Abstract:
There is provided, according to the present invention, a reproducing device capable of preventing illegal duplication and reproduction, as well as of reproducing content without degrading the quality of the audio and visual contents. 
     The reproducing device ( 100 ) comprises a first storage area ( 110 ), in which data is stored, using file system which is not supported by operating system of the reproducing device, an interface part ( 120 ) supporting the file system which the first storage area uses, accepting only reproducing request, reading out and supplying the data stored in the first storage area, wherein the reading out and supplying operations are hidden, and a reproducing part ( 132 ) reproducing the data supplied by the interface part.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a reproducing device, a reproducing method and a program used in the device and method, particularly relates to a reproducing device, a reproduction method and a program for reproducing audio and visual contents by network distribution. 
     2. Description of Related Art 
     Digital sound source and moving picture have replaced analog ones and digital audio-visual system, sound source content, visual content, media and the like have been available as well. However, since digital content is easily duplicated, various techniques have been provided for copyright protection of the content. 
     As prior art to realize the download processing suitable for copyright-protected data, an information processing device and its method are disclosed, in which a privileged space is set in an information processing space, and a download program and a recording medium interface program are allowed to operate in the privileged space. Then, download data whose copyright protection is necessary are recorded in an external storage medium by processing in the privileged space so that it is possible to prevent any direct access to the external recording medium from a user program or the like arranged in an unprivileged space (see JP2002-7194). 
     SUMMARY OF THE INVENTION 
     As mentioned above, various techniques have been proposed for copyright protection of content. However, those techniques achieve duplication prevention and encryption by processing audio and visual contents, which results in degradation of the quality of audio and visual contents. In addition, in the current music distribution systems, sound source content is often lossy compressed in order to reduce the network load in distributing the sound source content. Therefore, much more attention has been paid to prevention of duplication and encryption method for copyright protection and reduction of network load than sound quality. 
     It is, therefore, an object of the present invention to provide a reproducing device capable of preventing illegal duplication and reproduction, as well as of reproducing content without degrading the quality of the audio and visual contents. 
     A reproducing device according to the first invention comprises 
     a first storage area, in which data is stored, using file system which is not supported by operating system of the reproducing device, 
     an interface part supporting both of the file system which the first storage area uses and file system supported by the operating system of the reproducing device, including
         a user interface part accessible from outside of the reproducing device, and   an acquiring and reproducing interface part(s) accepting only reproducing request for reproducing the data stored in the first storage area, supplied through the user interface part, reading out and supplying the data stored in the first storage area, wherein the reading out and supplying operations are hidden, and       

     a reproducing part for reproducing the data supplied through the interface part, using the file system supported by the operating system of the reproducing device. 
     In the reproducing device according to the second invention, 
     the reproducing request is a stream-reproducing request, 
     the interface part reads out the data stored in the first storage area and supplies the date to the reproducing part in a stream-reproducing form, and 
     the reproducing part is configured as a stream-reproducing part for stream-reproducing the data supplied to in the stream-reproducing form. 
     In the reproducing device according to the third invention, 
     the interface part further comprises a monitoring part for judging whether the operating system of the reproducing device is secure or not, 
     when the monitoring part judges that the operating system is secure, the acquiring and reproducing interface part reads out the data stored in the first storage area and supplies the data to the reproducing part, 
     when the monitoring part judges that the operating system is not secure, the interface part changes the operating system in a secure state, afterward, the acquiring and reproducing interface part reads out the data stored in the first storage area and supplies the data to the reproducing part, 
     the interface part controls the operating system kept in the secure state, and 
     the reproducing part reproduces the supplied data. 
     In the reproducing device according to the forth invention, 
     the reproducing device further comprises a second storage area used by the reproducing part, 
     the interface part further comprises a monitoring part for judging whether the second storage area is a secure storage area (a storage area kept in secret) or not, 
     when the monitoring part judges that the second storage area is a secure storage area, the acquiring and reproducing interface part reads out the data stored in the first storage area and supplies the data to the second storage area, 
     when the monitoring part judges that the second storage area is not a secure storage area, the interface part changes the second storage area in a secure state, afterward, the acquiring and reproducing interface part reads out the data stored in the first storage area and supplies the data to the second storage area, 
     the interface part keeps the second storage area in the secure state, and controls the second storage area so that the data supplied to the second storage area is stored, and 
     the reproducing part reproducing the data stored in the second storage area. 
     In the reproducing device according to the fifth invention, 
     the data stored in the first storage area, readout operation of the data and supplying operation of the data are hidden by encapsulation. 
     In the reproducing device according to the sixth invention, 
     the data stored in the first storage area is encoded, and the acquiring and reproducing interface part decodes the encoded data. 
     In the reproducing device according to the seventh invention, 
     the interface part comprises an initializing part having a formatting capability to format the first storage area in a file system which is not supported by the operating system of the reproducing device. 
     The reproducing device according to the eighth invention, further comprises 
     a communication part
         accepting only an acquiring request for acquiring new data,   acquiring new data from an external data supply device (via networks such as the Internet, a CD/DVD drive and a sound card), and   storing the acquired new data in the first storage area, in which the storing operation is hidden.       

     In the reproducing device according to the ninth invention, 
     the acquired new data and the storing operation are hidden by encapsulation. 
     In the reproducing device according to the tenth invention, 
     the second storage area is an auxiliary storage device. As an auxiliary storage device are listed what is connected to an external port such as a USB memory or what is connected via network. 
     A method for reproducing a reproducing device according to the eleventh invention comprises 
     a step of storing data in a first storage area using a file system which is not supported by operating system of the reproducing device, 
     a step of reading out and supplying the data stored in the first storage area by using an acquiring and reproducing interface part accepting only reproducing request for reproducing the data stored in the first storage area, supplied from outside of the reproducing device, in an interface part supporting both of the file system which the first storage area uses and file system supported by the operating system of the reproducing device, wherein the reading out and supplying operations are hidden by using computing means (a processor such as a CPU), and 
     a step of reproducing data supplied by the acquiring and reproducing interface part by using computing means (a processor such as a CPU). 
     A program for a computer to perform a reproducing method according to the twelfth invention, the program comprises 
     a step of storing data in a first storage area using a file system which is not supported by operating system of the reproducing device by using computing means (a processor such as a CPU), 
     a step of reading out and supplying the data stored in the first storage area by using an acquiring and reproducing interface part accepting only reproducing request for reproducing the data stored in the first storage area, supplied from outside of the reproducing device, in an interface part supporting both of the file system which the first storage area uses and file system supported by the operating system of the reproducing device, wherein the reading out and supplying operations are hidden by using computing means (a processor such as a CPU), and 
     a step of reproducing data supplied by the acquiring and reproducing interface part. 
     According to the present invention, it is possible to provide a reproducing device capable of realizing robust copyright protection by preventing illegal duplication and reproduction, as well as of reproducing high-quality audio and visual contents because no process is required such as compression of content accompanied with quality degradation of content. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an overall view of the reproducing device of the present invention, 
         FIG. 2  is a block diagram of the reproducing device according to an embodiment of the present invention, 
         FIG. 3  is a block diagram of the reproducing device according to another embodiment of the present invention, showing a signal and data flow disclosing reproduction data to the second storage area  130 , 
         FIG. 4  is a block diagram of the reproducing device according to another embodiment of the present invention, 
         FIG. 5  is a block diagram of the reproducing device according to another embodiment of the present invention, 
         FIG. 6  is a block diagram of the reproducing device according to another embodiment of the present invention, 
         FIG. 7  is a flow chart of reproducing process of the interface part of the reproducing device of the present invention, 
         FIG. 8  is a flow chart of controlling process of the interface part of the reproducing device of the present invention, and 
         FIG. 9  is a flow chart of data acquiring process of the interface part of the reproducing device of the present invention. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, the embodiments of the present invention will be described in detail with reference to the drawings.  FIG. 1  is an overall view of the reproducing device  100  of the present invention. The reproducing device  100  has a first storage area  110 , an interface part  120 , a second storage area  130  and an input connector part  140 . Data “A”, data “B”, data “C” and the like are stored in the first storage area  110 . The interface part  120  has a user interface part  122 , an initializing part  124 , an acquiring interface part  125 , a reproducing interface part  126 , a monitoring part  127  and a communication part  128 . The second storage area  130  has a reproducing part  132 , which reproduces data “A” stored in the second storage area  130  or the data stored in the first storage area  110 . The input connector part  140  has an analog input connector  142  and a digital input connector  144 . 
     The data supplied to the reproducing device  100  is obtained by being downloaded from a server  200  via the Internet NET. Alternatively, the data supplied to the reproducing device  100  may be analog content supplied from an analog reproducing device  210  (for example, a record player), or digital content supplied from a digital reproducing device  220  (for example, a CD player, a DVD player and a sound card). The data obtained from the external data supply device is acquired by the user interface part  122  with being controlled by the communication part  128 , and stored in the first storage area  110 , the second storage area  130  or other area (not shown) in the reproducing device. The second storage area  130  uses the file system, which is supported by the operating system of the reproducing device  100 , while the first storage area  110  uses the file system, which is not supported by the operating system so that the first storage area  110  cannot be accessed by a user. The interface part  120 , which connects the first storage area  110  and the second storage area  130 , supports the file system of the first storage area  110 . The interface part  120  can be accessed from the second storage area  130  only through the user interface part  122  and therefore, process in the interface part  120  is hidden from the outside. 
       FIG. 2  is a block diagram of the reproducing device  100  according to an embodiment of the present invention. The User interface part  122  has an input port  122   i  and an output port  122   o , through the input port  122   i , a reproducing request R 1  from a user is accepted and the requested data is supplied through the output port  122   o  to the reproducing part  132 . A reproducing request signal S 1  passes through the input port  122   i  of the user interface part  122  and it is converted into a reading request signal S 2  in a reproducing interface part  126 . The reading request signal S 2  is transmitted to the storage area  110 , data (for example, data “B” in  FIG. 2 ) in response to this reading request signal S 2  is transferred to the reproducing interface part  126 , and then transferred through the output port  122   o  of the user interface part  122  to the reproducing part  132  of the second storage area  130 . The reproducing part  132  reproduces thus-transferred data “B”. In the interface part  120 , converting, reading, transferring and supplying operations are hidden from a user, and therefore, a user can access the interface part  120  only through the user interface part  122 . 
     In a preferred embodiment of the present invention, the reproducing request R 1  from a user shown in  FIG. 2  is a stream-reproducing request, readout data is supplied in a streaming reproduction form and the reproducing part  132  is a stream-reproducing part for streaming reproduction. 
     Storing data in the first storage area  110  has advantage as follows, in comparison to the case of storing data created with robust protection/coding processing in the second storage area  130 . Firstly, the second storage area  130  uses the file system supported by the operating system (OS) of the reproducing device  100  and since a user-friendly environment (for example, Windows™) is preferable, plenty of information and analysis tools are available, and therefore its encryption function is very likely to be broken. Secondly, a hard disk, of which data is stored in the second storage area  130 , is physically detached, and attached to other devices having the same file system, or only the OS region of the second storage area  130  is re-installed so that the data can be duplicated. On the other hand, since the first storage area  110  uses the file system, which is not supported by the operating system of the reproducing device  100 , the first storage area  110  is unlikely to be accessed. In addition, general users cannot recognize a storage area in itself that the OS of a device in use does not support and they cannot recognize even more data stored therein. Therefore, music data stored in the first storage area  110  of the reproducing device  100  is kept in a secure state, in short, hidden from general users even though it is not encrypted. Thus, according to the present invention, it is possible to store unencrypted sound source data in the first storage area  110  while keeping its secrecy. In addition, even if the first storage area  110  is physically detached and attached to other devices, it is extremely difficult for general users to access data stored in the first storage area  110  because the first storage area  110  does not support general OS. In addition, if the first storage area  110  is formatted using the special file system which is not supported by UNIX™ or the like, the secrecy of the first storage area  110  improves more. As a result, as long as any special tools are used, without the device of the present invention, it becomes virtually impossible to access the first storage area  110  and data stored therein 
       FIG. 3  is a block diagram of the reproducing device according to another embodiment of the present invention, showing a signal and data flow disclosing reproduction data to the second storage area  130 . A reproducing request signal S 11  from a user is supplied through the input port  122   i  of the user interface part  122  to the reproducing interface part  126 . A data disclosure authorizing request signal S 12  is transmitted from the reproducing interface part  126  to the user interface part  122 . A second storage area security status confirming request signal S 13  is transmitted from the user interface part  122  to the monitoring part  127 . A second storage area security status acquiring request signal S 14  is transmitted from the monitoring part  127 , through the output port  122   o  to the second storage area  130 . A second storage area security status signal S 15  is transmitted through the input port  122   i  to the monitoring part  127 . A reproduction authorization signal S 16  is transmitted from the monitoring part  127  to the user interface part  122 . A reproducing request signal S 17  is transmitted from the user interface part  122  to the reproducing interface part  126 . A reading request signal S 18  is transmitted from the reproducing interface part  126  to the first storage area  110 . The data (for example, data “A” in  FIG. 3 ) in response to this reading request signal S 18  is transferred to the reproducing interface part  126 , passes through the output port  122   o  of the user interface part  122  and then is stored in the second storage area  130 . The stored data “A” is reproduced in the reproducing part  132 . In the example of  FIG. 3 , security status of the second storage area kept secure, however, when the second storage area  130  is not kept secure, the second storage area  130  is controlled, if necessary and changed in the secure state. 
       FIG. 4  is a block diagram of the reproducing device  100  according to another embodiment of the present invention, showing encryption and decryption in data acquisition and reproduction. In  FIG. 4 , solid arrows show unencrypted data and dotted arrows show encrypted data. The data is supplied through the input port  122   i  of the user interface part  122  to the acquiring interface part  125  and stored in the first storage area  110  in its original form or in an encrypted/decrypted form. Next, the stored data in its original form or after encrypted/decrypted in the reproducing interface part  126  is output from the output port  122   o  of the user interface region  122 . 
     The following cases are considered as a data acquiring method. 
     Case 1: When encryption is unnecessary in a recording operation, for example, unencrypted data is stored in the first storage area  110  in its original form. 
     Case 2: The acquired data, which is encrypted, is stored in the first storage area  110  in its original form, i.e. in the encrypted form. 
     Case 3: The acquired data, which is encrypted, is decrypted in the decrypting part  125 D of the acquiring interface part  125  and stored in the first storage area  110 . 
     Case 4: When encryption is necessary in a recording operation, unencrypted data is encrypted in the encrypting part  125 E of the acquiring interface part  125  and stored in the first storage area  110 . 
     In addition, the following cases are considered as a data reproducing method. 
     Case 5: The unencrypted data is supplied through the reproducing interface part  126  in it original form and output from the output port  122   o  of the user interface part  122 . 
     Case 6: When the stored data, which is encrypted, is decrypted by reproducing software, the encrypted data is just supplied from the output port  122   o  of the user interface part  122 . 
     Case 7: The stored data, which is encrypted, is decrypted in the decrypting part  126 D of the reproducing interface part  126  and supplied from the output port  122   o  of the user interface part  122 . 
     Case 8: When the data is encrypted at the time of data reading in a backup operation, the unencrypted data is encrypted in the encrypting part  126 E of the reproducing interface part  126  and supplied from the output port  122   o  of the user interface part  122 . 
       FIG. 5  is a block diagram of the reproducing device  100  according to another embodiment of the present invention, showing the initialization of the second storage area  130 . In the interface part  120 , the input port  122   i  accepts operating instructions and the user interface part  122  creates physics partition (process P 1   a , P 1   b ), assuming that the first storage area  110  supports UNIX™ system OS. Next, the user interface part  122  creates and initializes the file system, which is not supported by the operating system of the reproducing device  100  (process P 2   a , P 2   b ). Next, a storage area of data, such as databases are created and initialized (process P 3   a , P 3   b ). When the above-mentioned processed are completed, status indication is output from the output port  122   o.    
       FIG. 6  is a block diagram of the reproducing device  100  according to another embodiment of the present invention, showing a flow that content is downloaded from a server to be stored in the first storage area  130 . A data acquiring request signal S 21  from a user is supplied through the input port  122   i  of the user interface part  122  to the acquiring interface part  125 . A data acquiring request signal S 22  is supplied from the acquiring interface part  125  to the user interface part  122 . A data acquiring request signal S 23  is supplied from the user interface part  122  to the communication part  128 . A data acquiring request signal S 24  is transmitted from the communication part  128  through the output port  122   o  of the user interface part  122  to a server  200 , which is an external device via the Internet NET. An acquired data signal S 25  is transmitted from the server  200  through the input port  122   i  of the user interface part  122  and the acquiring interface part  125  to be stored in the first storage area  110  (data “C” in  FIG. 6 ). 
       FIG. 7  is a flow chart of reproducing process of the interface part of the reproducing device of the present invention. In step St 1 , a reproducing request from a user is accepted in the interface part. In step St 2 , the reproducing request from the interface part is received in the monitoring part, which monitors secrecy of the second storage area. In step St 3 , it is judged whether the second storage area is kept in secret. If yes in step St 3 , in step St 4 , data stored in the first storage area is disclosed and supplied to the reproducing part by the interface part. In step St 5 , a termination request is accepted. In step St 6 , it is judged in the interface part judges whether there is a termination request and the interface part keeps waiting for a termination request. When a termination request is received in the interface part, in step St 7 , a termination process proceeds. 
     In step St 3 , if it is judged that the second storage area is not kept in secret, in step St 8 , the second storage area is changed to a secure state. In step St 9 , secrecy of the second storage area is judged and when it is judged that the second storage area is kept in secret, the process moves to step St 3  and otherwise to step St 7 . 
       FIG. 8  is a flow chart of controlling process of the interface part of the reproducing device of the present invention. In step St 11 , the interface part accepts a reproducing request from a user. In step St 12 , the monitoring part, which receives the reproducing request from the interface part, monitors the secrecy of the operating system. The monitoring part monitors, for example, (1) authority of a logon user is normal, (2) folder or file access permission of a hard disk area in the operating system is kept secure, (3) no unnecessary devices are connected, (4) no unnecessary applications and services are running, and (5) system setting such as policy registry is kept normal. In step St 13 , if it is confirmed that the operating system is kept secure, in step St 14 , data stored in the first storage area is disclosed and supplied to the reproducing part by the interface part. 
     In step St 13 , it is judged whether the operating system is kept in secret of not. When the operating system is not kept in secret, in step St 15 , it is judged whether the operating system is controllable. If the operating system is controllable, in step St 16 , the state of the operating system is changed in a secure state. The changes are, for example, (1) change of the authority of a logon user, (2) change of the folder or file access permission of a hard disk area in the operating system, (3) stop or invalidation of any unnecessary devices, (4) stop of any unnecessary applications and services, and (5) change of the system setting such as policy registry. In step St 17 , it is judged whether the state of the operating system could be changed in a secure state, and if yes, the process returns step St 13  and if no, this control process is finished. In step St 15 , this control process is also finished when the operating system is not controllable. 
       FIG. 9  is a flow chart of data acquiring process of the interface part of the reproducing device of the present invention. In step St 21 , the interface part accepts an acquiring request from a user. In step St 22 , the interface part is connected to an external data supply device. The external data supply device is for example, a server via networks such as the Internet, a CD/DVD drive and a sound card. In step St 23 , it is judged whether the interface part could be connected to an external data supply device. If yes, in step St 24 , the interface part acquires data from the external data supply device and the acquired data is stored in the first storage area. In step St 25 , it is judged whether the acquisition of data is finished. If yes, in step St 28 , termination process proceeds and this data acquiring process is finished. If no in step St 25 , in step St 27 , a termination request is accepted. In step St 28 , it is judged whether there is a termination request or not and if yes, the process moves to the termination process of step St 26 . In step St 28 , if there is no termination request, the process returns step St 24  and the data acquiring process is continued.