1111111111111111111111111111
`111111111111111111111111111111t11111111
`US006345389B1
`US 6,345,389 B1
`(10) Patent No.:
`US 6,345,389 B1
`(to) Patent No.:
`*Feb. 5, 2002
`(45) Date of Patent:
`(45) Date of Patent:
`*Feb. 5, 2002
`
`9!
`
`FOREIGN PATENT DOCUMENTS
`FOREIGN PATENT DOCUMENTS
`
`EP
`EP
`EP
`EP
`EP
`EP
`
`0 633 661
`() 633 661
`0 689 155
`() 689 155
`0 838 945
`() 838 945
`
`1/1995
`1/1995
`7/1996
`7/1996
`4/1998
`4/1998
`
`OTHER PUBLICATIONS
`OTHER PUBLICATIONS
`
`“Speech Recognition Methods for Controlling Cable Tele
`"Speech Recognition Methods for Controlling Cable Tele-
`vision,” IBM Technical Disclosure Bulletin, vol. 38, No. 8,
`vision," IBM Technical Disclosure Bulletin, vol. 38, No. 8,
`Aug. 1995, pp. 285–287.
`Aug. 1995, pp. 285-287.
`International Search Report, Application No. PCT/US99/
`International Search Report, Application No. PCT/US99/
`24710, mailed Feb. 15, 2000.
`24710, mailed Feb. 15, 2000.
`* cited by examiner
`* cited by examiner
`
`(12) United States Patent
`(12) United States Patent
`Dureau
`Dureau
`
`(54)
`(54)
`
`INTERACTIVE TELEVISION SYSTEM AND
`INTERACTIVE TELEVISION SYSTEM AND
`METHOD FOR CONVERTING
`METHOD FOR CONVERTING
`NON-TEXTUAL INFORMATION TO
`NON-TEXTUAL INFORMATION TO
`TEXTUAL INFORMATION BY A REMOTE
`TEXTUAL INFORMATION BY A REMOTE
`SERVER
`SERVER
`
`Inventor: Vincent Dureau, Palo Alto, CA (US)
`(75)
`Inventor: Vincent Dureau, Palo Alto, CA (US)
`(75)
`Assignee: OpenTV, Inc., Mountainview, CA (US)
`(73)
`(73) Assignee: OpenTV, Inc., Mountainview, CA (US)
`Notice:
`This patent issued on a continued pros
`(*)
`( * ) Notice:
`This patent issued on a continued pros-
`ecution application filed under 37 CFR
`ecution application filed under 37 CFR
`1.53(d), and is subject to the twenty year
`1.53(d), and is subject to the twenty year
`patent term provisions of 35 U.S.C.
`patent term provisions of 35 U.S.C.
`154(a)(2).
`154(a)(2).
`Subject to any disclaimer, the term of this
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`U.S.C. 154(b) by 0 days.
`
`Primary Examiner—Chris Grant
`Primary Examiner—Chris Grant
`(74) Attorney, Agent, or Firm—Conley, Rose & Tayon, PC
`(74) Attorney, Agent, or Firm—Conley, Rose & Tayon, PC
`(57)
`ABSTRACT
`ABSTRACT
`(57)
`A system and method for providing user input to an appli
`A system and method for providing user input to an appli-
`Appl. No.: 09/176,611
`(21)
`(21) Appl. No.: 09/176,611
`cation executing on an interactive television system wherein
`cation executing on an interactive television system wherein
`(22)
`Filed:
`Oct. 21, 1998
`a user provides non-textual information to the interactive
`Oct. 21, 1998
`(22) Filed:
`a user provides non-textual information to the interactive
`television system and this information is converted by a
`television system and this information is converted by a
`Int. Cl." … H04N 7/173
`(51)
`HO4N 7/173
`
`Int. C1.7
`(51)
`server to textual information which is provided to the
`server to textual information which is provided to the
`(52)
`U.S. Cl. ........................................ 725/116; 72.5/133
`(52) U.S. Cl.
` 725/116; 725/133
`application. In one embodiment, a digitizer pad coupled to
`application. In one embodiment, a digitizer pad coupled to
`(58)
`Field of Search .............................. 348/1, 2, 6, 10,
`(58) Field of Search
` 348/1, 2, 6, 10,
`a set-top box is used to digitize the user’s handwriting. The
`a set-top box is used to digitize the user's handwriting. The
`348/12, 13, 14; 455/2, 3.1, 6.1, 5.1, 6.2,
`348/12, 13, 14; 455/2, 3.1, 6.1, 5.1, 6.2,
`digitized information is conveyed to a remote server which
`digitized information is conveyed to a remote server which
`6.3; 345/327; 382/187, 189; 704/235; 725/131,
`6.3; 345/327; 382/187, 189; 704/235; 725/131,
`converts the digitized handwriting data into textual infor
`converts the digitized handwriting data into textual infor-
`132, 116, 139, 140, 151, 152, 133
`132, 116, 139, 140, 151, 152, 133
`mation. The textual information is conveyed to the set-top
`mation. The textual information is conveyed to the set-top
`box, where it is input to an application executing on the
`box, where it is input to an application executing on the
`set-top box. In another embodiment, a microphone is
`set-top box. In another embodiment, a microphone is
`coupled to a set-top box. The microphone allows the user to
`coupled to a set-top box. The microphone allows the user to
`input voice information which is digitized and conveyed to
`input voice information which is digitized and conveyed to
`the server for conversion into textual information. The
`the server for conversion into textual information. The
`textual information is conveyed back to the set-top box and
`textual information is conveyed back to the set-top box and
`is input to an application executing on the set-top box.
`is input to an application executing on the set-top box.
`
`(56)
`(56)
`
`References Cited
`References Cited
`
`U.S. PATENT DOCUMENTS
`U.S. PATENT DOCUMENTS
`
`707/541
`
`5,528,743 A * 6/1996 Tou et al.
`5,528,743 A * 6/1996 Tou et al. ................... 707/541
`5,546,538 A * 8/1996 Cobbley et al. ....... 395/200.01
`5,546,538 A * 8/1996 Cobbley et al.
` 395/200.01
`5,812,931 A * 9/1998 Yuen
`
`455/5.1
`5,812,931 A * 9/1998 Yuen .......................... 455/5.1
`5,831,664 A * 11/1998 Wharton et al.
`
`348/13
`5,831,664 A * 11/1998 Wharton et al. .............. 348/13
`5,861,881 A * 1/1999 Freeman et al.
`
`345/302
`5,861,881 A * 1/1999 Freeman et al. .....
`... 345/302
`5,875,448 A * 2/1999 Boys et al.
`
`707/531
`5,875,448 A * 2/1999 Boys et al. ..........
`... 707/531
`
`22 Claims, 3 Drawing Sheets
`22 Claims, 3 Drawing Sheets
`
`SET-TOP BOX
`SET-TOP BOX
`22
`22
`
`INPUT DEVICE
`INPUT DEVICE
`24
`24
`
`TV PROGRAM
`TV PROGRAM
`SOURCE
`SOURCE
`11
`11
`L
`
`COMP/PKT.
`COMP/PKT.
`14
`14
`
`
`
`APPLICATION
`APPLICATION
`|
`SOURCE |-- coºki
`COMP/PKT.
`SOURCE
`15
`12
`15
`12
`
`
`
`
`
`SERVER
`SERVER
`13
`13
`
`
`
`
`
`COMP/PKT.
`COMP/PKT.
`16
`16
`
`28
`
`
`
`
`
`7 19
`19
`
`21
`
`M
`U
`U
`X
`X
`17
`17
`
`D
`E
`M
`U
`X
`
`18
`
`10
`10
`
`20
`
`Comcast - Exhibit 1009, page 1
`
`

`

`Waled *S11
`U.S. Patent
`
`Feb. 5, 2002
`
`Sheet 1 of 3
`£ JO 1 13311S
`
`345,389 B1
`iff 68C`S17C`9 Sfl
`US 6
`
`4
`
`INPUT DEVICE
`24
`
`SET-TOP BOX
`22
`i
`TV
`23
`
`XO8 dO LT LES
`Zz
`
`FIG. 1
`
`20
`
`§
`
`CO CN :
`
`M
`U
`X
`
`17
`
`D
`E
`M
`U
`X
`
`18
`
`TV PROGRAM
`SOURCE
`11
`
`APPLICATION
`SOURCE
`12
`
`COMP/PKT.
`14
`
`COMP/PKT.
`15
`
`SERVER
`13
`
`H COMP/PKT.
`16
`
`10
`
`Comcast - Exhibit 1009, page 2
`
`

`

`U.S. Patent
`U.S. Patent
`
`Feb. 5, 2002
`Feb. 5, 2002
`
`Sheet 2 of 3
`Sheet 2 of 3
`
`US 6,345,389 B1
`US 6,345,389 B1
`
`BROADCAST
`BROADCAST
`SIGNAL
`
`SIGNAL
`
`22
`22
`
`
`
`L
`
`TUNER
`TUNER
`31
`
`# It
`
`PROCESS
`PROCESS
`32
`
`DECOMP,
`DECOMP.
`33
`
`DISPLAY
`DISPLAY
`-- P- TO TV
`34
`
`?ºlº {-TOTV
`
`IT
`
`CPU
`35
`
`ROM
`36
`
`RAM
`37
`
`MODEM
`38
`
`USER INPUT
`USER INPUT
`
`GRAPHICS | TO PHONE
`GRAPHICS
`TO PHONE
`LINE
`TABLET
`TABLET
`LINE
`39
`39
`
`USER INPUT
`USER INPUT
`
`FIG. 2
`FIG. 2
`
`
`
`DISPLAY 51
`A
`DIGITIZER 52
`
`PROC.
`53
`
`FIG. 3
`
`Comcast - Exhibit 1009, page 3
`
`

`

`U.S. Patent
`U.S. Patent
`
`Feb. 5, 2002
`Feb. 5, 2002
`
`Sheet 3 of 3
`Sheet 3 of 3
`
`US 6,345,389 B1
`US 6,345,389 B1
`
`START
`START
`APPLICATION
`APPLICATION
`61
`61
`i
`PROMPT USER
`PROMPT USER
`62
`62
`i
`
`INPUT
`INPUT
`HANDWRITING
`HANDWRITING
`63
`63
`+
`TRANSFER
`TRANSFER
`HANDWRITING
`HANDWRITING
`DATA
`DATA
`64
`64
`+
`RECOGNIZE
`RECOGNIZE
`HANDWRITING
`HANDWRITING
`65
`65
`i
`
`TRANSFER
`TRANSFER
`TEXTUAL DATA
`TEXTUAL DATA
`66
`66
`
`i
`
`UTILIZE
`UTILIZE
`TEXTUAL DATA
`TEXTUAL DATA
`67
`67
`
`FIG. 4
`FIG. 4
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`SEGMENT
`SEGMENT
`|MAGE
`IMAGE
`71
`71
`i
`SELECT
`SELECT
`CHARACTER
`CHARACTER
`CANDIDATES
`CANDIDATES
`72
`72
`i
`CLASSIFY
`CLASSIFY
`CANDIDATES
`CANDIDATES
`73
`73
`
`
`
`
`
`ORGANIZE
`ORGANIZE
`CANDIDATES
`CANDIDATES
`74
`74
`+
`DICTIONARY
`DICTIONARY
`LOOKUP
`LOOKUP
`75
`75
`i
`ACCEPTABILITY
`ACCEPTABILITY
`CHECK
`CHECK
`76
`76
`i
`USER CHECK
`USER CHECK
`77
`77
`
`FIG. 5
`FIG. 5
`
`Comcast - Exhibit 1009, page 4
`
`

`

`US 6,345,389 B1
`
`1
`INTERACTIVE TELEVISION SYSTEM AND
`METHOD FOR CONVERTING NON-
`TEXTUAL INFORMATION TO TEXTUAL
`INFORMATION BY A REMOTE SERVER
`
`BACKGROUND OF THE INVENTION
`
`5
`
`25
`
`1. Field of the Invention
`The invention relates generally to interactive television
`systems and more particularly to means and methods for
`using a server to convert user-provided information into a 10
`data format which can be used by an interactive television
`application.
`2. Description of the Relevant Art
`Interactive television systems can be used to provide a 15
`variety of services to users. These systems are capable of
`displaying text and graphic images to facilitate viewer
`interaction as well as the audio and video streams associated
`with ordinary television programs. Interactive television
`systems enable viewer interaction and thereby allow the 20
`systems to be used for marketing and educational purposes
`in addition to extending the entertainment capabilities of an
`ordinary television. Viewers can order advertised products
`or services, request information regarding particular
`programs, or send electronic messages (e-mail).
`In a typical interactive television system, a broadcast
`service provider generates an interactive television signal for
`transmission to a viewer's television. The interactive tele-
`vision signal includes an audio-video portion consisting of a
`television program, as well as an interactive portion con-
`30
`sisting of application code or control information. The
`broadcast service provider combines the audio-video and
`interactive portions into a single signal for transmission to a
`receiver connected to the user's television. The signal is
`typically compressed prior to transmission and transmitted 35
`through broadcast channels such as cable television (CATV)
`lines or direct satellite transmission systems.
`The interactive functionality of the interactive television
`system is controlled by a set-top box connected to the
`television. The set-top box receives the signal transmitted by 40
`the broadcast service provider, separates the interactive
`portion from the audio-video portion and decompresses the
`respective portions of the signal. If the interactive portion of
`the signal comprises an interactive application, the applica-
`tion may be executed while the audio-video information (the 45
`normal television signal) is conveyed to the television. The
`set-top box may combine the audio-video information with
`interactive graphics or audio generated by the interactive
`application prior to conveying the information to the tele-
`vision. The interactive graphics and audio may present 50
`additional information to the viewer or may prompt the
`viewer for input and may be designed to function in response
`to signals in the broadcast or actions taken by the viewer. An
`interactive television system may also run applications that
`present the user only with the audio and graphics relating to 55
`the interactive application. In other words, this information
`may be displayed in place of the normal television signal,
`rather than adding to the signal.
`There are various examples of interactive applications
`which require viewer input. One example is a televised 60
`buying service in which a series of products are displayed
`via a television program and the viewer utilizes the inter-
`active functions of the television system to purchase the
`displayed products. The viewer must identify the product he
`or she wishes to purchase and may also need to provide size, 65
`color, and other information descriptive of the product. This
`information may be provided by selecting the appropriate
`
`2
`choice from a menu. The application may, however, also
`require the user's name or shipping information which
`cannot simply be selected from a menu. Another example of
`an application which requires textual information is a mes-
`saging application for which the viewer must provide the
`message, as well as information identifying the addressee of
`the message. Some means is therefore necessary to enter this
`textual information.
`One option for entering text would be to use a keyboard.
`This might not be the best solution, however, because some
`users may not feel comfortable using a keyboard. One of the
`attractions of interactive television systems is the ease with
`which they may be used. Interactive television applications
`are designed to provide simplified user interfaces and many
`require no more input than can be provided using a basic
`remote control. The requirement of entering textual infor-
`mation via a keyboard may make the interactive television
`system less attractive to users because of the additional
`hardware which is required for the system, the perceived
`complexity of the system or the difficulty which may be
`experienced by some users in typing the necessary informa-
`tion. Further, in some languages (e.g., Chinese,) the com-
`plexity of the written language makes text entry via a
`keyboard difficult even for experienced users.
`Other options for providing textual information to an
`application may involve means for converting non-textual
`information into a textual form. For example, using voice
`recognition technology, a user's voice can be sampled and
`compared to previously sampled speech patterns to deter-
`mine the words spoken by the user. The words can then be
`output by the speech recognition system as text. Handwrit-
`ing recognition systems could also be used to generate
`textual information for the application. These systems per-
`form the same process on images of the user's handwriting
`(entered via a graphics tablet or similar input device) to
`determine the text written by the user. While these technolo-
`gies have evolved to the point that they can reliably generate
`accurate textual information from the user's voice or
`handwriting, they require a great deal of computer resources.
`The applications may be very large and they need large
`amounts of processing time to perform the required pattern
`matching. These technologies therefore cannot be imple-
`mented in current set-top boxes, which have very limited
`storage and processing capacity.
`
`SUMMARY OF THE INVENTION
`
`One or more of the problems outlined above may be
`solved by the various embodiments of the invention. The
`invention comprises a system and method for enabling a
`user to provide non-textual information which is converted
`by the system to a textual form in which it can be used by
`the interactive application. The non-textual information is
`entered by the user at the set-top box of a receiving station
`and this information is transmitted to a server which may be
`located at a broadcast station. The server converts the
`information into textual data so that it can be used by the
`system. In one embodiment, the server transmits the textual
`data back to the receiving station, where it can be used by
`an application executing in the set-top box. In other
`embodiments, the textual data can be used at the server or
`transmitted to a part of the system other than the set-top box.
`One embodiment comprises an interactive television sys-
`tem comprising a broadcast station and a receiving station.
`The broadcast station transmits an interactive television
`application to the receiving station, which then executes the
`application. The application requires textual data from the
`
`Comcast - Exhibit 1009, page 5
`
`

`

`US 6,345,389 B1
`
`3
`user. The receiving station includes a set-top box which
`executes the application and a graphics tablet which is
`coupled to the set-top box for entering information. The user
`provides the information by writing on the graphics tablet,
`which generates an image file. The image file is transmitted
`from the set-top box to the broadcast station. The broadcast
`station includes a server which uses handwriting recognition
`software to convert the image file into character or textual
`data. The textual data is transmitted back to the application
`at the set-top box, which uses the data as if it had been typed 10
`in directly by the user.
`Because the handwriting recognition software resides on
`the server computer instead of the set-top box, more
`resources are available for execution of the software. The
`server typically has more available memory and more pro-
`cessing power than the set-top box and consequently pro-
`vides much faster recognition of handwriting images. The
`greater available resources enable the software to provide
`for recognition of additional, complex languages (e.g.,
`Chinese) and extended character sets (e.g., unicode). Since
`the recognition software is maintained on the server, the
`software can be quickly and easily updated with the latest
`handwriting recognition technology, and it does not have to
`be distributed to the individual subscribers' set-top boxes.
`In one embodiment, the textual data need not be sent back
`to the set-top box, but may instead be used at the server or
`another location remote from the set-top box. For example,
`a user may place an order for a product by entering oral or
`handwritten information and the order may be confirmed
`later by e-mail or other means. In another embodiment, the
`server could consist of a human operator who receives the
`audio or image data and manually transcribes it into textual
`information. The audio or image data may alternately be
`converted into textual information by automated means
`operating under human supervision.
`In an alternate embodiment, the interactive television
`system includes a microphone rather than a graphics tablet
`for entry of information to the system. The microphone is
`used to provide voice data, which is recorded and transmit-
`ted to a server equipped with a voice recognition application.
`The voice recognition application converts the voice data
`into textual data, which is then transmitted back to the
`application executing on the set-top box.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`Other objects and advantages of the invention will
`become apparent upon reading the following detailed
`description and upon reference to the accompanying draw-
`ings in which:
`FIG. 1 is a block diagram illustrating one embodiment of
`a system for distribution of interactive television applica-
`tions and television programs from their sources to a series
`of viewers.
`FIG. 2 is a block diagram of a set-top box in one
`embodiment of the invention.
`FIG. 3 is a block diagram illustrating the components of
`a graphics tablet in one embodiment of the invention.
`FIG. 4 is a flow diagram illustrating the flow of
`handwritten/textual information in one embodiment of the
`invention.
`FIG. 5 is a flow diagram illustrating the manner in which
`the server's handwriting recognition application processes
`the image data to produce textual data in one embodiment of
`the invention.
`While the invention is susceptible to various modifica-
`tions and alternative forms, specific embodiments thereof
`
`4
`are shown by way of example in the drawings and will
`herein be described in detail. It should be understood,
`however, that the drawing and detailed description thereto
`are not intended to limit the invention to the particular form
`5 disclosed, but on the contrary, the intention is to cover all
`modifications, equivalents and alternatives falling within the
`spirit and scope of the present invention as defined by the
`appended claims.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`One embodiment of the inventive method is described in
`detail below. In this embodiment, an interactive television
`system transmits an audio-video-interactive signal from a
`is broadcast station to a receiving station via a broadcast
`channel. ("Broadcast" is used herein to refer to transmission
`of a single signal to all subscribing receivers.) The broadcast
`channel may comprise a direct satellite transmission channel
`or any known means for broadcasting a signal, including
`20 non-satellite, cable, telco, MMDS (microwave) and terres-
`trial transmissions. (A "direct" satellite transmission as used
`herein means a transmission received by the interactive
`television receiver directly from the satellite.). The receiving
`station in this embodiment is additionally configured to
`25 receive signals via a modem connection to the broadcast
`station.
`The audio-video-interactive signal broadcast to the
`receiving station may contain both television programming
`and interactive information such as control signals or inter-
`30 active applications. When the broadcast signal is received, it
`is separated into its components and processed (e.g.,
`decompressed) to reconstruct the respective television pro-
`gramming and interactive signals. An interactive application
`which was broadcast to the receiving station or which was
`35 resident in the receiving station is executed on the micro-
`processor of the set-top box. The application is one which
`requires textual data from the user. The user, however, is
`allowed to input the data in a non-textual form. "Non-
`textual" as used herein means a form handled by the system
`40 as something other than a series of alphanumeric characters,
`such as the ASCII character set. A graphical representation
`of handwriting, although textual in nature, is handled as an
`image or as vectorized handwriting information and not as
`the characters or words which are written. "Textual," on the
`45 other hand, means one or more characters or words. If the
`system is set up for an English-speaking user, the characters
`may be from the ASCII character set. If the system is set up
`for a non-English-speaking user, the characters will be from
`the character set of the user's language (e.g., Kanji charac-
`so ters for a Japanese user).
`The set-top box of the receiving station is configured with
`a device for non-textual data entry. In one embodiment, this
`device is a graphics tablet on which the user can inscribe
`(write) the information required by the application. The
`55 graphics tablet digitizes the user's handwriting and stores
`the digitized data as an image file. The set-top box transmits
`the file containing the digitized data to the broadcast station
`for conversion into a textual form. (The image data need not
`all be contained in a single file, and may be transmitted to
`60 the server in segments to spread out the processing load.)
`The broadcast station includes a server which is configured
`to transform image data into textual data using handwriting
`recognition algorithms. The broadcast station then transmits
`the textual data back to the receiving station. The application
`65 executing on the set-top box identifies the received textual
`data as corresponding to the image data which it earlier
`transmitted to the broadcast station. The set-top box accord-
`
`Comcast - Exhibit 1009, page 6
`
`

`

`US 6,345,389 B1
`
`5
`ingly utilizes the textual data as if it had been entered as text
`by the user of the set-top box and continues execution of the
`interactive television application.
`Referring to FIG. 1, a block diagram illustrating a system
`for distribution of interactive television applications and
`television programs from their sources to a series of viewers
`is shown. Broadcast station 10 has a television program
`source 11 and an interactive application source 12. The
`television program source may include remote broadcast
`network feeds, videotape recorders, computers, data storage
`devices, and the like. Interactive application sources 12 may
`provide interactive applications, control information or
`audio or video information which is to be included in the
`interactive television signal. Additionally, broadcast station
`10 includes a server 13, which is used to process non-textual
`data received at the broadcast station and generate textual
`data. The information generated by the television program
`source 11, interactive application source 12 and server 13 is
`typically processed by compression/packetization units
`14-16 before it is broadcast. Usually, the information is also
`compressed in order to conserve bandwidth. (It should be
`noted that while this embodiment comprises a digital broad-
`cast system, other embodiments may comprise analog
`broadcast systems in conjunction with means for transmit-
`ting digital application data. The analog broadcast systems
`may include existing television networks, and the means for
`transmitting the application data may include transmissions
`in the vertical blanking interval or parallel transmissions via
`telephone lines or out-of-band cable signals.)
`Any of a number of compression algorithms, such as one
`of the Motion Picture Expert Group (MPEG) compression
`standards, may be used if appropriate for a particular pro-
`gram or application. The information is packetized to enable
`error checking, interleaving of data and other transmission-
`related functions. Additional data may accordingly be
`appended to the application and programming data. For
`example, error check sums may be appended for error
`detection/correction and time stamps may be included for
`the purpose of synchronizing associated audio and video
`signals. The packetized information from compression/
`packetization units 14-16 is fed into multiplexing unit 17,
`which intersperses the packets prior to transmission. The
`interspersed packets are then broadcast to the receiving
`stations 20. (Although only one receiving station is shown in
`the figure, it is contemplated that the audio-video-interactive
`signal is broadcast to a group of subscribing receiving
`stations.) In the figure, the audio-video-interactive signal is
`depicted as being transmitted via satellite broadcast through
`antenna 19.
`The broadcast signal is relayed by communications sat-
`ellite 28 and received by receiving station 20. Although the
`figure illustrates a satellite transmission, it is contemplated
`that any broadcast medium (e.g., CATV or direct satellite
`transmission) may be used. Receiving station 20 is contem-
`plated to be one of a number of such stations which are
`subscribers of the broadcast service provider operating
`broadcast station 10. The broadcast signal is collected by
`receiving antenna 21 and fed to set-top box 22. Set-top box
`22 processes the packetized signal to reconstruct the televi-
`sion programs and interactive applications embodied in the
`signal. The reconstructed applications are executed in the
`set-top box, while the reconstructed television programs are
`passed to television 23, where they are displayed. (It is noted
`that television 23 can be any suitable monitor or display
`device.) The interactive applications may generate graphics
`or audio which are combined with the television program
`prior to being displayed. The interactive applications may
`also be displayed in place of the television programming.
`
`6
`In addition to the broadcast channel between the broad-
`cast station and receiving station, there may be other
`channels, such as a modem channel (which may also be
`referred to as an http channel, or hypertext transfer protocol
`5 channel.) These types of channels serve two functions in the
`system: they allow the set-top box to provide data to the
`broadcast station; and they provide an alternate path for
`from sources 11-13 to be delivered to receiving station 20.
`It should also be noted that, if receiving station 20 and server
`10 13 are connected via a transmission medium other than the
`broadcast station's broadcast channel and return path, the
`server is not constrained to be located at the broadcast
`station. It may be more convenient to locate server 13 at a
`site which is separate from broadcast station 10 in order to
`15 reduce the workload of the broadcast station, to more
`efficiently convey data between the receiving station and the
`server, or for other reasons.
`Referring to FIG. 2, a block diagram of a set-top box 22
`in one embodiment is shown. The broadcast signal is
`20 received and fed into tuner 31. Tuner 31 selects the channel
`on which the broadcast audio-video-interactive signal is
`transmitted and passes the signal to processing unit 32.
`(Tuner 31 may be replaced by other means, all collectively
`referred to herein as input ports, for receiving signals from
`25 various signal sources.) Processing unit 32 demultiplexes
`the packets from the broadcast signal if necessary and
`reconstructs the television programs and/or interactive
`applications embodied in the signal. The programs and
`applications are then decompressed by decompression unit
`30 33. The audio and video information associated with the
`television programs embodied in the signal is then conveyed
`to display unit 34, which may perform further processing
`and conversion of the information into a suitable television
`format, such as NTSC or HDTV audio/video. Applications
`35 reconstructed from the broadcast signal are routed to random
`access memory (RAM) 37 and are executed by micropro-
`cessor 35. Graphics tablet 39 provides a means for the user
`to supply handwritten information for conversion to text and
`subsequent use by the applications. (In other embodiments,
`40 graphics tablet 39 may be replaced by a microphone for
`supplying voice data or some other type of input device for
`supplying non-textual information to the system.)
`Microprocessor 35 may comprise various types of
`microprocessors, microcontrollers, digital signal processors
`45 (DSPs), or other types of software instruction processing
`devices, as are appropriate to the particular design. RAM 37
`may include memory units which are static (e.g., SRAM),
`dynamic (e.g., DRAM), volatile or non-volatile (e.g., Flash
`memory), as required to support the functions of the set-top
`50 box. When power is applied to the set-top box, micropro-
`cessor 35 executes operating system code which is stored in
`ROM 36. (In some embodiments, ROM 36 may comprise
`Flash memory or EEPROMs.) The operating system code
`executes continuously while the set-top box is powered in
`55 the same manner the operating system code of a typical
`personal computer (PC) and enables the set-top box to act on
`control information and execute interactive and other appli-
`cations. The set-top box also includes modem 38. Modem 38
`provides both a return path by which viewer data can be
`60 transmitted to the broadcast station and an alternate path by
`which the broadcast station can transmit data to the set-top
`box.
`Although the term "set-top box" is used herein, it is
`understood that this term refers to any receiver or processing
`65 unit for receiving and processing a transmitted signal and
`conveying the processed signal to a television or other
`monitor. The set-top box may be in a housing which
`
`Comcast - Exhibit 1009, page 7
`
`

`

`US 6,345,389 B1
`
`7
`physically sits on top of a television, it may be in some other
`location external to the television (e.g., on the side or back
`of the television or remotely located from the television), or
`it may be incorporated into the television itself.
`Alternatively, the functionality of the set-top box may be
`entirely removed from the television and placed in a more
`remote location, such as outside a house in which the settop
`box is located. Set-top box 22 serves to demodulate (if
`necessary) the signal received from broadcast station 10 and
`to separate the components of the signal, such as different
`television programs and interactive applications. Other
`embodiments of the set-top box may have different compo-
`nents or interconnections than those shown in FIG. 2.
`Similarly, television 23 may be a television or a video
`monitor employing any suitable television format (e.g.,
`NTSC or HDTV), or it may be replaced by other devices,
`such as a video recorder, depending on the particular
`embodiment.
`Referring to FIG. 3, a block diagram illustrating the
`components of a graphics tablet 50 is shown. The main
`components of graphics tablet 50 are display 51, digitizer 52
`and processor 53. Graphics tablet 50 can have a wide range
`of sizes, from several inches across (as used in pen com-
`puting systems) to several feet across (as used in some CAD
`systems). It is contemplated that the most convenient size for
`the graphics tablet will be the size of a small or medium
`sized notepad. The surface of graphics tablet 50 should be
`flat and smooth to facilitate use as a writing surface.
`Although graphics tablet 50 is contemplated to be connected
`to set-top box 22 by a data cable, infrared transmission or
`any other su