Patent Publication Number: US-2006015889-A1

Title: Method of notifying a user of payment information for a pay program and a broadcast receiver for performing the same

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
      This application claims the benefit under 35 U.S.C. 119(a) of Korean Patent Application No. 10-2004-0051126 filed on Jul. 1, 2004 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.  
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a digital broadcast receiver. More particularly, the present invention relates to a method of notifying a user of payment information for a pay program, which is performed in a digital broadcast receiver.  
      2. Description of the Related Art  
      TV broadcasting is currently moving from an analog broadcasting system to a digital broadcasting system. In many countries, TV broadcasting has been digitalized since around 2000. The digitalization of TV broadcasting is expected to be completed by around 2010, and thus, afterwards, analog broadcasts will not be serviced any more while digital broadcasts are expected to have even wider use in the future.  
      In anticipation of a rapid increase in a wide variety of digital multimedia service programs, effective protection and management of digital multimedia service providers&#39; revenue and consumers&#39; rights have become a subject of great public attention and concern. In this regard, in order to effectively protect those rights, techniques for efficiently protecting and managing copyrights of multimedia content should be developed. Digital data, in particular, can be easily and quickly copied and can be unlimitedly transmitted and distributed. In addition, even copied digital data provides flexibility in editing and composition without degrading the quality of the original digital data.  
      Recent developments in satellite- or network-based data transmission technology would be a benefit to users because they can maximize a users&#39; convenience by efficiently providing a variety of multimedia services, such as music or video services, to users, but they would be an intimidation to service providers or copyright holders because they make it more difficult to stably provide multimedia content to users. This is especially true when considering that an increasing number of literary, musical, dramatic, or artistic works have been digitalized and digital data can be easily copied, edited, and distributed illegally using personal computers. Accordingly, a more vigorous research on the protection of copyrights of multimedia content is strongly required.  
      Digital broadcasting is characterized by providing multiple channels, high-quality broadcast programs, and multiple functions. The development of multiplexing technology has enabled video, audio, and other data to be transmitted together, regardless of their contents and sizes, and interactive services to be provided to many viewers through the formation of return channels based on modems. Accordingly, digital broadcasting can overcome restrictions of conventional analog broadcasting and can provide high value-added multimedia services to viewers. However, unless a desired level of security is established between a sender and a receiver of digital broadcasting, the current commercial base of digital broadcasting may collapse. Broadcasting businesses anticipate that they will be able to break from conventional ways of doing business, such as depending on advertisement revenues, and provide high-quality broadcasting services to their subscribers by increasing the number and variety of channels and that they will be able to collect subscription fees from the subscribers for high-quality pay programs according to either a pay-per-time method or a pay-per-view. In addition, broadcasting businesses also expect various multimedia data that they transmit to be received only by authorized subscribers. In order to solve all these problems, a conditional access system (CAS) has been developed.  
      Nowadays, a user of a set-top box is authenticated on a per-program basis by a CAS and is then allowed to watch a pay program only when successfully authenticated. In this manner, a per-program charging policy can be realized. Specifically, a user is entitled to watch a predetermined pay program or any pay programs for a predetermined amount of time if he or she pays an appropriate subscription fee. If the user&#39;s subscription right expires, the user is not able to watch pay programs unless he or she pays for them again. Accordingly, a system, such as a set-top box, should notify the user that his or her subscription right is about to expire and thus prevent the user from being discouraged from watching existing or new pay programs because of unwanted stoppage of broadcasting.  
      In this regard, a message indicating the user&#39;s payment information for a pay program has conventionally been displayed on a main screen  1  of a broadcast display device using an on-screen display  2 , as shown in  FIG. 1 , or displayed on a front panel  4  of a set-top box  3  using a light emitting diode (LED), as shown in  FIG. 2 .  
      However, in the case of the user notification method of  FIG. 1 , a user cannot be notified of whether his or her subscription right expires unless he or she turns on and then watches TV, and may be inconvenienced while watching TV due to the on-screen display  2  blocking part of the main screen  1 .  
      In addition, in the case of the user notification method of  FIG. 2 , the user is likely to overlook the front panel  4  because users tend to focus more on the screen of a TV than on the front panel  4  while watching a TV program.  
     SUMMARY OF THE INVENTION  
      The present invention provides a payment information notification method used in a digital broadcast receiver, which notifies a user of payment information on a pay program.  
      According to an aspect of the present invention, there is provided a broadcast receiver comprising a broadcast reception unit, which receives a broadcast signal of the pay program, a smart card, which comprises subscriber information, a conditional reception module, which compares authentication information included in the broadcast signal with the subscriber information and descrambles the broadcast signal if a user of the broadcast receiver is an authorized user, a valid information verification module, which extracts valid information from the descrambled broadcast signal, and an acoustic output unit, which notifies the user that the value of the extracted valid information is less than a predetermined critical value by using speech if the value of the extracted valid information is less than the predetermined critical value.  
      The valid information may be one of information on the amount of time left for the user to watch the pay program, and information on the number of times left for the user to watch the pay program.  
      The broadcast receiver may further comprise an audio and video (AV) reconstruction unit, which reconstructs original video and audio signals from the descrambled broadcast signal.  
      The acoustic output unit may comprise a voice source storage module, which stores a voice source segment corresponding to a predetermined text message and a default voice source, an acoustic composition module, which provides speech using the voice source segment and the default voice source if the value of the extracted valid information is less than the predetermined critical value, and a speaker, which outputs the speech to the user.  
      According to another aspect of the present invention, there is provided a method of notifying a user of payment information for a pay program. The method comprising receiving a broadcast signal of the pay program, comparing authentication information contained in the broadcast signal with subscriber information contained in a smart card and descrambling the broadcast signal if a user of the smart card is an authorized user, extracting valid information from the descrambled broadcast signal, and notifying the user that the value of the extracted valid information is less than a predetermined critical value by using speech if the value of the extracted valid information is less than the predetermined critical value.  
      The valid information may be one of information on the amount of time left for the user to watch the pay program, and information on the number of times left for the user to watch the pay program.  
      The notifying may comprise storing a voice source segment corresponding to a predetermined text message and a default voice source, providing speech using the voice source segment and the default voice source if the value of the extracted valid information is less than the predetermined critical value, and outputting the speech to the user.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The above and other features and advantages of the present invention will become more apparent by describing in detail preferred embodiments thereof with reference to the attached drawings in which:  
       FIG. 1  is a diagram illustrating a TV screen that displays a message indicating that the right to view a pay program will expire in one hour;  
       FIG. 2  is a diagram illustrating a front panel of a set-top box displaying a message indicating the right to view a pay program will expire in one hour;  
       FIG. 3  is a block diagram of a broadcast receiver according to an exemplary embodiment of the present invention; and  
       FIG. 4  is a flowchart of a method of notifying a user of payment information for a pay program according to an exemplary embodiment of the present invention. 
    
    
      Throughout the drawings, the same or similar elements are denoted by the same reference numerals.  
     DETAILED DESCRIPTION OF AN EXEMPLARY EMBODIMENT  
      The present invention will now be described more fully with reference to the accompanying drawings, in which an embodiment of the invention is shown. Advantages and features of the present invention and methods of accomplishing the same may be understood more readily by reference to the following detailed description of the embodiment and the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiment set forth herein. Rather, this embodiment is provided so that this disclosure will be thorough and complete and will fully convey an example of the concept of the invention to those skilled in the art.  
       FIG. 3  is a block diagram of a broadcast receiver  100  according to an exemplary embodiment of the present invention.  
      Referring to  FIG. 3 , the broadcast receiver  100  comprises a broadcast reception unit  30 , a conditional reception module  12 , an audio and video (AV) reconstruction unit  40 , a central processing unit  20 , a valid information verification unit  21 , a smart card reading module  22 , and an acoustic output unit  50 .  
      The broadcast receiver  100  will now be described as being applicable in receiving digital terrestrial, satellite, or cable broadcast programs. In addition, the broadcast receiver  100  may comprise a set-top box, a digital TV, and other digital broadcast receivers.  
      The broadcast reception unit  30  receives a broadcast signal  5 . The broadcast reception unit  30  comprises a tuner  10  and a demodulator  11 . The tuner  10  converts the broadcast signal  5  to have a middle frequency level, and provides the conversion result to the demodulator  11 . For example, the broadcast reception unit  30  receives a broadcast signal from a satellite, detects an I/Q signal from the received broadcast signal, and provides the detected I/Q signal to the demodulator  11 .  
      The demodulator  11  reconstructs a transport stream from the conversion result provided by the tuner  10  and provides the transport stream to the conditional reception module  12 . For example, the demodulator  11  may comprise a quadratic phase shift keying (QPSK) demodulator, which performs a QPSK demodulation operation, and a forward error correction (FEC) demodulator, which performs a FEC demodulation operation.  
      The conditional reception module  12  performs a user authentication operation using the transport module provided by the demodulator  11  using a smart card  6 . If the transport stream is successfully authenticated, the conditional reception module  12  descrambles the transport stream and then provides the descrambled transport stream to a demultiplexing module  13 . Otherwise, the conditional reception module  12  does not descramble the transport stream. The transport stream, which is scrambled, cannot be reproduced without being descrambled by the conditional reception module  12 . Scrambling is an operation of mixing multimedia data according to a predetermined rule so that an unauthorized user cannot view the multimedia data.  
      The user authentication operation performed by the conditional reception module  12  will now be described in detail. The smart card  6 , which is provided by a conditional access system (CAS) supplier, comprises subscriber information. The smart card  6  is a readable and writable memory unit that can be inserted into or detached from the broadcast receiver  100 . The subscriber information contained in the smart card  6  is read by the smart card reading module  22 , and the read subscriber information is provided to the conditional reception module  12 .  
      The conditional reception module  12  compares authentication information contained in the transport stream provided by the demodulator  11  with the subscriber information read from the smart card  6  by the smart card reading module  22  and performs a user authentication operation by determining whether a user of the broadcast receiver  100  is an authorized user based on the comparison results. An example of the authentication information may be an entitlement command message (ECM).  
      As a result, if the user is determined to be an authorized user, the conditional reception module  12  descrambles in real time the transport stream provided by the demodulator  11 . The descrambled transport stream is reconstructed by the demultiplexing module  13  and the AV decoding module  14  and then displayed.  
      The descrambled transport stream comprises an entitlement management message (EMM), which comprises valid information specifying the user&#39;s rights to a predetermined pay program. The valid information may be information on the amount of time left for the user to watch the predetermined pay program, i.e., the amount of remaining authorized viewing time, or information on the number of times left for the user to watch the predetermined pay program, i.e., the number of remaining authorized viewing times.  
      The valid information verification module  21  reads the EMM contained in the descrambled transport stream, extracts valid information from the EMM, and determines whether the value of the valid information is less than a predetermined critical value. If the determination results show that the value of the valid information is less than the predetermined critical value, the valid information verification module  21  transmits the valid information to an acoustic composition module  23  via the central processing unit  20 . For example, if the broadcast receiver  100  adopts a pay-per-time method and the valid information indicates that the amount of remaining authorized viewing time is not greater than a first critical value tc 1 , the valid information verification module  21  may notify the acoustic composition module  23  that the amount of remaining authorized viewing time is not greater than the first critical value tc 1 . On the other hand, if the broadcast receiver  100  adopts a pay-per-view method and the valid information indicates that the number of remaining authorized viewing times is not greater than a second critical value tc 2 , the valid information verification module  21  notifies the acoustic composition module  23  that the number of remaining authorized viewing times is not greater than the second critical value tc 2 . The first or second critical value tc 1  and tc 2  may be set in the broadcast receiver  100  in advance as a default value or may be set later by the user.  
      The central processing unit  20  issues a command to generate an audible signal such as a voice to the acoustic composition module  23 , and the acoustic composition module  23  composes a voice to be output to the user using voice sources stored in a voice source storage module  24  and then outputs the composed voice via a speaker  25 .  
      The acoustic output unit  50  may comprise the acoustic composition module  23 , the voice source storage module  24 , and the speaker  25 . The voice generated by the acoustic composition module  23  may be a beeping sound, and preferably, a composed voice message notifying the user of a current situation. Accordingly, the acoustic output unit  50  may output a composed voice to notify the user of the amount of remaining authorized viewing time or the number of remaining authorized viewing times. In order for the acoustic output unit  50  to output a composed voice, the voice source storage module  24  stores a voice source segment corresponding to a predetermined text message and provides the voice source segment to the acoustic composition module  23  if the acoustic composition module  23  requests the predetermined text message.  
      For example, assuming that the user&#39;s remaining authorized viewing time is 2 hours and the user is notified of the remaining authorized viewing time using a voice message, e.g., “your remaining authorized viewing time is 2 hours”. The acoustic composition module  23  stores a default voice source corresponding to “your remaining authorized viewing time is” and a voice source corresponding to a predetermined number of hours, such as ‘one hour’, ‘two hours’, or ‘three hours’. Thereafter, the voice source storage module  24  receives number information specifying the user&#39;s remaining authorized viewing time is 2 hours from the acoustic composition module  23  and returns the default voice source and the voice source corresponding to ‘two hours’ to the acoustic composition module  23 . The acoustic composition module  23  generates the voice message, e.g., “your remaining authorized viewing time is 2 hours”, by composing the default voice source and the voice source corresponding to ‘two hours’ received from the voice source storage module  24  and outputs the generated voice message to the user via the speaker  25 .  
      Referring to  FIG. 3 , the AV reconstruction unit  40  reconstructs original video and audio signals from the transport stream received from the conditional reception module  12 . The AV reconstruction unit  40  comprises the demultiplexing module  13 , the AV decoding module  14 , and an AV output module  15 .  
      The demultiplexing module  13  demultiplexes video and audio signals from the transport stream received from the conditional reception module  12  by parsing the corresponding transport stream under the control of the central processing unit  20  and then provides the video and audio signals to the AV decoding module  14 .  
      The AV decoding module  14  comprises a video decoder and an audio decoder and transmits the video and audio signals received from the demultiplexing module  13  to the AV output module. The AV decoding module  14  may be realized using various audio and video decompression methods and standards, such as Moving Picture Experts Group (MPEG)-2, MPEG-4, MPEG Layer-3 (MP3), and Audio Compression-3 (AC-3).  
      The AV output module  15  processes the video and audio signals transmitted from the AV decoding module  14  and provides the processed video and audio signals to external video and audio output devices. For example, the AV output module  15  may process the decoded video signal using a National Television Systems Committee (NTSC) encoder. Specifically, the AV output module  15  decodes the video signal and then outputs the decoded video signal to the external video output device. The AV output module  15  may use a phase alternation line (PAL) encoder, instead of the NTSC encoder, to decode the video signal. In addition, the AV output module  15  may decode the audio signal using an audio decoder and a digital-to-analog (D/A) converter and then output the decoded audio signal to the external audio output device.  
      The central processing unit  20  controls the operation of the entire broadcast receiver  100 . The central processing unit  20  may be installed in the conditional reception module  12 , the demultiplexing module  13 , or the AV decoding module  14  even though illustrated in  FIG. 3  as a unit separate from the conditional reception module  12 , the demultiplexing module  13 , or the AV decoding module  14 .  
      In  FIG. 3 , the term ‘module’, as used herein, means, but is not limited to, a software or hardware component, such as a Field Programmable Gate Array (FPGA) or Application Specific Integrated Circuit (ASIC), which performs certain tasks. A module may advantageously be configured to reside on the addressable storage medium and configured to execute on one or more processors. Thus, a module may comprise, by way of example, components, such as software components, object-oriented software components, class components and task components, processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. The functionality provided for in the components and modules may be combined into fewer components and modules or further separated into additional components and modules. In addition, the components and modules may be implemented such that they execute programs in one or more computers in a communication system.  
       FIG. 4  is a flowchart of a method of notifying a user of payment information for a pay program according to an exemplary embodiment of the present invention.  
      Referring to  FIGS. 3 and 4 , in operation S 1 , a broadcast signal received from a broadcast signal sender by the tuner  10  is converted to have a middle frequency level. The converted broadcast signal is demodulated by the demodulator  11 , thereby reconstructing a transport stream. In operation S 2 , the transport stream is provided to the conditional reception module  12 .  
      In operation S 3 , it is determined whether a user of the broadcast receiver  100  needs to be authenticated. If the user of the broadcast receiver  100  does not need to be authenticated in operation S 3 , the conditional reception module  12  bypasses the transport stream. Thereafter, in operation S 12 , the bypassed transport stream is demultiplexed and then decoded, thereby obtaining an audio or video signal. If the user of the broadcast receiver  100  needs to be authenticated, the conditional reception module  12  reads subscriber information contained in the smart card  6  inserted into the broadcast receiver  100  with the aid of the smart card reading module  22  in operation S 4 .  
      Thereafter, the conditional reception module  12  determines whether the user of the broadcast receiver  100  is an authorized user based on a result of comparing authentication information contained in the transport stream with the subscriber information read from the smart card  6  by the smart card reading module  22 . If the user of the broadcast receiver  100  is successfully authenticated in operation S 5 , the transport stream is descrambled in operation S 6 . In operation S 7 , the valid information verification module  21  reads an EMM from the descrambled transport stream.  
      In operation S 8 , the valid information verification module  21  extracts valid information from the EMM and determines whether the value of the valid information is less than a predetermined critical value. If the determination results show that the value of the valid information is less than the predetermined critical value, the valid information verification unit  21  notifies the acoustic composition module  20  of the determination results via the central processing unit  20 .  
      For example, if the broadcast receiver  100  adopts a pay-per-time method and the valid information indicates that the amount of remaining authorized viewing time is not greater than a first critical value tc 1 , the valid information verification module  21  notifies the acoustic composition module  23  that the amount of remaining authorized viewing time is not greater than the first critical value tc 1 . Alternatively, if the broadcast receiver  100  adopts a pay-per-view method and the valid information indicates that the number of remaining authorized viewing times is not greater than a second critical value tc 2 , the valid information verification module  21  notifies the acoustic composition module  23  that the number of remaining authorized viewing times is not greater than the second critical value tc 2 .  
      The acoustic composition module  23  may notify the user of the amount of remaining authorized viewing time or the number of remaining authorized viewing times using a beeping sound, and preferably, a composed voice. The voice source storage module  24  stores a voice source segment corresponding to a predetermined text message and provides the voice source segment to the acoustic composition module  23  if the acoustic composition module  23  requests the predetermined text message.  
      In operation S 9 , the acoustic composition module  23  references the voice source segment, if any, provided by the voice source storage module  24  generates a voice to be output to the user based on the voice source segment in operation S 10 , and outputs the generated voice to the user via the speaker  25  in operation S 11 .  
      In operation S 12 , an audio or video signal is obtained by demultiplexing and then decoding the transport stream descrambled in operation S 6  and then is output.  
      In concluding the detailed description, those skilled in the art will appreciate that many variations and modifications can be made to the embodiments without substantially departing from the principles of the present invention. Therefore, the disclosed embodiments of the invention are used in a generic and descriptive sense only and not for purposes of limitation.  
      According to the embodiments of the present invention, it is possible to minimize a user&#39;s inconvenience caused by non-payment of a subscription fee for a pay program.  
      In addition, it is possible to efficiently and effectively notify the user of payment information.