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WO2002031670A1 - Procede et systeme de transmission de qualite de service selectionnable par le destinataire sur des reseaux - Google Patents

Procede et systeme de transmission de qualite de service selectionnable par le destinataire sur des reseaux Download PDF

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Publication number
WO2002031670A1
WO2002031670A1 PCT/US2001/031861 US0131861W WO0231670A1 WO 2002031670 A1 WO2002031670 A1 WO 2002031670A1 US 0131861 W US0131861 W US 0131861W WO 0231670 A1 WO0231670 A1 WO 0231670A1
Authority
WO
WIPO (PCT)
Prior art keywords
data
bands
channels
different
frames
Prior art date
Application number
PCT/US2001/031861
Other languages
English (en)
Other versions
WO2002031670A8 (fr
Inventor
Gilbert Irving Cardwell
Original Assignee
Teraglobal Communications Corp.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Teraglobal Communications Corp. filed Critical Teraglobal Communications Corp.
Publication of WO2002031670A1 publication Critical patent/WO2002031670A1/fr
Publication of WO2002031670A8 publication Critical patent/WO2002031670A8/fr

Links

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]
    • H04N21/20—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
    • H04N21/234327—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 layers, e.g. base layer and one or more enhancement layers
    • 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
    • H04N21/24—Monitoring of processes or resources, e.g. monitoring of server load, available bandwidth, upstream requests
    • H04N21/2402—Monitoring of the downstream path of the transmission network, e.g. bandwidth available
    • 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
    • H04N21/25—Management operations performed by the server for facilitating the content distribution or administrating data related to end-users or client devices, e.g. end-user or client device authentication, learning user preferences for recommending movies
    • H04N21/266—Channel or content management, e.g. generation and management of keys and entitlement messages in a conditional access system, merging a VOD unicast channel into a multicast channel
    • H04N21/2662—Controlling the complexity of the video stream, e.g. by scaling the resolution or bitrate of the video stream based on the client capabilities
    • 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
    • H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
    • H04N21/44—Processing of video elementary streams, e.g. splicing a video clip retrieved from local storage with an incoming video stream or rendering scenes according to encoded video stream scene graphs
    • H04N21/4402—Processing of video elementary streams, e.g. splicing a video clip retrieved from local storage with an incoming video stream or rendering scenes according to encoded video stream scene graphs involving reformatting operations of video signals for household redistribution, storage or real-time display
    • H04N21/440227—Processing of video elementary streams, e.g. splicing a video clip retrieved from local storage with an incoming video stream or rendering scenes according to encoded video stream scene graphs involving reformatting operations of video signals for household redistribution, storage or real-time display by decomposing into layers, e.g. base layer and one or more enhancement layers
    • 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
    • H04N21/45—Management operations performed by the client for facilitating the reception of or the interaction with the content or administrating data related to the end-user or to the client device itself, e.g. learning user preferences for recommending movies, resolving scheduling conflicts
    • H04N21/462—Content or additional data management, e.g. creating a master electronic program guide from data received from the Internet and a Head-end, controlling the complexity of a video stream by scaling the resolution or bit-rate based on the client capabilities
    • H04N21/4621—Controlling the complexity of the content stream or additional data, e.g. lowering the resolution or bit-rate of the video stream for a mobile client with a small screen
    • 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
    • H04N21/64—Addressing
    • H04N21/6405—Multicasting

Definitions

  • the present invention relates generally to data communication. More particularly, the invention relates to providing receiver-selectable video and audio quality of service over networks.
  • One of the problems associated with real time video conferencing lies in the fact that all participants may not have high-bandwidth connections to the network backbone.
  • Current optical-network transport technology provides bandwidths in excess of 10 gigabits per second (Gbps).
  • Gbps gigabits per second
  • some receivers may have access to technology such as high-speed asymmetric digital subscriber lines (ADSL) or fast Ethernet connections that provide bandwidths in excess of 100 megabits per second (Mbps)
  • other receivers may have access to technology such as token ring local area networks (LANs), thin Ethernet connections, or cable modem technology, which provide bandwidths in the range of 10 Mbps to 20 Mbps.
  • Still other receivers may have access to the network backbones through Tl lines, which provide a bandwidth of 1.544 Mbps, or integrated-services digital-network (ISDN) lines, which provide a bandwidth of 128 kilobits per second (Kbps).
  • ISDN integrated-services digital-network
  • a video signal is essentially a continuous stream of still picture images, called frames.
  • Each picture image comprises a set of pixels.
  • Each pixel is defined by a binary number. For example, 24-bit per pixel (bpp) pixels use 8 bits for each of the colors red, green, and blue.
  • the transmission of a 640x480 pixel video window at 30 frames per second requires a data rate of 27.6 Mbps, i.e., an ADSL line or a fast Ethernet connection.
  • substantial data rate savings can be accomplished by compression.
  • the data rate for large- window, full-motion video exceeds the bandwidth available to many receivers.
  • certain motion compression and decompression standards such as Moving Pictures Experts Group (MPEG), require substantial computer processing, which can make real-time viewing difficult.
  • MPEG Moving Pictures Experts Group
  • One strategy is to transmit fewer pixels by reducing the size of the window in which the video image is displayed.
  • the data rate required to transmit an image is proportional to the area of the image.
  • the window size may be reduced until the data rate becomes manageable.
  • the window may become unacceptably small.
  • Another strategy is to reduce the frame rate.
  • the data rate is also proportional to frame rate.
  • a frame rate of 30 frames per second is considered normal and can reproduce most motion effects satisfactorily.
  • the frame rate can, in certain instances, be reduced to 15 frames per second, which results in a fifty-percent reduction in data rate.
  • the transmitter uses a least common denominator solution. If any user has a lower bandwidth channel than another, then all users of the system must receive data according to the lowest bandwidth available to any one receiver. Receivers with higher bandwidth connections must receive data that is less than optimum in terms of frame rate, image size, or image quality.
  • the present invention provides a method and system for transmitting data to a number of receivers at the optimum data rate for the bandwidth of each particular receiver by allowing the receiver to select the data rate and quality.
  • data is decomposed into one or more frames, and each one of the frames may also be decomposed into bands.
  • Each one of the bands provides data in addition to the data provided by the preceding band.
  • One or more channels are established, and the frames and/or bands are transmitted on the channels.
  • Each frame and/or band may be transmitted on a different channel.
  • the frames and bands may be grouped into sets, and each set may be transmitted on a different channel.
  • the frames and bands may also be packaged into multicast datagrams.
  • the multicast datagrams are assigned multicast addresses and may be transmitted to the multicast addresses on different channels.
  • One or more of the channels are received, and the data is composed from the frames, bands, sets, or multicast datagrams provided on the received channels.
  • the system embodying the invention includes a sending terminal having a data decomposer to divide a data stream into fixed blocks of data, a compressor to compress the fixed blocks of data, and a channel generator to create one or more channels.
  • the sending terminal may transmit the fixed blocks of data at different rates and/or on different channels.
  • the sending terminal may also divide the data stream into bands, including a base band and subsequent bands. Each one of the subsequent bands provides data in addition to the base band and the data provided by the preceding band.
  • the system includes a communication link coupled to the sending terminal.
  • the communication link has a particular bandwidth.
  • the system includes one or more receiving terminals coupled to the sending terminal via the communication link. Each receiving terminal receives the fixed blocks of data and/or the bands over one or more of the channels depending on the bandwidth Of the communication link.
  • the receiving terminal composes the data from the fixed blocks of data, bands, or multicast datagrams received on the channels.
  • FIGS. 1A and IB illustrate a system embodying one form of the invention.
  • FIG. 2 illustrates a channel allocation scheme according to one form of the invention.
  • FIG. 3 illustrates an alternative channel allocation scheme according to one form of the invention.
  • FIG. 4 illustrates the operation of the system of FIGS. 1A and IB according to the alternative channel allocation scheme of FIG. 3.
  • FIG. 1A illustrates a system 11 embodying one form of the invention.
  • the system 11 includes at least one sending terminal 13 and one or more receiving terminals 15 coupled to a network 17.
  • FIG. IB further illustrates the sending terminal 13, which includes a data decomposer 14, a compressor 16, and a channel generator 18.
  • the data decompressor 14 of the sending terminal 13 processes a video data stream by decomposing the stream into frames.
  • the compressor 16 then performs progressive image compression on one or more of the frames.
  • the compressor 16 uses the Joint Photographic Experts Group (JPEG) technique or a wavelet compression technique in which the image is divided into a series of scans or bands.
  • the first or base band shows the image at a relatively-low quality setting.
  • JPEG Joint Photographic Experts Group
  • the sending terminal 13 transmits the bands individually or in groups at various frame rates on various channels.
  • the sending terminal 13 may be a desktop or laptop computer, a personal or palm computing device, a phone, a gaming device, an Internet appliances, or any other device capable of communicating over any type of network.
  • the sending terminal 13 is interfaced to the network 17 through suitable network interface hardware.
  • suitable network interface hardware such as an Ethernet card, is provided.
  • ISP Internet service provider
  • a dial-up connection appropriate network interface hardware, such as a modem, is provided.
  • the system 11 includes one or more receiving terminals
  • Each receiving terminal 15 may have a different bandwidth connection to the network 17.
  • a receiving terminal 15a may have a 100 Mbps fast Ethernet connection
  • a receiving terminal 15c may have a 10 Mbps cable modem connection
  • a receiving terminal 15n may have a 1.544 Mbps Tl connection.
  • the receiving terminals 15 may be desktop or laptop computers, personal or palm computing devices, phones, gaming devices, Internet appliances, or any other devices capable of communicating over any type of network.
  • the receiving terminals 15 are interfaced to the network 17 through suitable network interface hardware.
  • suitable network interface hardware In the case of a computer directly connected to the network 17, appropriate network interface hardware, such as an Ethernet card, is provided.
  • ISP Internet service provider
  • a dial-up connection appropriate network interface hardware, such as a modem, is provided.
  • the network 17 may be connected to the sending terminal 13 and the receiving terminals 15 through local area networks (LANs), wide area networks (WANs), public switched telephone networks (PSTNs), or any other type of network connections.
  • the network 17 may also include connection-based networks, such as those using asynchronous-transfer mode (ATM) technology.
  • ATM asynchronous-transfer mode
  • the network 17 itself may be built according to any networking technology or topology or combinations of technologies and topologies.
  • the network 17 may include packet- switched networks, such as the Internet, or circuit-switched networks, such as an asynchronous transfer mode (ATM) network.
  • ATM asynchronous transfer mode
  • the sending terminal 13 If the network 17 is a packet-switched network, such as a network using transfer control protocol/Internet protocol (TCP/IP), the sending terminal 13 generates one or more channels by creating multicast datagrams each addressed to a multicast address.
  • the term "user” refers to one who sends video data via the sending terminal 13 or receives video data via one or more of the receiving terminals.
  • a user of a receiving terminal 15 subscribes to a channel by becoming a member of the multicast group associated with the multicast address.
  • a user of a receiving terminal 15 is free to join or leave a multicast group at any time.
  • Routers (not shown) within the network 17 employ a group membership protocol to detect the presence of group members on the sub-networks that are directly attached to each router.
  • the receiving terminal 15 When a user of a receiving terminal 15 subscribes to a channel, the receiving terminal 15 transmits a group membership protocol message for the group the user wishes to join. The receiving terminal 15 also sets its Internet protocol processes and network interface card to receive packets addressed to the multicast addresses of the group.
  • the sending terminal 13 If the network 17 is a circuit-switched network, the sending terminal 13 generates one or more channels on one or more virtual circuits.
  • the receiving terminals 15 subscribe to the channels that are appropriate to their bandwidth connection on the virtual circuits.
  • FIG. 2 illustrates one preferred channel allocation scheme.
  • the sending terminal 13 transmits the data to each one of the receiving terminals 15 in three bands and at one of three frame rates (e.g., a high frame rate of thirty frames per second, a medium frame rate of fifteen frames per second, and a low frame rate often frames per second).
  • the data decomposer 14 within the sending terminal 13 decomposes the video data stream to generate thirty frames per second.
  • the sending terminal 13 transmits each one of the frames to the receiving terminal 15 for the thirty-frames-per-second frame rate.
  • the sending terminal 13 transmits every other frame to the receiving terminal 15 for the fifteen-frames-per-second frame rate.
  • the sending terminal 13 transmits every third frame to the receiving terminal 15 for the ten-frames-per-second frame rate.
  • the data decomposer 14 of the sending terminal 13 may also decompose each frame into bands, including a base band and subsequent bands.
  • the first subsequent band adds data to the base band.
  • Each of the other subsequent bands add data to the sum of the base band and each of the preceding bands.
  • the data decomposer 14 generates three bands. However, the data decomposer 14 may generate more or less than three bands.
  • the sending terminal 13 transmits Band 1 frames at the low frame rate on Channel A.
  • the sending terminal 13 provides video data having relatively low image and motion quality to the receiving terminals 15.
  • the sending terminal 13 transmits the sum of Bands 1, 2, and 3 at the high frame rate to provide video data with the highest image and motion quality to the receiving terminals 15.
  • Channel I provides substantially better image and motion quality than Charmer A
  • the receiving terminal 15 must have approximately nine-times as much bandwidth as required to receive Channel A.
  • the user of the receiving terminals 15 may trade image quality against motion quality. For example, by subscribing to Channel C, the receiving terminal 15 receives a low quality image with high quality motion, which is suitable when the motion is more important to the user than the quality of the image. Conversely, the user of the receiving terminal 15 may subscribe to Channel G when image quality is more important to the user than motion quality. For example, the user of the receiving terminal 15 may subscribe to Channel C if the video content is the head of a person or persons who are talking, i.e., "talking heads.” Alternatively, the user of the receiving terminal 15 might subscribe to Channel G if the video content is a map, chart, or document with little or no motion. Preferably, the receiving terminal 15 can change channels in real-time simply by leaving and joining appropriate multicast groups in order to receive the quality image and motion that best suits the user's current needs.
  • FIG. 3 illustrates an alternative channel allocation scheme.
  • the sending terminal 13 transmits data to the receiving terminals 15 in three bands and at three frame rates.
  • the sending terminal 13 transmits each of the three bands separately.
  • the receiving terminal 15 must subscribe to multiple channels. For example, in order to receive the highest quality image at the highest frame rate, the receiving terminal 15 must subscribe to Channels 7, 8, and 9.
  • the sending terminal 13 processes the frames as images, without compressing the motion from frame to frame.
  • the method of the present invention may be applied to systems in which motion compression is used.
  • Motion compression relies on the redundancy from frame-to-frame to reduce the data required to be transmitted.
  • the sending terminal 13 divides the video data stream into "key" frames providing full images and
  • difference frames providing information regarding the change from one frame to the next.
  • the receiving terminal 15 uses the difference frames to construct images between the key frames.
  • FIG. 4 illustrates a preferred embodiment of the operation of the system 11 of FIGS. 1A and IB.
  • an original video stream 21 is input to the compressor 16, which preferably includes a video compressor 23, within the sending terminal 13.
  • the video compressor 23 may be a software or hardware- based data compressor suitable for compressing video data.
  • the video compressor 23 decomposes the frames of the original video stream into Bands 1, 2, and 3.
  • the Bands 1, 2, and 3 are allocated by the sending terminal 13 to Channels 1 through 9 according to the channel allocation scheme of FIG. 3.
  • the Bands 1, 2, and 3 may be allocated to Channels A through I according to the channel allocation scheme of FIG. 2, or according to any other suitable channel allocation scheme.
  • each of the receiving terminals 15 includes a video decompressor
  • the video decompressors 25 may be software or hardware-based data decompressors suitable for decompressing video data.
  • the user of each of the receiving terminals 15 subscribes to one or more channels appropriate to the bandwidth of the communication link 20 to the network 17.
  • the receiving terminal 15a is associated with a video decompressor 25a and is connected to the network 17 by a low-bandwidth connection 27a. If the user of the receiving terminal 15a associated with the video compressor 25a requests a low-resolution, high-frame-rate video stream, the receiving terminal 15a subscribes to Channel 7.
  • the receiving terminal 15d subscribes to Channels 1, 2, and 3.
  • the sending terminal 13 or the receiving terminal 15 may automatically adjust which channels the receiving terminal 15 is subscribed to according to the type of video data stream.

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Databases & Information Systems (AREA)
  • Two-Way Televisions, Distribution Of Moving Picture Or The Like (AREA)
  • Data Exchanges In Wide-Area Networks (AREA)

Abstract

L"invention concerne un procédé et un système de transmission de données (21) à qualité d"image et de mouvement selectionnable par le destinataire. Les données sont décomposées en trames (figure 2), lesquelles peuvent être décomposées en bandes, chacune des bandes ajoutant des données à la bande précédente. Les trames et/ou bandes sont transmises individuellement ou en groupes à différentes vitesses sur différents canaux (figure 4). Chaque destinataire peut s"abonner aux canaux qui assurent le niveau désiré de qualité d"image et de mouvement pour la bande passante disponible pour chaque destinataire.
PCT/US2001/031861 2000-10-12 2001-10-12 Procede et systeme de transmission de qualite de service selectionnable par le destinataire sur des reseaux WO2002031670A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US23974500P 2000-10-12 2000-10-12
US60/239,745 2000-10-12

Publications (2)

Publication Number Publication Date
WO2002031670A1 true WO2002031670A1 (fr) 2002-04-18
WO2002031670A8 WO2002031670A8 (fr) 2002-06-20

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002032161A3 (fr) * 2000-10-13 2003-10-23 Genista Corp Systeme, procede et appareil relatifs a des caracteristiques de qualite pour des terminaux mobiles et internet
WO2007009996A1 (fr) * 2005-07-19 2007-01-25 France Telecom Procedes de filtrage, de transmission et de reception de flux video scalables, programmes, serveur, noeud intermediaire et terminal correspondants
WO2007101523A1 (fr) * 2006-03-07 2007-09-13 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Procede pour l'exploitation d'un reseau de transmission de donnees

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5282207A (en) * 1991-03-28 1994-01-25 Sprint International Communications Corp. Frame compression in integrated services networks
US5604824A (en) * 1994-09-22 1997-02-18 Houston Advanced Research Center Method and apparatus for compression and decompression of documents and the like using splines and spline-wavelets
US6091777A (en) * 1997-09-18 2000-07-18 Cubic Video Technologies, Inc. Continuously adaptive digital video compression system and method for a web streamer

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5282207A (en) * 1991-03-28 1994-01-25 Sprint International Communications Corp. Frame compression in integrated services networks
US5604824A (en) * 1994-09-22 1997-02-18 Houston Advanced Research Center Method and apparatus for compression and decompression of documents and the like using splines and spline-wavelets
US6091777A (en) * 1997-09-18 2000-07-18 Cubic Video Technologies, Inc. Continuously adaptive digital video compression system and method for a web streamer

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002032161A3 (fr) * 2000-10-13 2003-10-23 Genista Corp Systeme, procede et appareil relatifs a des caracteristiques de qualite pour des terminaux mobiles et internet
WO2007009996A1 (fr) * 2005-07-19 2007-01-25 France Telecom Procedes de filtrage, de transmission et de reception de flux video scalables, programmes, serveur, noeud intermediaire et terminal correspondants
FR2889017A1 (fr) * 2005-07-19 2007-01-26 France Telecom Procedes de filtrage, de transmission et de reception de flux video scalables, signal, programmes, serveur, noeud intermediaire et terminal correspondants
US8743950B2 (en) 2005-07-19 2014-06-03 France Telecom Method for filtering, transmitting and receiving scalable video streams, and corresponding programs, server, intermediate node and terminal
WO2007101523A1 (fr) * 2006-03-07 2007-09-13 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Procede pour l'exploitation d'un reseau de transmission de donnees

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