Controlled-access broadcast signal receiving system

Information

  • Patent Grant
  • RE38007
  • Patent Number
    RE38,007
  • Date Filed
    Thursday, August 17, 2000
    23 years ago
  • Date Issued
    Tuesday, February 25, 2003
    21 years ago
Abstract
An apparatus and method for transferring from a broadcaster to a receiver a limited reproduction right in data. A signal indicating the limited reproduction right is transmitted by the broadcaster and stored by the receiver with the data. The receiver reproduces and processes the data as a function of this signal.
Description




BACKGROUND OF THE INVENTION




This invention relates to video data communication in which a limited reproduction right in video data is transferred between a broadcaster and a receiver.




Commonly, video programming is transmitted from a broadcaster to a user via a satellite or cable communications system. In some systems, users are able to request, and broadcasters provide, select video programming through the use of individually addressable decoding receivers. The user's decoder is activated upon receipt of the user's address which is transmitted along with the requested video programming.




The drawback of such systems is that the user is often able to record the requested video programming for later reproduction. This later reproduction occurs without any royalty payment to the broadcaster or other holder of copyrights in the video programming. Further, the recorded video programming can be disseminated by the user to others for additional reproductions without corresponding royalty payments.




OBJECTS AND SUMMARY OF THE INVENTION




An object of the present invention is to provide a system for the transfer between a broadcaster and a user of a limited reproduction right in transmitted data.




Another object of the present invention is to enable a user to request from a broadcaster a particular limited reproduction right in a selected video program.




Yet another object of the present invention is to prevent the reproduction of transmitted data by a user without adequate payment for each reproduction.




In accordance with the present invention, an apparatus for receiving, recording, and reproducing data signals is provided. A receiver receives transmitted data signals along with an access-control signal, the latter serving to control subsequent processing of the received data signals. The processed data signals are recorded in a first storage medium, and the access-control signal is stored in a second storage medium. When the processed data signals subsequently are reproduced from the first storage medium the access-control signal is retrieved from the second storage medium, and is used to control the reprocessing of the reproduced data signals.




The above, and other objects, features and advantages of the present invention will become apparent from the following detailed description of illustrative embodiments when read in conjunction with the accompanying drawings in which the same components are identified by the same reference numerals.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a schematic diagram of a satellite broadcast system in which the present invention finds ready application;





FIG. 2

is a block diagram of a controlled-access broadcast digital video signal receiving system according to one embodiment of the present invention;





FIG. 3

is a block diagram of a controlled-access broadcast digital video signal receiving system according to another embodiment of the present invention;





FIG. 4

is a block diagram of a controlled-access broadcast digital video signal receiving system according to a further embodiment of the present invention;





FIG. 5

is a block diagram of a controlled-access broadcast digital video signal receiving system according to yet another embodiment of the present invention;





FIG. 6

is a flow diagram illustrating a communication and processing operation controlled by the controller of the controlled-access broadcast digital video signal receiving system of

FIG. 2

; and





FIG. 7

is another flow diagram illustrating another processing operation controlled by the controller of the controlled-access broadcast digital video signal receiving system of FIG.


2


.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS





FIG. 1

illustrates a satellite broadcast system incorporating a controlled-access broadcast signal receiving system


102


according to the present invention. As explained in the following, it is preferred that the controlled-access broadcast signal receiving system


102


be specifically adapted to receive and process digital video data. Nevertheless, it should be appreciated that this system can be modified to accommodate other digital or analog signals without departing from the scope of the invention. As it is understood that the system can easily be implemented to accommodate other types of data, the following explanation is specifically directed towards a controlled-access broadcast digital video signal receiving system


102


.




The satellite television broadcasting system comprises a broadcasting station


101


, controlled-access broadcast digital video signal receiving system


102


, an antenna


103


, a video display


105


, a communication link


106


, and a satellite


107


. Broadcasting station


101


broadcasts video signals and access-control signals to the controlled-access broadcast digital video signal receiving system


102


which processes the video signals as a function of the access-control signals.




Broadcasting station


101


transmits video and access-control signals to receiving system


102


via communication link


106


, satellite


107


, or both. Communication link


106


is a signal transmission medium that couples broadcasting station


101


and receiving system


102


. Preferably, communication link


106


comprises a conventional telephone line. Alternatively, communication link


106


includes any of a number of other transmission media, such as a land-based broadcast system, a cable television system, a fiber optic network or the like.




Satellite


107


is a satellite broadcast signal relay station that receives signals from broadcasting station


101


and relays the signals to antenna


103


. Antenna


103


receives signals from satellite


107


and supplies the signals to receiving system


102


. Alternatively, satellite


107


can be replaced by any of a number of other transmission media, such as a land-based broadcast system, a cable television system, a fiber optic network or the like.




Receiving system


102


receives video signals and access-control signals supplied by broadcasting station


101


and processes (e.g. descrambles, decodes, and records) the signals. Typically, video signals are recorded on a storage medium and subsequently reproduced for display. Alternatively, video signals are recorded on a storage medium and processed for display to a user substantially simultaneously. Access-control signals are stored in a memory or, alternatively, recorded on a storage medium which may be the same storage medium on which the video signals are recorded. In a preferred embodiment, receiving system


102


is adapted to receive a storage cassette


104


containing a tape on which video and access-control signals are recorded. Alternatively, storage cassette


104


comprises a tape for storing video signals and a separate memory, such as a memory chip included therein, for storing access-control signals. In other embodiments, receiving system


102


is adapted to receive any of a number of other storage media, such as a video disc, a magnetic media diskette, a compact disc or the like. Video display


105


, which preferably is a conventional display device, is coupled to and receives video signals from receiving system


102


for display to a user.




In a preferred recording mode of operation, broadcasting station


101


transmits video signals to satellite


107


which relays the signals to antenna


103


from which the video signals are coupled to receiving system


102


. Also, broadcasting station


101


transmits access-control signals through communication link


106


to the receiving system. Receiving system


102


processes and records the video signals as a function of the access-control signals.




In a preferred reproduction mode of operation, the receiving system retrieves the previously stored access-control signals and uses those access-control signals to control the reproduction and processing of the previously recorded video signals. The video signals are supplied to video display


105


or to another peripheral device (not shown).




An alternate satellite television broadcasting system according to the present invention comprises each of the elements described above except that only one of communication link


106


and satellite


107


is included. The alternate system is otherwise interconnected as in the above-described embodiment. Through the single transmission medium, broadcasting station


101


transmits both video signals and access-control signals to receiving system


102


.




In another variation, receiving system


102


transmits program requests, payment information, or other signals to broadcasting station


101


through one of the transmission media. Typically, communication link


106


is used for this purpose.




A first embodiment of the controlled-access broadcast digital video signal receiving system


102


according to the present invention is illustrated in

FIG. 2

as system


102


A. Receiving system


102


A, is adapted for receiving, descrambling, enciphering, recording, deciphering and decoding digital video signals; and is comprised of a tuner


20


, a descrambler


21


A, an encipherer


22


, a recording/reproducing section


23


A, a decipherer


25


, a decoder


26


, an access controller


28


A, a user interface


30


, and a modem


31


.




Tuner


20


receives input digital video signals, selects particular digital video signals, and supplies the selected signals to descrambler


21


A. Preferably, input digital video signals are satellite broadcast digital video signals acquired by satellite antenna


103


which is coupled to tuner


20


. Alternatively, input digital video signals are acquired from another transmission medium that is coupled to tuner


20


. Preferably, a user controls tuner


20


to select signals from among different input digital video signals. The selected video signals include a time reference signal and a date reference signal.




Descrambler


21


A is coupled to tuner


20


and descrambles scrambled digital video signals supplied therefrom. As is well known in the art, transmitted video signals are commonly scrambled or coded by a signal provider to prevent unauthorized reception of the video signals. Descrambler


21


A supplies an unscrambled version of the digital video signals to encipherer


22


. Further, descrambler


21


A is coupled to a clock


27


to supply the received time reference signal and the date reference signal thereto.




Encipherer


22


is coupled to descrambler


21


A, recording/reproducing section


23


A, and access controller


28


A. When enabled by the access controller, encipherer


22


encrypts, according to an encryption key, descrambled video signals supplied by descrambler


21


A to produce encrypted video signals. The encrypted video signals are supplied to recording/reproducing section


23


A for recording. However, the encrypted video signals cannot be displayed by ordinary means. It is contemplated that the encryption key is prestored in encipherer


22


, or is supplied by access controller


28


A, or is included in the video signals or in the access-control signals supplied by broadcasting station


101


. When disabled by access controller


28


A, encipherer


22


passes descrambled video signals from descrambler


21


A directly to section


23


A without encryption.




Recording/reproducing section


23


A, through a record/playback head


24


, or the like, records on storage medium


40


video signals supplied by encipherer


22


. Section


23


A, through head


24


, also reads previously recorded video signals from storage medium


40


and supplies the reproduced video signals to decipherer


25


. Preferably, section


23


A is a digital video tape recording/reproducing device (VTR) and storage medium


40


is a video tape. However, other types of storage media are contemplated, such as optical, magnetic or magneto-optic disc, solid-state memory, or the like.




Decipherer


25


is coupled to decoder


26


and, when enabled by access controller


28


A, is adapted to decrypt, according to an encryption key, encrypted signals supplied by recording/reproducing section


23


A. It is contemplated that the encryption key is prestored in decipherer


25


, or is supplied thereto by access controller


28


A, or is included in the video signals or the access-control signals supplied by broadcasting station


101


, or is stored in storage medium


40


, or is stored in access condition memory


29


. When disabled, decipherer


25


passes video signals from recording/reproducing section


23


A directly to decoder


26


without decryption.




As is well known in the art, video signals are commonly compressed or otherwise coded to facilitate their transmission through a transmission medium. Decoder


26


decodes such coded digital video signals as reproduced from storage medium


40


to produce uncoded digital video signals which are coupled to video display


105


for display. It is preferred that decoder


26


is adapted to decode digital video signals encoded in accordance with the Moving Picture Image Coding Experts Group (MPEG) standard.




Clock


27


is comprised of a clock device and a date device for tracking the time of day and the calendar date, respectively, known to those of ordinary skill in the art. Clock


27


is coupled to access controller


28


A and supplies time signals and date signals thereto. The clock receives a time reference signal and a date reference signal from descrambler


21


A and synchronizes its operation therewith.




User interface


30


is coupled to access controller


28


A and supplies user input signals thereto. The user input signals are generated as a function of input supplied by a user to the user interface which may include a keyboard or user-operated switches. Typical user input signals include a command to display video signals, a command to record broadcast video signals, an authorization code, a request for a specific video program, and so on.




Modem


31


is coupled to access controller


28


A and to communication link


106


and facilitates the communication of signals through the communication link between broadcasting station


101


(shown in

FIG. 1

) and the access controller. As communication link


106


is preferably a telephone line, modem


31


is preferably a conventional telephone line modem.




Access controller


28


A is further coupled to an access condition memory


29


. It will be appreciated that, as a function of the signals supplied to access controller


28


A by clock


27


, user interface


30


, modem


31


, and access condition memory


29


, the access controller controls the operation of encipherer


22


and decipherer


25


. As will be discussed in greater detail below, depending upon whether applicable conditions have been fulfilled, the access controller enables or disables the operation of encipherer


22


and decipherer


25


. Access controller


28


A stores access-control signals in and retrieves access-control signals from access condition memory


29


. In an alternate embodiment, it is contemplated that the access controller


28


A stores both access-control signals and the encryption keys of encipherer


22


and decipherer


25


in access condition memory


29


.




Access-control signals indicate the conditions, if any, to be placed on the reproduction of the video component of the selected digital video signals. These conditions describe the circumstances under which a user may or may not reproduce the selected video signals. As a function of the access-control signals, the selected video signals recovered by descrambler


21


A are processed prior to recording and processed again following reproduction. Depending on the particular conditions and circumstances, a user can be prevented entirely from accessing the selected digital video signals, given limited access to the signals, or given full access to the signals. Such conditions may include, but are not limited to, one or more of the following: (1) previous receipt of a payment signal from broadcasting station


101


, (2) a numerical limit on the number of times particular video signals may be reproduced or displayed, (3) a temporal limit on the reproduction or display of video signals, and (4) previous receipt of a user authorization code. Preferably, the access-control signals are comprised of simple default values.




Also illustrated in

FIG. 2

is storage cassette


104


A which comprises access condition memory


29


and storage medium


40


. Storage cassette


104


A is, as a whole, removably connected to receiving system


102


A. Access condition memory


29


stores access-control signals indicating the conditions, if any, to be placed on the reproduction and/or recording of video signals on storage medium


40


. Preferably, access condition memory


29


is an integrated circuit RAM, integrated into storage cassette


104


A but independent of storage medium


40


, as has been proposed heretofore, and electrically connectable to access controller


28


A. Storage medium


40


stores signals recorded thereon by head


24


and is preferably removably engaged therewith.




Operation of the embodiment of the controlled-access broadcast digital video signal receiving system


102


A shown in

FIG. 2

will be described below. An important feature of this embodiment is that access-control signals, corresponding to video signals that are to be recorded on or reproduced from storage medium


40


, are stored in access condition memory


29


. Access controller


28


A controls the operation of encipherer


22


and decipherer


25


as a function of one or more of the access-control signals stored in access condition memory


29


and/or received from modem


31


. In this manner, the encryption and decryption of video signals is controlled to prevent unauthorized reproduction of the video signals.




The configuration of the present invention is compatible with many different sequences of signal transfer between broadcasting station


101


and receiving system


102


A. Examples of useful signal transfer sequences, implemented in different modes of operation of the present invention, will be described in detail below. Through the different modes of operation, video programs are securely transferred between a broadcaster and a consumer for recording, but the consumer's ability to display the programs can be subjected to limitations.




In a first video-on-demand mode, a user enters into user interface


30


a request for a specific video program. User interface


30


transmits this request to access controller


28


A, which, in turn, communicates the user's request through modem


31


and communication link


106


to broadcasting station


101


. The broadcasting station transmits the requested video program to satellite


107


which relays the video program to antenna


103


and supplies the video signals representing this program to tuner


20


. It is expected that several video signals are coupled to tuner


20


, which selects the particular video signals comprising the requested video program and supplies these selected video signals to descrambler


21


A. The descrambler descrambles these broadcast video signals and supplies a descrambled version of the video signals to encipherer


22


. Descrambler


21


A also supplies a time reference signal and a date reference signal, which accompany the video program transmission, to clock


27


.




Additionally, broadcasting station


101


communicates access-control signals through communication link


106


and modem


31


to access controller


28


A for storage in access condition memory


29


. The access-control signals serve to define the conditions or limitations, if any, upon the usage of the requested video program. In general, a user can either purchase or rent a particular video program from a broadcaster. In a prepayment method of purchase, a user pays for a video program and subsequently requests that the broadcaster transmit the program to the user's video receiving system. Broadcasting station


101


transmits the requested program and an access-control signal indicating that the video program can be unconditionally recorded and reproduced (FULL ACCESS). Access controller


28


A stores the FULL ACCESS signal in access condition memory


29


to disable encipherer


22


. Hence, descrambled video signals of the video program are supplied by descrambler


21


A through encipherer


22


, without encryption, to recording/reproducing section


23


A, whereat the descrambled and unencrypted video signals are recorded on storage medium


40


.




In a postpayment method of purchase, wherein a user elects to pay for a video program after it has been received by the user's receiving system, broadcasting station


101


transmits the particular video program to receiving system


102


A along with an access-control signal indicating that the video program cannot be reproduced (NO REPRO). Access controller


28


A stores the NO REPRO signal in access condition memory


29


and enables encipherer


22


, causing it to encrypt, according to an encryption key, descrambled video signals of the video program supplied by descrambler


21


A. Encipherer


22


supplies encrypted video signals to recording/reproducing section


23


A, whereat the encrypted video signals are recorded on storage medium


40


.




It is contemplated that the user subsequently purchases the video program from the broadcaster. Upon payment, broadcasting station


101


transmits an access-control signal to access controller


28


A indicating that the recorded video program can be reproduced (REPRO OK), and this REPRO OK signal replaces the previously stored NO REPRO signal in memory


29


. When the encrypted video signals subsequently are played back from storage medium


40


, they are supplied to decipherer


25


which is enabled by the stored REPRO OK signal to decrypt the reproduced video signals.




In a second prepayment method of purchase, similar to the postpayment method, the user pays for the selected program prior to its transmission, but broadcasting station


101


first transmits the selected program to receiving system


102


A along with a NO REPRO signal. Access controller


28


A causes encipherer


22


to encrypt the video signals of the video program and the encrypted signals are recorded on storage medium


40


while the NO REPRO signal is stored in access condition memory


29


. Upon completion of the video program transmission, broadcasting station


101


transmits a REPRO OK signal; and access controller


28


A replaces the stored NO REPRO signal with the REPRO OK signal. Thus, the video program is recorded in encrypted form but the user can reproduce and decrypt the program an unlimited number of times. This second prepayment method has the advantage of producing video recordings that can only be reproduced in devices having compatible decryption capabilities.




Alternatively, a user can purchase the right to reproduce a video program a certain number (N) of times. The user thus “rents” the video program for N reproductions. In one mode, the user enters a request into user interface


30


to rent a video program for N reproductions. User interface


30


transmits the request to access controller


28


A which forwards the request through modem


31


and communication link


106


to broadcasting station


101


. Broadcasting station


101


transmits the requested video program along with an access-control signal indicating that the video program can only be reproduced N times (REPRO N TIMES). The access controller receives the REPRO N TIMES signal and stores it in access condition memory


29


. The video program is received by tuner


20


and supplied to descrambler


21


A which descrambles the video program and supplies descrambled video signals to encipherer


22


. The encipherer, which is enabled by the access controller, encrypts the descrambled video signals, and supplies encrypted signals to recording/reproducing section


23


A for recording on storage medium


40


.




In another rental mode, wherein a user desires to rent a particular video program for a certain period of time, an access-control signal designating the period of time during which reproduction of the requested video program is authorized is supplied by the broadcasting system. For example, the user may request to rent a particular video program for a certain number of days (D). Receiving system


102


A transmits this request via communication link


106


to broadcasting station


101


. The broadcasting station calculates the date Y, as a function of D, on which the reproduction right should expire, and transmits the requested video program along with an access-control signal indicating that reproduction is allowed until date Y (REPRO UNTIL DATE Y). The access-control signal is received by receiving system


102


A and stored in access condition memory


29


. The access controller enables the operation of encipherer


22


; and as described above, the requested video program is received, selected by tuner


20


, descrambled, enciphered, and recorded in enciphered form. Subsequently, the encrypted video program is reproduced, deciphered (so long as the reproduction operation is performed prior to date Y) and displayed.




As another example, a user can request to rent a particular video program for a certain number of hours (H). Receiving system


102


A transmits this request via communication link


106


to broadcasting station


101


which calculates the time T, as a function of H, when the reproduction right should expire, and transmits the requested video program along with an access-control signal indicating that reproduction is allowed until time T (REPRO UNTIL TIME T). The received access-control signal is stored in access condition memory


29


; and the operation of encipherer


22


is enabled by access controller


28


A. As described above, the requested video program is received, selected, descrambled, enciphered, and recorded in an enciphered form.




Of course, there are many different methods of expressing the terms of a rental. The preceding expressions are intended merely as examples to assist in explaining the present invention and not as limits thereon. Further examples of useful rental terms include: reproduction of a video program for a certain number of hours or of days, or for a period of time in the future.




Analogous to the prepayment and postpayment methods of purchase, each rental of a video program can be prepaid or postpaid by the user. When the rental is prepaid, broadcasting station


101


transmits the requested program and the access-control signal specifying the terms of the rental to receiving system


102


A which processes the video program (i.e., selectively encrypts the video signals) and stores the access-control signal as described above.




In contrast, when the rental is postpaid, broadcasting station


101


transmits the requested program and a NO REPRO signal to receiving system


102


A, which encrypts and records the video program and stores the NO REPRO signal as described above. Upon proper payment, broadcasting station


101


transmits the access-control signal specifying the terms of the rental to the receiving system which replaces the NO REPRO signal in access condition memory


29


with the newly-transmitted access-control signal.




In a further variation, a certain segment of the video program can be made available for reproduction by a user in a “preview” mode of operation. In this “preview” mode a user can view a selected portion of the requested video program and later decide whether or not to purchase or rent the entire video program. In an illustrative implementation of the preview mode, the access-control signal corresponding to the preview segment is a REPRO OK signal and the access-control signal corresponding to the entire video program is a NO REPRO signal.




In a second video-on-demand mode, a user requests video programming from a broadcaster to be transmitted at a later time, perhaps the following day. The video programming may be, for example, one or more video programs selected by the user or a number of video programs selected by the broadcaster. In the latter case, it is contemplated that the user initially selects a particular type of video programming or selects video programming provided by a particular video program supplier.




The request for “delayed” transmission of the video programming is entered by the user into user interface


30


. User interface


30


transmits this request to access controller


28


A which communicates the user's request through modem


31


and communication link


106


to broadcasting station


101


.




Some period of time later, broadcasting station


101


transmits the requested video programming to satellite


107


which relays the video programming to antenna


103


. Preferably, transmission of the video programming occurs during periods when broadcasters are “off-the-air” or during periods of low viewership of broadcast video signals. Antenna


103


receives the video programming and supplies the video signals to tuner


20


from which the particular video signals comprising the requested video programming are supplied to descrambler


21


A which, in turn, supplies a descrambled version of the video signals to encipherer


22


.




In this mode, broadcasting station


101


also transmits two access-control signals via communication link


106


and modem


31


to access controller


28


A. One access-control signal indicates that the video programming is to be erased on a certain date Y (ERASE ON DATE Y) and the other access-control signal is the NO REPRO signal. Access controller


28


A stores the ERASE ON DATE Y signal and the NO REPRO signal in access condition memory


29


. Encipherer


22


, when enabled, supplies encrypted video signals to recording/reproducing section


23


A for recording on storage medium


40


.




Subsequently, but prior to date Y, the user selects a video program from the requested video programming stored on storage medium


40


and pays the fee to rent the selected program for a particular rental term. Upon payment, broadcasting station


101


transmits the access-control signal indicating the appropriate rental condition to access controller


28


A which replaces the previously stored NO REPRO signal in memory


29


. Hence, the ERASE ON DATE Y signal remains stored in access condition memory


29


.




Illustrative video signal reproduction modes of operation of receiving system


102


A now will be described. The process is initiated when a user enters a command into user interface


30


to reproduce a prestored video program recorded on storage cassette


104


A. The user interface transmits the command to access controller


28


A which retrieves the access-control signal stored in access condition memory


29


of the storage cassette. The operation of decipherer


25


is controlled as a function of the particular access-control signal(s) that is retrieved.




If, for example, the retrieved signal is a FULL ACCESS signal, then access controller


28


A disables decipherer


25


. Recording/reproducing section


23


A recovers video signals from storage medium


40


and supplies the reproduced video signals to decipherer


25


, which passes the video signals to decoder


26


. As described above, the reproduced video signals are unencrypted; and decoder


26


decodes the video signals and supplies uncoded video signals to video display


105


.




If the NO REPRO signal is retrieved from access condition memory


29


, access controller


28


A disables the operation of decipherer


25


. However, unlike the FULL ACCESS signal case, the video signals stored on storage medium


40


are encrypted. Hence, recording/reproducing section


23


A reproduces encrypted video signals which are supplied to decipherer


25


to be passed directly to decoder


26


without decryption. The decoder decodes the encrypted video signals to produce uncoded but encrypted video signals which are supplied to video display


105


. As a result, the video display either cannot display the video signals at all or can only display a distorted version of the original video program.




As a further alternative, access controller


28


A may retrieve a REPRO OK signal from access condition memory


29


to enable the operation of decipherer


25


. Recording/reproducing section


23


A reproduces the encrypted video signals stored on storage medium


40


and supplies the encrypted signals to enabled decipherer


25


which decrypts the video signals and supplies unencrypted video signals to decoder


26


. The decoder decodes the video signals and supplies the resulting uncoded and decrypted video signals to video display


105


for display. Because the video signals are uncoded and decrypted, video display


105


displays the reproduced video program without distortion.




As yet another alternative, when access controller


28


A retrieves a REPRO N TIMES signal from access condition memory


29


, the access controller


28


A determines whether the number N is greater than a predetermined threshold value (e.g. zero). If the number N is not greater than the threshold value, then access controller


28


A disables operation of decipherer


25


and reproduction of the stored video signal proceeds as in the NO REPRO signal case. On the other hand, if the number N is greater than the threshold value, then access controller


28


A enables decipherer


25


and reproduction of the stored video signal proceeds as in the REPRO OK signal case.




After the video signal is reproduced from storage medium


40


, if the number N is greater than the threshold value, access controller


28


A subtracts one from the value of N to produce a new value N and writes a new REPRO N TIMES signal, utilizing the new value N, into access condition memory


29


whereat the previously stored REPRO N TIMES signal is replaced by the new REPRO N TIMES signal. According to this procedure, the particular video signals stored in storage medium


40


to which the REPRO N TIMES signal corresponds are only reproduced the number of times represented by the number N. The value N stored in access condition memory


29


thus reflects the remaining number of permitted reproductions of the particular video signals. Since the access condition memory is provided in the same storage cassette


104


A as storage medium


40


, and the video signals are encrypted on the storage medium, the video signals can only be reproduced for display N times even if the cassette is loaded into another receiving system, at least until a new access-control signal is stored.




When, as described above, a video program is rented for only a certain period of time, access controller


28


A retrieves the corresponding access-control signal from access condition memory


29


and also receives a clock signal and a date signal from clock


27


. The clock signal and the date signal are compared to the retrieved access-control signal, and if the particular condition expressed in the access-control signal is satisfied such that reproduction is allowed, then decipherer


25


is enabled and reproduction of the stored video signals proceeds as in the REPRO OK case. However, if the condition expressed by the access-control signal is not satisfied such that reproduction of the video signals is not allowed, then the decipherer is disabled and reproduction of the stored video signals proceeds as described with respect to the NO REPRO signal.




For example, when access controller


28


A retrieves a REPRO UNTIL DATE Y signal from access condition memory


29


, it compares the date signal from clock


27


to the date Y. If the date from clock


27


is prior to date Y, then the access controller enables the operation of decipherer


25


to decrypt the reproduced, encrypted video signals. In a similar fashion, when the access controller retrieves a REPRO UNTIL TIME T signal from the access condition memory, it compares the time signal supplied by clock


27


with the time T. If the time indicated by the time signal is prior to time T, then reproduction of the stored video signals proceeds as described with respect to the REPRO OK signal.




In an analogous manner, when access controller


28


A retrieves an ERASE ON DATE Y signal from access condition memory


29


, it compares the date signal from clock


27


to the date Y. If the date indicated by clock


27


is the same as or past date Y, then the access controller controls recording/reproducing section


23


A to erase the video signals stored on storage medium


40


. A suitable control channel, or link, may be provided between access controller


28


A and recording/reproducing section


23


A.




An alternate embodiment of receiving system


102


A additionally includes a connection between descrambler


21


A and access controller


28


A. Here, scrambled access-control signals that are transmitted by broadcasting station


101


along with the video signals are supplied to and descrambled by descrambler


21


A from which they are coupled to the access controller. In this alternate embodiment, video signals are recorded and reproduced as described above, and encipherer


22


and decipherer


25


are selectively enabled and disabled in response to the received access-control signals in the same manner as has been discussed.




As will be appreciated by one of ordinary skill in the art, each of the abovedescribed modes of signal reproduction wherein the user has prepaid for the video programming can be achieved substantially simultaneously with the recording of the broadcast video signals. In such a mode of operation, recording/reproducing section


23


A functions both to record the processed broadcast video signals and to supply the video signals to decipherer


25


. Decipherer


25


, controlled by access controller


28


A, decrypts the video signals as a function of the access-control signal to be stored in access condition memory


29


and decoder


26


decodes the resulting video signals for immediate display on video display


105


.




Another embodiment of the controlled-access broadcast digital video signal receiving system


102


B according to the present invention is illustrated in FIG.


3


. Receiving system


102


B differs from aforedescribed receiving system


102


A in that receiving system


102


B stores access-control signals and video signals in the same storage medium


40


of storage cassette


104


B.




Recording/reproducing section


23


B, through head


24


, records on storage medium


40


in storage cassette


104


B video signals supplied by encipherer


22


and access-control signals supplied by access controller


28


B; and also reads previously recorded video signals and previously recorded access-control signals from the storage medium. The reproduced video signals are supplied to decipherer


25


and the reproduced access-control signals are supplied from the recording/reproducing section to access controller


28


B. As before, recording/reproducing section


23


B is a digital video tape recording/reproducing device (VTR) and storage medium


40


is a video tape; although the storage medium may be a magnetic disc, an optical disc, a magneto-optic disc, a solid-state device, or other recordable medium. It is also preferred that the access-control signals be stored in one or more sub-code regions of the storage medium.




When enabled by access controller


28


B, decipherer


25


decrypts, according to an encryption key, encrypted signals reproduced by recording/reproducing section


23


B. It is contemplated that the encryption key is prestored in the decipherer or is supplied thereto by access controller


28


B, or is included in the video signals or the access-control signals supplied by broadcasting station


101


, or is stored in and read from storage medium


40


. When disabled, decipherer


25


passes video signals from recording/reproducing section


23


B directly to decoder


26


without decrypting such signals.




As a function of the signals supplied to access controller


28


B by clock


27


, user interface


30


, modem


31


, and recording/reproducing section


23


B, the access controller controls the operation of encipherer


22


and decipherer


25


as has been described previously. Specifically, depending upon whether applicable conditions have been fulfilled, the access controller enables or disables the operation of encipherer


22


and decipherer


25


.




Each signal transfer sequence, including variations thereon, described above with respect to receiving system


102


A is also implemented in similar modes of operation of receiving system


102


B. It will be appreciated, then, that the modes of operation of receiving system


102


B are substantially identical to the modes of operation of receiving system


102


A with the following illustrative exceptions. Access controller


28


B functions in the same manner as access controller


28


A, except that access-control signals are stored, through recording/reproducing section


23


B, in storage medium


40


, instead of in a separate access condition memory. Recording/reproducing section


23


B functions in the same manner as section


23


A except that section


23


B additionally records access-control signals on and reproduces access-control signals from storage medium


40


. The reproduced access-control signals are supplied from recording/reproducing section


23


B to access controller


28


B.




Similar to the alternate embodiment discussed in conjunction with

FIG. 2

, an alternate embodiment of receiving system


102


B additionally includes a connection between descrambler


21


A and access controller


28


B so that scrambled access-control signals that are transmitted by broadcasting station


101


along with the video signals are descrambled and supplied to the access controller. Of course, access controller


28


B uses these access-control signals in the same manner as discussed above.




A further embodiment of the controlled-access broadcast digital video signal receiving system


102


C according to the present invention is illustrated in FIG.


4


. Receiving system


102


C, is adapted for receiving, descrambling, decoding, recording, and reproducing digital video signals and is similar to the aforedescribed receiving system


102


A of FIG.


2


. As in receiving system


102


A, receiving system


102


C stores access-control signals in access condition memory


29


of storage cassette


104


A, while the video signals are stored on storage medium


40


of the storage cassette.





FIG. 4

differs from

FIG. 2

in that descrambler


21


C of receiving system


102


C is coupled to access controller


28


C, recording/reproducing section


23


A, and decoder


26


; and encipherer


22


and decipherer


25


are not provided as separate circuits. When enabled by access controller


28


C, descrambler


21


C descrambles video signals supplied by tuner


20


and supplies an unscrambled version of the digital video signals to recording/reproducing section


23


A. Also, when enabled by the access controller, descrambler


21


C descrambles video signals reproduced by recording/reproducing section


23


A and supplies an unscrambled version of the digital video signals to decoder


26


. When disabled by access controller


28


C, descrambler


21


C passes scrambled video signals from tuner


20


directly, without encryption, to section


23


A and also passes video signals reproduced by the recording/reproducing section directly, without decryption, to decoder


26


. Scrambled video signals can be recorded but they cannot be displayed in scrambled form.




It will be appreciated that access controller


28


C functions in the same general manner as access controller


28


A, except that descrambler


21


C is controlled in accordance with the access-control signals rather than encipherer


22


and decipherer


25


.




At those aforedescribed operational steps where access controller


28


A enables encipherer


22


, access controller


28


C disables descrambler


21


C to pass scrambled signals to the recording/reproducing section; and where access controller


28


A disables encipherer


22


, access controller


28


C enables descrambler


21


C to supply descrambled signals to the recording/reproducing section. However, in the operational steps where access controller


28


A enables decipherer


25


, access controller


28


C similarly enables descrambler


21


C to descramble the signals reproduced by the recording/reproducing section. Where access controller


28


A disables decipherer


25


, access controller


28


C similarly disables descrambler


21


C to pass to decoder


26


signals reproduced by the recording/reproducing section.




In an alternate embodiment of receiving system


102


C, access-control signals, transmitted by broadcasting station


101


along with video signals, are received through antenna


103


and supplied by tuner


20


to descrambler


21


C for descrambling and for coupling to access controller


28


C.




A still further embodiment of the controlled-access broadcast digital video signal receiving system


102


D according to the present invention is illustrated in FIG.


5


. Receiving system


102


D is seen to be a combination of portions of receiving system


102


C and receiving system


102


B (FIG.


3


). Similar to receiving system


102


B, receiving system


102


D stores access-control signals and video signals in the same storage medium


40


of storage cassette


104


B. Recording/reproducing section


23


B supplies the reproduced video signals to descrambler


21


C and supplies the reproduced access-control signals to access controller


28


D.




It will be appreciated that the modes of operation of receiving system


102


D are substantially similar to the modes of operation of receiving system


102


C with the following illustrative exceptions. Access controller


28


D functions in the same manner as access controller


28


C, except that access-control signals are stored in storage medium


40


instead of in a separate access condition memory. Recording/reproducing section


23


B functions in the same manner as section


23


A except that section


23


B additionally records access-control signals on and reproduces access-control signals from storage medium


40


. The reproduced access-control signals are supplied from recording/reproducing section


23


B to access controller


28


D.




Similar to the alternate embodiment discussed in conjunction with

FIG. 4

, access-control signals, transmitted by broadcasting station


101


along with video signals, are received through antenna


103


and supplied by tuner


20


to descrambler


21


C for descrambling; and the descrambled access-control signals are supplied to access controller


28


D. It is seen that access controller


28


D receives access-control signals from recording/reproducing section


23


B and either from modem


31


or from descrambler


21


C, or from both.





FIG. 6

is a flow diagram of a preferred mode of operation of receiving system


102


A of

FIG. 2

, as controlled by access controller


28


A, wherein a user orders from a broadcaster a limited or an unlimited right (as may be desired) to reproduce a video program. The user initiates the process by entering a request for a particular video program at user interface


30


. The process begins at step S


60


, where access controller


28


A causes modem


31


to connect to broadcasting station


101


.




Access controller


28


A transmits identification information through modem


31


and communication link


106


to broadcasting station


101


which checks the identification information against a subscription list and determines whether the user has subscribed to the broadcasting station's service, as represented by inquiry S


61


. If the user is not subscribed, the broadcasting station terminates the connection with receiving system


102


A in step S


62


.




If the user is subscribed, inquiry S


61


is answered in the affirmative and operation continues to inquiry S


63


, which polls the user to determine whether or not the video program is to be purchased. If the user enters an affirmative response into user interface


30


, operation proceeds to inquiry S


64


. Otherwise, operation proceeds to inquiry S


65


.




At inquiry S


64


, the broadcasting station


101


determines whether the user has prepaid for the video program and if not, the user is further queried to determine if payment will be made at that time. If the price of the video program has been previously paid or is immediately paid, then processing proceeds with step S


66


. Otherwise, processing proceeds with step S


67


.




In step S


66


, broadcasting station


101


transmits the video program via satellite to antenna


103


and transmits the FULL ACCESS signal via communication link


106


and modem


31


to access controller


28


A. Access controller


28


A disables encipherer


22


, allowing the video program to be recorded in an unencrypted form on storage medium


40


, and the access controller also stores the FULL ACCESS signal in access condition memory


29


.




In step S


67


, broadcasting station


101


transmits the video program via satellite to antenna


103


and transmits the NO REPRO signal via communication link


106


and modem


31


to access controller


28


A. The access controller enables encipherer


22


, causing the video program to be encrypted and then recorded in encrypted form on storage medium


40


, and the NO REPRO signal is stored in access condition memory


29


.




If the video program is not to be purchased, resulting in a negative answer to inquiry S


63


, the operation proceeds to inquiry S


65


whereat the user is polled to determine whether the video program is to be rented for a number (N) of viewings. If the user enters an affirmative response into user interface


30


, the number N is entered, and operation proceeds to inquiry S


69


. Otherwise, operation proceeds to inquiry S


68


.




At inquiry S


69


, the broadcasting station


101


determines whether the user has prepaid for the N viewings of the video program and if not, the user is further queried to determine if payment will be made at that time. If the fee for N viewings of the video program has been previously paid or is immediately paid, processing proceeds with step S


71


. Otherwise, processing proceeds with step S


72


.




In step S


71


, broadcasting station


101


transmits the video program via satellite to antenna


103


and transmits the REPRO N TIMES signal via communication link


106


and modem


31


to access controller


28


A. The access controller


28


A enables encipherer


22


, causing the video program to be encrypted and then recorded on storage medium


40


; and the REPRO N TIMES signal is stored in access condition memory


29


.




In step S


72


, broadcasting station


101


transmits the video program via satellite to antenna


103


and transmits the NO REPRO signal via communication link


106


and modem


31


to access controller


28


A. The access controller enables encipherer


22


, causing the video program to be encrypted and then recorded on storage medium


40


; and the NO REPRO signal is stored in access condition memory


29


.




If the video program is not to be rented for N viewings, inquiry S


65


is answered in the negative and the operation proceeds to inquiry S


68


whereat the user is polled to determine whether a video program is to be rented for viewing until a date Y. If the user enters an affirmative response into user interface


30


, the date Y is entered, and operation proceeds to inquiry S


70


. Otherwise, operation returns step S


62


, described above.




At inquiry S


70


, the broadcasting station


101


determines whether the user has prepaid for the rental of the video program until date Y and if not, the user is further queried to determine if payment will be made at that time. If the fee for the rental period has been previously paid or is immediately paid, then processing proceeds with step S


73


. Otherwise, processing proceeds with step S


72


, described above.




In step S


73


, broadcasting station


101


transmits the video program via satellite to antenna


103


and transmits the REPRO UNTIL DATE Y signal via communication link


106


and modem


31


to access controller


28


A. The access controller enables encipherer


22


, causing the video program to be encrypted and then recorded in encrypted form on storage medium


40


. Access controller


28


A also stores the REPRO UNTIL DATE Y signal in access condition memory


29


.





FIG. 7

is a flow diagram of a preferred mode of operation of receiving system


102


A of

FIG. 2

wherein a user seeks to reproduce a selected previously recorded video program. The user initiates the process by supplying a request to reproduce a prerecorded video program at user interface


30


and the process begins at step S


80


, where access controller


28


A retrieves from access condition memory


29


the access-control signal corresponding to the selected video program. The process proceeds to inquiry S


81


whereat the access controller determines if the access-control signal is the NO REPRO signal. If so, processing proceeds with step S


86


; otherwise, processing proceeds to inquiry S


82


.




In step S


86


, access controller


28


A causes modem


31


to connect to broadcasting station


101


and transmits identification information and program information to the broadcasting station. Processing then proceeds to inquiry S


88


which queries the user to determine if payment of the full purchase price for the video program will be made at that time. If the purchase price of the video program is paid, then processing proceeds with step S


93


. Otherwise, processing proceeds to inquiry S


89


.




In step S


93


, broadcasting station


101


transmits the REPRO OK signal via communication link


106


and modem


31


to access controller


28


A which stores the REPRO OK signal in access condition memory


29


, replacing the NO REPRO signal, and processing proceeds to step S


97


. In step S


97


, the access controller enables decipherer


25


; and the selected video program which is reproduced from storage medium


40


is decrypted by decipherer


25


, decoded by decoder


26


, and supplied for display to video display


105


.




If the retrieved access-control signal is not the NO REPRO signal, as represented by a negative answer to inquiry S


81


, inquiry S


82


determines whether the access-control signal is the REPRO N TIMES signal. If so, processing proceeds with step S


94


. Otherwise, processing proceeds to inquiry S


83


. In step S


94


, access controller


28


A decrements N by one, debiting the single reproduction which will immediately follow. Further, the REPRO N−1 TIMES signal is stored in access condition memory


29


, replacing the access-control signal previously stored there, and processing proceeds to step S


97


to reproduce and decrypt the video signal, described above.




If the retrieved access-control signal is not the REPRO N TIMES signal, inquiry S


83


is made to determine if the access-control signal is the REPRO UNTIL DATE Y signal. If so, processing proceeds to inquiry S


87


. Otherwise, processing proceeds to inquiry S


84


. Inquiry S


87


compares the date signal supplied by clock


27


, indicating the current date, with date Y. If the current date is prior to date Y, then processing proceeds to step S


97


, described above. Otherwise, processing proceeds to step S


90


, whereat access controller


28


A determines that the applicable condition has not been satisfied and therefore no video signal reproduction is authorized. The access controller thereafter terminates the connection with broadcasting station


101


.




If the retrieved access-control signal is neither the NO REPRO nor the REPRO N TIMES nor the REPRO UNTIL DATE Y signal, inquiry S


84


determines if the access-control signal is the REPRO OK signal. If it is, processing proceeds with step S


97


, described above. Otherwise, processing advances to inquiry S


85


whereat access controller


28


A determines if the access-control signal is the FULL ACCESS signal. If so, processing proceeds with step S


96


. Otherwise, processing proceeds with step S


92


.




In step S


92


, access controller


28


A determines that it has failed to recognize the particular access-control signal stored in condition access memory


29


, if any. Lacking a recognizable access-control signal, no video signal reproduction is authorized. Access controller


28


A terminates the connection with broadcasting station


101


. It should be appreciated that step S


92


can be replaced with additional access-control signal definitions to provide further processing and access-control signal permutations.




In step S


96


, access controller


28


A disables decipherer


25


, and recording/reproducing section


23


A reproduces the selected video program from storage medium


40


. The reproduced video program passes through decipherer


25


for decoding by decoder


26


, and is supplied to video display


105


for display.




If the retrieved access-control signal is the NO REPRO signal and payment of the full purchase price is not made, inquiry S


88


is answered in the negative and the process advances to inquiry S


89


, which queries the user to determine if the fee for N viewings of the video program will be paid. If the fee for N viewings of the video program is paid, then broadcasting station


101


transmits the REPRO N TIMES signal via communication link


106


and modem


31


to access controller


28


A, and processing proceeds with step S


94


, described above. Otherwise, processing proceeds to inquiry S


91


which queries the user to determine if the fee for rental of the video program until date Y will be paid. If the fee for such a rental is paid, then processing proceeds with step S


95


. Otherwise, processing proceeds with step S


90


, described above.




In step S


95


, broadcasting station


101


transmits the REPRO UNTIL DATE Y signal via communication link


106


and modem


31


to access controller


28


A which stores the REPRO UNTIL DATE Y signal in access condition memory


29


, replacing the NO REPRO signal, and processing proceeds to step S


97


, described above.




Those of ordinary skill in the art will readily appreciate the modifications to be made to the flow diagrams of

FIGS. 6 and 7

to control the operation of the controlled-access broadcast video signal recording systems shown in

FIGS. 3

,


4


and


5


. Hence, in the interest of brevity, further description of such modified flow diagrams is not made.




Although illustrative embodiments of the present invention and modifications thereof have been described in detail herein, it is to be understood that this invention is not limited to these precise embodiments and modifications, and that other modifications and variations may be effected therein by one skilled in the art without departing from the scope and spirit of the invention as defined by the appended claims. For example, it is contemplated that a broadcast video program can be processed by an apparatus according to the present invention for display to a user without a preceding or simultaneous recording of the video program.



Claims
  • 1. Apparatus for receiving, recording, and reproducing data signals, comprising:receiving means for receiving said data signals and an access-control signal generated by a remote provider which grants users rights to reproduce said data signals; processing means, coupled to said receiving means, for processing said data signals to produce processed data signals; control means for controlling said processing means in response to said access-control signal; storage means for storing said processed data signals and for storing said access-control signal; means for reproducing said stored processed data signals to produce reproduced data signals and for retrieving said stored access-control signal; and reprocessing means coupled to said control means for reprocessing said reproduced data signals in response to said retrieved access-control signal.
  • 2. Apparatus according to claim 1 wherein said data signals are digital video data signals.
  • 3. Apparatus according to claim 1 wherein said receiving means receives said data signals and said access-control signal from a broadcasting station.
  • 4. Apparatus according to claim 1 wherein said receiving means further comprises a tuner for receiving broadcast signals.
  • 5. Apparatus according to claim 4 wherein said receiving means further comprises a modem for receiving said access-control signal.
  • 6. Apparatus according to claim 1 wherein said receiving means further comprises a modem for receiving said access-control signal.
  • 7. Apparatus according to claim 1 wherein said receiving means further comprises a user interface for receiving said access-control signal from a user.
  • 8. Apparatus according to claim 1 wherein said processing means comprises a descrambler.
  • 9. Apparatus according to claim 1 wherein said processing means comprises a descrambler and an encipherer and wherein said reprocessing means comprises a decipherer.
  • 10. Apparatus according to claim 1 wherein said processing means comprises an encipherer and wherein said reprocessing means comprises a decipherer.
  • 11. Apparatus according to claim 1 wherein said processed data signals are stored on a record medium and said access-control signal is stored in a separate storage medium.
  • 12. Apparatus according to claim 11 wherein said record medium is a video tape.
  • 13. Apparatus according to claim 11 wherein said separate storage medium is an integrated circuit memory.
  • 14. Apparatus according to claim 1 wherein said processed data signals and said access-control signal both are stored on a common record medium.
  • 15. Apparatus according to claim 1 further comprising a clock, coupled to said receiving means and to said control means, for supplying a clock signal to said control means;wherein said data signals include a clock reference signal; and wherein said clock signal is synchronized with said clock reference signal.
  • 16. Apparatus according to claim 1 further comprising a decoder, coupled to said reprocessing means, for decoding said reprocessed data signals.
  • 17. Apparatus for receiving and recording data signals, comprising:receiving means for receiving said data signals and an access-control signal generated by a remote provider which grants users rights to reproduce said data signals; processing means, coupled to said receiving means, for processing said data signals to produce processed data signals; control means for controlling said processing means in response to said access-control signal; and storage means for storing said processed data signals and said access-control signal.
  • 18. Apparatus according to claim 17 wherein said processing means comprises a descrambler.
  • 19. Apparatus according to claim 18 wherein said processing means further comprises an encipherer.
  • 20. Apparatus according to claim 17 wherein said processing means comprises an encipherer.
  • 21. Apparatus according to claim 17 wherein said storage means comprises a storage cassette.
  • 22. Apparatus according to claim 21 wherein said storage cassette contains a record medium on which said processed data signals are recorded and an integrated circuit memory in which said access-control signal is stored.
  • 23. Apparatus for reproducing processed data signals, comprising:means for reproducing stored processed data signals to produce reproduced data signals and for retrieving a stored access-control signal generated by a remote provider which grants users rights to reproduce said data signals; reprocessing means for reprocessing said reproduced data signals to produce reprocessed data signals; and control means for controlling said reprocessing means in response to said retrieved access-control signal.
  • 24. Apparatus according to claim 23 wherein said reprocessing means comprises a descrambler.
  • 25. Apparatus according to claim 23 wherein said reprocessing means comprises a decipherer.
  • 26. Apparatus according to claim 23 wherein said processed data signals and said access-control signals are stored in a storage cassette.
  • 27. A method for transferring from a broadcaster to a receiver a limited reproduction right in data, comprising the steps of:transmitting from said broadcaster to said receiver an access-control signal generated by a remote provider and said data, said access-control signal indicating said limited reproduction right; receiving, at said receiver, said access-control signal and said data; processing, at said receiver, said data in response to said access-control signal to produce processed data; storing, at said receiver, said processed data and said access-control signal; retrieving, at said receiver, said stored access-control signal; reproducing, at said receiver, said stored processed data to produce reproduced data; and reprocessing, at said receiver, said reproduced data in response to said retrieved access-control signal.
  • 28. The method, according to claim 27, wherein said limited reproduction right is the right to reproduce said data N times.
  • 29. The method, according to claim 27, wherein said limited reproduction right is the right to reproduce said data until date Y.
  • 30. The method, according to claim 27, wherein said limited reproduction right is the right to reproduce said data until time T.
  • 31. The method, according to claim 27, wherein said data is transmitted in scrambled form and said step of processing said data comprises descrambling said data.
  • 32. The method, according to claim 31, wherein said step of processing said data further comprises enciphering said data; andwherein said step of reprocessing said reproduced data comprises deciphering said reproduced data.
  • 33. The method, according to claim 27, wherein said step of processing said data comprises enciphering said data; andwherein said step of reprocessing said reproduced data comprises deciphering said reproduced data.
  • 34. The method, according to claim 27, wherein said data is transmitted and stored in scrambled form, and said step of reprocessing said reproduced data comprises descrambling said reproduced data.
  • 35. The method, according to claim 27, wherein said processed data and said access-control signal are stored on a storage cassette.
  • 36. A method for transferring from a broadcaster to a receiver a limited reproduction right in prerecorded data, comprising the steps of:transmitting from said broadcaster to said receiver an access-control signal generated by a remote provider, said access-control signal indicating said limited reproduction right; receiving, at said receiver, said access-control signal; reproducing, at said receiver, said prerecorded data; and processing, at said receiver, said reproduced data in response to said access-control signal.
  • 37. The method, according to claim 36, wherein said step of processing said reproduced data comprises deciphering said reproduced data.
  • 38. The method, according to claim 36, wherein said step of processing said reproduced data comprises descrambling said reproduced data.
  • 39. A method for reproducing prerecorded data comprising the steps of:reproducing an access-control signal generated by a remote provider which grants users rights to reproduce said data signals from a first storage medium; reproducing processed data from a second storage medium in response to said access-control signal to produce reproduced data; and reprocessing said reproduced data in response to said access-control signal.
  • 40. A method for erasing prerecorded data stored on a record medium in response to an access-control signal stored in a separate memory, comprising the steps of:retrieving said access-control signal from said separate memory; determining that said access-control signal is an ERASE signal; and erasing data stored on said record medium in response to said ERASE signal.
  • 41. An apparatus for receiving one or more encrypted data signals to be recorded on a recording medium, comprising:a receiver for receiving said one or more encrypted data signals; a decryptor, coupled to said receiver, for decrypting said one or more received encrypted data signals; and an encryptor coupled to said decryptor for re-encrypting said one or more decrypted data signals to produce re-encrypted data signals that are reproducible based upon a received access control signal generated by a remote provider which grants a user rights to produce said data signals.
  • 42. The apparatus of claim 41, further comprising:a reproducing device for reproducing said one, or more re-encrypted data signals; and a second decryptor for decrypting said reproduced one or more re-encrypted data signals.
  • 43. The apparatus of claim 41, wherein said one or more re-encrypted data signals are recorded on said recording medium.
  • 44. The apparatus of claim 43, further comprising:a reproducing device for reproducing said one or more re-encrypted, data signals from said recording medium; a second decryptor for decrypting said reproduced one or more re-encrypted data signals; and a playback device for playing back said decrypted one or more re-encrypted data signals.
  • 45. The apparatus of claim 44, wherein said reproducing device reproduces said one or more re-encrypted data signals from said recording medium in accordance with an instruction received by said apparatus for receiving encrypted data signals.
  • 46. A method for receiving one or more encrypted data signals to be recorded on a recording medium, comprising the steps of:receiving said one or more encrypted data signals; decrypting said one or more received encrypted data signals; and re-encrypting said one or more decrypted data signals to produce re-encrypted data signals that are re-producible based upon a received access control signal generated by a remote provider which grants a user rights to produce said data signals.
  • 47. The method of claim 46, further comprising the steps of:reproducing said one or more re-encrypted data signals; and decrypting said reproduced one or more re-encrypted data signals.
  • 48. The method of claim 46, further comprising the step of recording said one or more re-encrypted data on said recording medium.
  • 49. The method of claim 48, further comprising the steps of:reproducing said one or more re-encrypted data signals from said recording medium; decrypting said reproduced one or more re-encrypted data signals; and playing back said decrypted one or more re-encrypted data signals.
  • 50. The method of claim 49, wherein said re-encrypted data is reproduced from said recording medium upon receipt of an instruction directing such reproducing.
  • 51. A method for controlling reproduction of data signals stored on a recording medium, comprising the steps of:retrieving an access control signal generated by a remote provider which grants a user rights to reproduce said data signals and which represents the number of times said data signals are permitted to be reproduced; reproducing said data signals from said recording medium, wherein said data signals are stored in an encrypted form; decrypting said reproduced data signals; and controlling the reproduction and decryption of said data signals in response to said retrieved access control signal.
  • 52. The method of claim 51, wherein said data signals are compressed signals and further comprising the step of decoding the decrypted data signals.
  • 53. The method of claim 51, wherein the access control signal is retrieved over a communication channel.
  • 54. The method of claim 51, wherein the access control signal is retrieved by reproducing said access control signal from said recording medium.
  • 55. The method of claim 51, wherein the access control signal is rewritable.
  • 56. A method for controlling reproduction of data signals stored on a recording medium, comprising the steps of:retrieving an access control signal generated by a remote provider which grants a user rights to reproduce said data signals and which represents a temporal limit on which said data signals are permitted to be reproduced; reproducing said data signals from said recording medium, wherein said data signals are stored in an encrypted form; decrypting said reproduced data signals; and controlling the reproduction and decryption of said data signals in response to said retrieved access control signal.
  • 57. The method of claim 56, wherein said data signals include clock reference data for adjusting the time of a clock used in reproducing said data signals.
  • 58. The method of claim 56, wherein said data signals are compressed signals, and further comprising the step of decoding the decrypted data signals.
  • 59. The method of claim 56, wherein the access control signal is retrieved over a communication channel.
  • 60. The method of claim 56, wherein the access control signal is retrieved by reproducing said access control signal from said recording medium.
  • 61. A method for transferring and receiving data signals, comprising the steps of:transferring said data signals to a receiver; transferring an access control signal generated by a remote provider to said receiver, the access control signal granting a user rights to reproduce said data signals at the receiver and representing the number of times said data signals are permitted to be reproduced; receiving said transferred data signals at the receiver; storing said received data signals in an encrypted form; receiving said transferred access control signal at the receiver; and storing said received access control signal.
  • 62. The method of claim 61, wherein said data signals and said access control signal are transferred to said receiver from the same remote provider.
  • 63. The method of claim 61, wherein said data signals and said access control signal are transferred to said receiver over different communication paths.
  • 64. The method of claim 61, wherein said data signals and said access control signal are transferred to said receiver over the same communication path.
  • 65. A method, for transferring and receiving data signals, comprising the steps of:transferring said data signals to a receiver; transferring an access control signal generated by a remote provider to said receiver, the access control signal granting a user rights to reproduce said data signals at the receiver and representing a temporal limit on which said data signals are permitted to be reproduced; receiving said transferred data signals at the receiver; storing said received data signals in an encrypted form; receiving said transferred access control signal at the receiver; and storing said received access control signal.
  • 66. The method of claim 65, wherein said data signals and said access control signal are transferred to said receiver from the same remote provider.
  • 67. The method of claim 65, wherein said data signals and said access control signal are transferred to said receiver over different communication paths.
  • 68. The method of claim 65, wherein said data signals and said access control signal are transferred to said receiver over the same communication path.
  • 69. A method for controlling reproduction of data signals stored on a recording medium, comprising the steps of:retrieving a first access control signal generated by a remote provider and stored on said recording medium together with said data signals, said first access control signal granting a user rights to reproduce the data signals from the recording medium; rewriting said first access control signal to produce a second access control signal; and reproducing said data signals from said recording medium.
  • 70. The method of claim 69, wherein at least one of said access control signals represents the number of times said data signals are permitted to be reproduced.
  • 71. A method for transferring data signals, comprising the steps of:receiving from a receiver a request for a desired data signal; receiving from said receiver a request for limited rights to use said requested data signal at the receiver; transferring said requested data signal to said receiver; and transferring to said receiver an access control signal that is generated as a function of said requested limited rights.
  • 72. The method of claim 71, wherein said access control signal represents the number of times said data signals are permitted to be used.
  • 73. The method of claim 71, wherein said access control signal represents a temporal limit on which said data signals are permitted to be used.
  • 74. A method for receiving data signals comprising the steps of:requesting a desired data signal; requesting limited rights to use said requested data signal; receiving said requested data signal; receiving an access control signal that is generated by a remote provider as a function of said requested limited rights; using said received data signal; controlling the use of said data signal in response to said received access control signal; and storing said received data signal in an encrypted form.
  • 75. The method of claim 74, wherein said access control signal represents the number of times said data signals are permitted to be used.
  • 76. The method of claim 74, wherein said access control signal represents a temporal limit on which said data signals are permitted to be used.
  • 77. The method of claim 74, wherein said access control signal defines one or more of the number of times said data signals are permitted to be used and a temporal limit on which said data signals are permitted to be used.
  • 78. The method of claim 74, wherein said step of using said received data signal comprises decrypting said received data signal.
  • 79. A method for controlling the reproduction of data signals, comprising the steps of:storing data signals received via a signal transmission medium; storing an access control signal received via said signal transmission medium, said access control signal being generated by a remote provider to grant a user rights to reproduce said stored data signals, and said access control signal defining one or more of the number of times said stored data signals are permitted to be reproduced and a temporal limit on which said stored data signals are permitted to be reproduced; checking the stored access control signal prior to reproducing the stored data signals to determine if said data signals are permitted to be reproduced; reproducing said stored data signals dependent upon said access control signal; and outputting to a monitor, in recognizable form, said reproduced data signals.
  • 80. A method of controlling the use of data signals, comprising the steps of:receiving and storing data signals; receiving and storing a first access control signal generated by a remote provider to grant a user rights to use said stored data signals; checking the stored first access control signal prior to decrypting the stored data signals to determine if said data signals are permitted to be used; receiving and storing a second access control signal generated by a remote provider to grant a user rights to use said stored data signals if said first access control signal does not grant said user rights to use said stored data signals, said second access control signal defining one or more of the number of times said stored data signals are permitted to be used and a temporal limit on which said stored data signals are permitted to be used; decrypting said stored data signals; and outputting said decrypted data signals.
  • 81. A method of controlling the reproduction of data signals, comprising the steps of:receiving and storing data signals in an encrypted form; receiving a request to reproduce said stored data signals; determining, in response to said received request, whether said stored data signals are permitted to be reproduced; connecting to a remote location to receive an access control signal generated by a remote provider to grant a user rights to reproduce said stored data signals if said request does not permit said stored data signals to be reproduced; decrypting said stored data signals; and reproducing said decrypted data signals.
  • 82. A method of controlling access to data signals, comprising the steps of:receiving a request from a user to use data signals; determining whether said user is a subscriber to use said data signals; determining if said request defines one or more of the number of times said data signals are permitted to be used and a temporal limit on which said data signals are permitted to be used; and transmitting to said user an access control signal determined by said request, if said user is determined to be a subscriber, said access control signal being generated by a remote provider to grant said user rights to use said data signals.
  • 83. The method of claim 82 wherein said step of transmitting said access control signal to said user includes the step of satisfying terms of payment for said use of said data signals.
  • 84. The method of claim 83 wherein said terms of payment are prepayment by said user for the use of said data signals.
  • 85. The method of claim 83 wherein said terms of payment are immediate payment by said user for the use of said data signals.
  • 86. A method of erasing stored data signals, comprising the steps of:storing an erase control signal which establishes a time on which said stored data signals are to be erased; receiving an access control signal generated by a remote provider to grant a user rights to use said stored data signals; and erasing said stored data signals at the time established by said erase control signal upon satisfying conditions of use of said stored data signals determined by said access control signal.
  • 87. A method of controlling the reproduction of data signals, comprising the steps of:receiving and storing data signals; receiving and storing a first access control signal generated by a remote provider to grant a user rights to reproduce a selected portion of said stored data signals; permitting reproduction of only said portion of said stored data signals, consistent with said first access control signal; transmitting a request to reproduce at least the remainder of said stored data signals; receiving a second access control signal generated by a remote provider in response to said request to grant a user rights to reproduce said stored data signals, said second access control signal defining one or more of the number of times said stored data signals are permitted to be reproduced and a temporal limit on which said stored data signals are permitted to be reproduced; and reproducing said stored data signals consistent with said second access control signal.
  • 88. A method for controlling access to data signals stored in an encrypted form, comprising the steps of:receiving via a signal transmission medium a first access control signal; receiving, subsequent to the reception of said first access control signal, a second access control signal, said first and second access control signals being generated by a remote provider to grant a user rights to access said stored data signals, and said second access control signal representing a temporal limit on which said stored data signals are permitted to be accessed; replacing said first access control signal with said subsequently received second access control signal prior to using said stored data signals; and decrypting said stored data signals if said second access control signal indicates that said stored data signals may be used.
Priority Claims (1)
Number Date Country Kind
6-180637 Jul 1994 JP
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Divisions (1)
Number Date Country
Parent 08/499332 Jul 1995 US
Child 09/641611 US
Reissues (1)
Number Date Country
Parent 08/499332 Jul 1995 US
Child 09/641611 US