Characteristics thereof
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
  • H04N21/60—Network structure or processes for video distribution between server and client or between remote clients; Control signalling between clients, server and network components; Transmission of management data between server and client, e.g. sending from server to client commands for recording incoming content stream; Communication details between server and client 
  • H04N21/61—Network physical structure; Signal processing
  • H04N21/6106—Network physical structure; Signal processing specially adapted to the downstream path of the transmission network
  • H04N21/6112—Network physical structure; Signal processing specially adapted to the downstream path of the transmission network involving terrestrial transmission, e.g. DVB-T

Definitions

• the invention relates generally to digital video broadcasting, and more particularly to the application of advanced coding methods for digital video signals.
• HDTV High definition television
• MPEG-4 Motion Picture Experts Group
• MPEG-4 supports low bit rate channels for transmitting signals to devices with small display devices.
• MPEG-2 is significantly less efficient for sending transmissions with low bit rates.
• MPEG-4 part 10 coding it is possible to send quarter- VGA resolution with high quality at 400 Kbps. Since quarter- VGA resolution is approximately VCR quality, 50 such channels could be sent on one ATSC 6 MHz channel.
• the ATSC standard for digital television broadcast specifies a Data Channel in addition to the normal audio and video channels.
• a methodology is provided for using the ATSC Data Channel to broadcast MPEG-4 video streams, for which a new video service can be created.
• the MPEG-4 streams can be encapsulated into MPEG-2 PES (Packetized Elementary Stream) packets or directly into MPEG-2 transport packets. These mechanisms enable the synchronous broadcast of MPEG-4 streams for an ATSC digital TV system without a change to the ATSC standard when data casting.
• An embodiment of the invention uses an ATSC terrestrial transmission system for broadcasting MPEG-4 video and audio streams for mobile and non-mobile receivers.
• Figure 1 is a high-level schematic depiction of an ATSC broadcast system
• Figure 5 provides a schematic depiction of a method for encapsulating MPEG-4 data into packets of an ATSC transport stream according to a third embodiment of the invention.
• HDTV and other advanced television services are provided pursuant to standards promulgated by the Advanced Television Systems Committee (ASTC), the basic such standard being ASTC Standard A/53, ASTC Digital Television Standard.
• ASTC Advanced Television Systems Committee
• MPEG-2 Motion Picture Experts Group
• ISO/TEC 13818 International Standard ISO/TEC 13818, Information Technology - Generic Coding of Moving Pictures and Associated Audio Information.
• FIG. 1 A high-level schematic illustration of the main subsystems of the ATSC advanced television systems is shown in Figure 1.
• system encompasses an Application (video/audio) Coding and Compression subsystem 101, a Service Multiplex And Transport subsystem 102 and an RF/Transmission subsystem 103.
• the application coding and compression subsystem includes Video Coding and Compression 110 and Audio Coding and Compression 112, which are provided pursuant to the ATSC A/53 standard.
• the video application is based on the MPEG-2 standard and that the particulars of these input functions are well known to those skilled in the art, no further discussion of the ASTC video and audio coding and compression functions is needed here.
• a Data Channel 114 is also provided as an input to the system in accordance with ATSC Standard A 90, ATSC Data Broadcast Standard. Although some form of encoding and/or compression may be applied for data input to the system using the Data Channel, such encoding/compression is outside the scope of the Standard, and is accordingly not shown in the figure. Operation of the Data Channel will be described in more detail below.
• the RF/Transmission subsystem (103), which includes Channel Coding function 130, Modulation function 132 and Transmission Media 134, carries out functions well known to those skilled in the art and need not be further described here.
• An output signal from the RF/Transmission subsystem (103), which includes Channel Coding function 130, Modulation function 132 and Transmission Media 134, carries out functions well known to those skilled in the art and need not be further described here.
• the ATSC transport function also follows the MPEG-2 system coding specification wherein the elementary streams may be multiplexed into either a Program Stream or a Transport Stream.
• a Program Stream results from combining one or more streams of PES packets, having a common time base, into a single stream.
• a Transport Stream combines one or more programs with one or more independent time bases into a single stream.
• Transport Stream is also designed for use in environments where errors are likely, such as transmission in lossy or noisy media.
• Data transmitted via the ATSC Data Channel 114 (pursuant to ATSC Standard A/90) is encapsulated into the payload of MPEG-2 Transport Stream packets.
• Various data transmission methodologies are contemplated by the A/90 Standard, including Synchronous Data Streaming and Data Piping.
• Synchronous Data Streaming is defined in the Standard as the streaming of data with timing requirements, in the sense that the data and clock can be regenerated at the receiver into a synchronous data stream.
• Synchronous data streams have no strong timing association with other data streams and are carried in PES packets.
• Data Piping is defined by the standard as a mechanism for delivery of arbitrary user-defined data inside an MPEG-2 Transport Stream.
• the Service Multiplex function 120 includes both an MPEG-2 Service Multiplex 121, which operates to carry out the typical prior art MPEG-2 processing, and a Data Service Multiplex 124, which receives a stream of MPEG-4 VOPs from the MPEG-4 video encoder 115.
• the Service Multiplex 124 uses either PES packets or RTP (Real Time Protocol) packets to encapsulate the MPEG-4 VOPs and the Audio access units into separate PES or RTP streams. The process of such packetization of MPEG-4 units according to the method of the invention is described in detail below.
• the output of Data Service Multiplex 124 is provided to Transport Stream Packetizer
• the PES header contains a presentation time stamp (PTS) relative to the program clock reference (PCR) in the transport header. This PTS synchronizes the MPEG-4 video stream to system time.
• the audio PES packets also include an audio PTS relative to the transport layer PCR. Therefore, the audio and video are synchronized by having the same reference system time (the transport layer PCR).
• the synchronous data header required for this mode of the ATSC data broadcast standard is included in every PES header (once per VOP).
• the synchronous data includes an 8 bit extension for the PTS field, and an optional data rate parameter.
• ATSC Data Piping uses a mechanism that allows any type of data to be encapsulated in MPEG-2 transport packets without any restriction.
• the absence of restrictions allows for Data Piping to use more efficient methods for encapsulating MPEG-4 bit streams than using Synchronous Data Streaming.
• a presentation time stamp (PTS) is, however, still used for every video frame and every audio frame.
• an RTP based protocol is preferably used in this embodiment - i.e., each MPEG-4 VOP uses an RTP header with a time stamp.
• the RTP header contains a 32 bit time stamp parameter.
• each transport packet is constituted by a Transport Header 422-i and a Transport Payload 424-i (again, where i represents a packet index number).
• a pointer can be defined as the first byte of the transport payload, or an extension to the RTP header could include an optional pointer.
• Other such approaches will, however, be apparent to those skilled in the art, and all such approaches are intended to be encompassed within the scope of the invention.

Landscapes

• Engineering & Computer Science (AREA)
• Multimedia (AREA)
• Signal Processing (AREA)
• Compression Or Coding Systems Of Tv Signals (AREA)
• Television Systems (AREA)
• Compression, Expansion, Code Conversion, And Decoders (AREA)

Applications Claiming Priority (3)

Publications (2)

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Family Applications (1)

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Family Cites Families (2)

• 2002
  • 2002-07-19 WO PCT/US2002/023031 patent/WO2003010975A1/en not_active Ceased
  • 2002-07-19 CN CNA02817514XA patent/CN1552159A/zh active Pending
  • 2002-07-19 MX MXPA04000744A patent/MXPA04000744A/es not_active Application Discontinuation
  • 2002-07-19 EP EP02750184A patent/EP1421796A4/en not_active Withdrawn
  • 2002-07-19 JP JP2003516227A patent/JP2004537226A/ja not_active Ceased
  • 2002-07-19 KR KR10-2004-7000995A patent/KR20040017830A/ko not_active Ceased
  • 2002-07-19 BR BR0211406-2A patent/BR0211406A/pt not_active IP Right Cessation

Non-Patent Citations (8)

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