JP2007294054A - Digital image recording / playback device - Google Patents

Abstract

Content such as video data that has been recorded when a defect matches a recording medium such as an HDD is lost, and there is a limitation in recording content on an external recording medium. was there.
When a content is backed up from one recording medium to another with a plurality of recording media, a list of the backed up content is held, and a list of the backed up content is recorded when the recording medium is defective The content is restored while using it. In addition, by performing encryption based on information for distinguishing recording media, restrictions on content recording are improved.
[Selection] Figure 1

Description

  The present invention relates to a content backup in an apparatus for recording / reproducing contents such as digital video, audio, and electronic information on a recording medium through digital broadcasting, and a management method thereof.

  There are the following conventional examples relating to a recording / reproducing apparatus for storing contents such as digital broadcasting. In recent years, digital broadcasting has started, and devices for recording digital broadcast signals as bit streams have been commercialized. In general, an MPEG transport stream (hereinafter abbreviated as MPEG-TS) is adopted for digital broadcasting.

  This will be described with reference to FIG. In digital broadcasting, in order to enable conditional access (limited reception), MPEG-TS is encrypted and a modulated signal is sent. On the receiver side, the signal received by the antenna 01 is demodulated by the tuner 04 and a signal of a necessary channel is extracted. The extracted signal is authenticated using a B-CAS card for authentication means for realizing conditional access, for example, digital broadcasting in Japan, and key information for decryption is extracted. Decryption is performed by the descrambler 05 based on this key information, and MPEG-TS is generated.

  In this MPEG-TS, a plurality of program streams are multiplexed. In order to extract a stream required by the user, the TS-DEMUX 11 divides the stream, and only a necessary part is extracted ( Partial TS) is taken out. For display, the partial TS is divided into section information indicating program information and electronic data such as a VIDEO stream, an AUDIO stream, and data broadcasting. Thereafter, the VIDEO stream is subjected to video decoding processing by the VIDEO decoder 07 and output to the display device 08 for viewing together with information such as data broadcasting. The AUDIO stream is audio-decoded by the AUDIO decoder 12 and output to the speaker 13.

  On the other hand, devices that record digital broadcast video as digital content, such as VIDEO streams, AUDIO streams, and electronic data such as data broadcasts, as digital content, instead of conventional analog recording, have been commercialized. This will be described with reference to FIG. Examples of storage media include magnetic tape, HDD (Hard Disk Drive), DVD (Digital Versatile Disc), and memory.

  When recording a digital stream, since there is no deterioration due to recording unlike conventional analog recording, copyright management for protecting the copyright becomes important. For copyright management of digital broadcasting, specify copy conditions as copy control information (CCI: Copy Control Information) for each content, and specify "Copy prohibited", "Copy once", or "Copy allowed" For example, limiting replication. The copy control information of the content that can be recorded on the recording medium is in the state of “Copy once” and “Copy permitted”, and cannot be recorded in the state of “Copy prohibited”. In addition, content that is in the state of “copyable once” becomes “copy prohibited” when it is recorded on the storage medium, and so-called grandchild copy is not possible. Copying can be performed multiple times, as well as those in the “copying enabled” state.

  Content that has become “copy prohibited” due to recording from a “copy once” status is prohibited from being copied next, but is generally permitted to move to other storage media (hereinafter “move”). ing. In recent years, contents of digital broadcasting have become “mainly copyable once” as copy control information (hereinafter referred to as “copy once”), and copy management has become important. In addition to the copy management, it is necessary to prevent the content recorded on the recording medium from being illegally copied by other means.

  Standards such as D-VHS, which uses magnetic tape as a recording medium as a device for recording digital broadcasts, have been determined and commercialized. By recording and storing the received digital broadcast on a magnetic tape, the magnetic tape can be taken out and reproduced on other devices. The DTCP (Digital Transmission Content Protection) specification has been established from an early stage as a copy protection technique required when contents are exchanged using the IEEE1394 I / F09 as a connection means between the devices. This DTCP performs authentication between devices, performs encryption by the encryption circuit 10 according to the agreement, and transfers the stream. Also, it discriminates CCI and performs copy management. When the previous copy-once content is moved via IEEE 1394, the original content is surely erased between the devices according to the DTCP standard, and copy management is guaranteed.

  On the other hand, when a DVD is used as a recording medium, a CPRM (Content Protection for Recordable Media) compatible disc is used for copyright management. This has a unique number for each disc, and by using this as a key for encryption in the encryption circuit 15, the content and the disc can be associated one-to-one. Even if data is copied to another medium, the unique number for each disc is different, so that the encryption cannot be normally decrypted. Therefore, even if the previous copy-once content is recorded, copy management is performed correctly.

  Some DVDs do not support CPRM but cannot be used for recording copy-managed content. Conventionally, DVD media compatible with CPRM are mainly rewritable, but CPRM compatible DVD media have been commercialized. In a device that uses an HDD as a recording medium, the same HDD as that used in a PC (personal computer) is used in terms of performance and cost.

  A stream sent by digital broadcasting is authenticated by a B-CAS card, and descrambled by a descrambler 05. The decrypted stream is subjected to local encryption by the encryption circuit 14 using a device-specific key before recording in the HDD, and recorded in a unique format. This prevents the HDD from being taken out and illegally copied or altered by another PC or the like.

  As a recent product trend, there are many products that integrate HDD and DVD, and the main usage is to first record digital broadcasts on the HDD, and delete unnecessary contents that were viewed and deleted. Since the capacity of the HDD is limited, the content is copied to the DVD or moved and left.

  The HDD is built-in and cannot exchange with other devices, but can be played back on other devices by recording content on a DVD. FIG. 6 shows an example of this. The boxes shown in STEP 1 to STEP 3 in the figure are data images of the disk media inserted in the built-in DVD and data blocks of the built-in HDD which are simply imaged for the purpose of explanation where there are many data blocks.

  In STEP 1, there is no content in the built-in DVD medium, and the format before recording is completed. A part of the data block is used for the file management information, and the rest is free. Generally, the file management information is not encrypted. Content 1 and content 2 have been recorded in the built-in HDD. Part of the data block is used for File management information. Generally, the file management information is not encrypted. In some cases, it is used to manage content information. Generally, content management information is encrypted and recorded using a device-specific key (hereinafter referred to as “Deck_Key”). The content is also encrypted and recorded using Dec_Key.

  STEP2 represents a state in which the content 3 is newly recorded. Content 3 is encrypted with Deck_Key and recorded in the data block. At the same time, the content management information reflecting the addition of the content 3 is encrypted and updated using the Dec_Key. Subsequently, the file management information is recorded reflecting the added state of the content 3 and the updated state of the content management information.

  STEP 3 represents a state in which the content 2 is moved from the internal HDD to the internal DVD medium. After the content 2 is decrypted with the Deck_Key, it is encrypted according to a standard such as CPRM for recording on the DVD, recorded on the medium, and the file management information is updated. After the recording on the DVD is confirmed, the content management information and the file management information are updated in order to delete the content 2 from the internal HDD.

Recently, models that perform recording and reproduction with an external HDD have come out. As a connection method, there are a connection using a LAN I / F 16 and a connection using a USB I / F 16.
In this case, the recording format can be read by a PC, but the content to be recorded is subjected to local encryption using the encryption circuit 14 so that it can be reproduced only by the recording device. Although it can be connected to other devices, moved, copied, etc. for external attachment, copyright protection is performed by limiting the devices that can be played. However, since copying can be performed freely, even if an attempt is made to move to a DVD, since there are a plurality of original contents, it is not possible to delete all of them, so that the move cannot be performed.

  As shown in FIG. 7, STEP1 and STEP2 are the same as those described in FIG. 6 above, but the DVD move from the HDD of STEP3 is prohibited. As shown in STEP3-NG and STEP4-NG, this causes a problem when the move is permitted. For example, in the state of STEP2, the contents of the external HDD are stored and held in another HDD. Then, after the content 2 is moved as in STEP3-NG, the content 2 is originally lost in the external HDD, but it can be returned to the state in STEP2 that was held as in STEP4-NG. In this case, the content 2 exists in both the DVD and the HDD, and the copy management fails.

On the other hand, there is a conventional technique as a method for protecting management information. According to Japanese Patent Laid-Open No. 2004-228561, there is described a technique for preventing copying of content stored in a recording medium by providing management information in an EEPROM or the like separately from the recording medium on which the content is recorded.
JP 2003-167686 A

  However, in the case of the built-in HDD type in the conventional HDD recording / reproducing apparatus as described above, there is a problem that content such as video data recorded when a defect occurs in the built-in HDD is lost. is doing.

On the other hand, in the case of the external HDD type, the content can be duplicated, so that if one HDD is defective, the content can be restored, but it cannot be moved to other media during normal use. Have the problem of being restricted.
In addition, when taking a method in which management information is provided separately from the recording medium in order to prevent duplication, it is necessary to use an enormous storage element for storing the management information, which causes a problem of an increase in cost. is doing.

  The present invention has been made in view of such a situation. When creating a backup of content, only the list is left in the holding unit, and content can be restored in the event of an HDD failure while reducing costs. An object of the present invention is to provide a method that enables safe movement to other media during normal use.

The present invention provides means for solving these problems, and the present invention constitutes the following technical means.
In order to achieve the above object, a digital image recording / reproducing apparatus according to a first aspect of the invention is a recording / reproducing apparatus for recording a content such as video data on a recording medium, and reading the recorded content from the recording medium and reproducing it. B) means for generating information for distinguishing each device; c) means for performing encryption based on the information distinguished for each device when recording content; and d) performing encryption. Means for recording the recorded content on the recording medium, e) means for backing up the content from one recording medium to the other with a plurality of recording media, and f) means for holding a list of the backed up content G) means for restoring contents while judging using a list of contents that were backed up when the recording medium is replaced due to a defect. To.

  A digital image recording / reproducing apparatus according to a second aspect of the invention is a recording / reproducing apparatus that records a content such as video data on a recording medium, reads out the recorded content from the recording medium, and reproduces it. B) For each device Means for generating information for distinguishing, c) means for generating information for distinguishing each recording medium to be recorded, and d) information and contents for distinguishing each device when recording the contents And a means for performing encryption based on information for distinguishing the recording medium to be recorded, and e) means for recording the encrypted content on the recording medium.

  A digital image recording / reproducing apparatus according to a third aspect of the invention is a recording / reproducing apparatus that records a content such as video data on a recording medium, reads out the recorded content from the recording medium, and reproduces it. B) For each device Means for generating information for distinguishing, c) means for generating information for distinguishing each recording medium to be recorded, and d) information and contents for distinguishing each device when recording the contents Means for performing encryption based on information for distinguishing the recording medium to be recorded; e) means for recording the encrypted content on the recording medium; and f) having a plurality of recording media from one recording medium. Means for backing up content to the other side, g) means for holding a list of backed up contents, and h) a controller that backed up when the recording medium was replaced due to a defect. Characterized by comprising a means for performing the restore content while determining using a list of Ntsu.

  A digital image recording / reproducing apparatus according to a fourth aspect of the present invention is the digital image recording / reproducing apparatus according to any one of claims 1 and 3, wherein a non-volatile memory is provided as means for holding a list of contents that have been backed up. It is characterized by using.

  A digital image recording / reproducing apparatus according to a fifth aspect of the present invention is the digital image recording / reproducing apparatus according to any one of claims 1 to 4, wherein the recording medium is an HDD.

According to the present invention, the following effects are brought about.
Since the digital image recording / reproducing apparatus of the first invention is configured as described above, the recording medium can be backed up, and even when the recording medium becomes defective and cannot be used, an alternative recording medium can be used. The content can be restored from the backup data.

  Since the digital image recording / playback apparatus according to the second aspect of the present invention has the above-described configuration, it is possible to eliminate restrictions on moving content even when a plurality of recording media are used.

  Since the digital image recording / reproducing apparatus of the third invention has the above-described configuration, it is possible to back up the recording medium, and even when the recording medium becomes defective and cannot be used, an alternative recording medium can be used. While it is possible to restore the content from the backup data, it is possible to eliminate restrictions on moving the content even when using a plurality of recording media.

  Since the digital image recording / playback apparatus according to the fourth aspect of the present invention has the above-described configuration, the list to be restored does not disappear even when the power is not supplied, so that illegal content restoration can be avoided.

An example of an embodiment of a recording / reproducing apparatus according to the present invention will be described below with reference to FIGS.
FIG. 1 shows an example of a configuration of an embodiment of a digital image recording / playback apparatus according to the present invention. In contrast to the conventional configuration, a recording medium is used to distinguish between devices as input information to a backup information storage unit 26 and a KEY generation unit 16. It is configured with the added distinction information.

  FIG. 2 is a diagram for explaining the first embodiment, and is a diagram for explaining a case where the block configuration of FIG. 1 of the present invention is used. The boxes shown in the figure represent the data blocks of each recording medium, and in fact, a place where there are many data blocks is simply and imaged for explanation.

  STEP 1 in FIG. 2 shows a state in which there is no content in the built-in DVD medium and the formatting before recording is completed. A part of the data block is used for the file management information, and the rest is free. Generally, the file management information is not encrypted. Content 1, content 2, and content 3 have already been recorded in the built-in HDD. Part of the data block is used for File management information. Generally, the file management information is not encrypted. In some cases, it is used to manage content information. Generally, content management information is encrypted and recorded using a device-specific key (hereinafter referred to as “Deck_Key”). The content is also encrypted and recorded using Dec_Key. This indicates that the external HDDD has no content and the formatting before recording is completed. A part of the data block is used for the file management information, and the rest is free. Generally, the file management information is not encrypted. There is no information in the backup information storage unit 26.

  STEP 2 represents a state in which the contents 1 and 2 are backed up to the external HDD. The contents 1 and 2 are copied to the external HDD. Subsequently, the file management information is recorded reflecting the added state of the contents 1 and 2. The backup information storage unit 26 adds to the list that the contents 1 and 2 have been backed up.

  STEP 3 represents a state in which the content 2 is moved from the internal HDD to the internal DVD medium. After the content 2 is decrypted with the Deck_Key, it is encrypted according to a standard such as CPRM for recording on the DVD, recorded on the medium, and the file management information is updated. After the recording on the DVD is confirmed, the content management information and the file management information are updated in order to delete the content 2 from the internal HDD. Information indicating that the content 2 in the backup information storage unit 26 has been backed up becomes invalid and is deleted.

  STEP 4 shows the status of a series of results. If the built-in HDD becomes defective in this state and needs to be replaced, the state becomes STEP5. In the state of STEP5, the contents of the built-in HDD are the same as immediately after formatting, a part of the data block is used for File management information and content management information, and the rest are free.

  STEP 6 indicates a state in which the content that has been backed up is restored to be restored. When restoring, first, the backup information storage unit 26 is referred to and a list of backed up contents is referred to. Thereafter, referring to the file management information of the external HDD, the backed up content is found, and only those listed in the backup information storage unit are copied and restored. Specifically, since content 1 exists in the list, it can be restored. Since the content 2 has been moved to the DVD in the previous STEP 3, the backup is invalid, and since it has been deleted from the list in the backup information storage unit 26, the restore is not executed.

  If the control means using the backup information storage unit 26 according to the present invention is not used here, it is determined only by the state of being backed up to the external HDD, and when restoring to a new internal HDD, the content 2 is also restored. Content 2 exists in two locations, the internal HDD and the DVD, and copy management cannot be performed correctly in the case of copy-once content.

  FIG. 3 is a diagram for explaining the second embodiment and is a diagram for explaining a case where the block configuration of FIG. 1 of the present invention is used. In STEP 1 of FIG. 3, there is no content in the built-in DVD medium, and the format before recording is completed. A part of the data block is used for the file management information, and the rest is free. Contents 1 to 4 have been recorded in the built-in HDD. A part of the data block is used for file management information and content management information. In the content management information, a key generated from device-specific information for distinguishing devices (hereinafter referred to as “Deck_Key”) and a key generated from information specific to a recording medium for distinguishing HDDs (hereinafter referred to as HDD1_Key). ) Is encrypted and recorded. The content is also encrypted and recorded using Dec_Key and HDD1_Key. This indicates that the external HDDD has no content and the formatting before recording is completed. A part of the data block is used for the file management information and the content management information, and the rest is free. In the content management information, the device is encrypted and recorded using a key (hereinafter referred to as HDD2_Key) generated from information specific to the recording medium for distinguishing the device from Deck_Key and external HDD. There is no information in the backup information storage unit 26.

  In STEP 2, the contents 1 and 2 are backed up to the external HDD, and the contents 3 and 4 are moved to the external HDD. The contents 1 and 2 are temporarily decrypted using the Deck_Key and HDD1_Key at the time of reading and encrypted and recorded using the Deck_Key and HDD2_Key when copied to the external HDD. Similarly, the content 3 and the content 4 are once decrypted using the Deck_Key and the HDD1_Key at the time of reading and then encrypted and recorded using the Deck_Key and the HDD2_Key when copied to the external HDD. In the content management information, content 1 and content 2 are registered in a form indicating backup and content 3 and content 4 are moved. Subsequently, the file management information is recorded reflecting the added state of the content 1 to the content 4 and the update of the content management information.

  In the figure, the extension is backed up to distinguish between backup and move in an easy-to-understand manner. BAK Move is the original. This is expressed using TS. The backup information storage unit 26 adds to the list that the contents 1 and 2 have been backed up.

  STEP 3 represents a state in which the content 2 is moved from the internal HDD to the internal DVD medium, and the content 3 is moved from the external HDD to the internal HDD. Content 2 is decrypted with Deck_Key and HDD1_Key, then encrypted according to a standard such as CPRM for recording on a DVD, recorded on a medium, and File management information is updated. After the recording on the DVD is confirmed, the content management information and the file management information are updated in order to delete the content 2 from the internal HDD. Information indicating that the content 2 in the backup information storage unit 26 has been backed up becomes invalid and is deleted.

  The content 3 is read and decrypted with the Deck_Key and the HDD2_Key, and then encrypted again with the Deck_Key and the HDD1_Key and recorded on the built-in HDD for recording on the built-in HDD. In order to register the content 3, the content management information and file management information of the built-in HDD are updated. After the recording is confirmed in the internal HDD, the content management information and the file management information are updated in order to delete the content 2 from the external HDD.

  STEP 4 shows the status of a series of results. If the built-in HDD becomes defective in this state and needs to be replaced, the state becomes STEP5.

  In the state of STEP5, the contents of the built-in HDD are the same as immediately after formatting, a part of the data block is used for File management information and content management information, and the rest are free.

  STEP 6 indicates a state in which the content that has been backed up is restored to be restored. When restoring, first, the backup information storage unit 26 is referred to and a list of backed up contents is referred to. Thereafter, referring to the file management information of the external HDD, the backed up content is found, and only those listed in the backup information storage unit are copied and restored. Specifically, since content 1 exists in the list, it can be restored. Since the content 2 has been moved to the DVD in the previous STEP 3, the backup is invalid, and since it has been deleted from the list in the backup information storage unit 26, the restore is not executed.

  In this embodiment, a name for distinguishing the contents is used as the list information stored in the backup information storage unit 26. However, it is sufficient that the contents can be distinguished. In addition to content discrimination, it is possible to determine fraud such as tampering by storing together information for identifying HDDs used as backup sources and backup destinations.

FIG. 1 is a functional block diagram showing an embodiment of a digital image recording / reproducing apparatus according to the present invention. FIG. 2 is a diagram for explaining a first embodiment of the digital image recording / reproducing apparatus according to the present invention. FIG. 3 is a diagram for explaining a second embodiment of the digital image recording / reproducing apparatus according to the present invention. FIG. 4 is a functional block diagram showing a conventional digital broadcast receiving apparatus. FIG. 5 is a functional block diagram showing a conventional digital image recording / reproducing apparatus. FIG. 6 is a diagram for explaining the operation of a conventional digital image recording / reproducing apparatus. FIG. 7 is a diagram for explaining the operation of a conventional digital image recording / reproducing apparatus.

Explanation of symbols

01 antenna 02 control unit 03 memory 04 tuner 05 descrambler 06 buffer control unit 07 VIDEO decoder unit 08 display device 09 IEEE1394 I / F unit 10 encryption unit (DTCP)
11 TS-DEMUX
12 AUDIO decoder part 13 Speaker 14 Cryptographic part (CPRM)
15 Cryptographic part (LOCAL method)
16 KEY generation unit 17 ATAPI I / F unit 18 HDD I / F unit 19 Built-in DVD
20 Internal HDD
21 LAN I / F unit 22 USB I / F unit 23 DVD recording medium 24 LAN connection HDD
25 USB connection HDD
26 Backup information storage unit

Claims (5)

A recording / reproducing apparatus that records content such as video data on a recording medium, reads the recorded content from the recording medium, and reproduces the content,
Means for generating information for distinguishing each device;
Means for performing encryption based on information that is differentiated for each device when recording content;
Means for recording the encrypted content on a recording medium;
Means for backing up content from one recording medium to the other having a plurality of recording media;
A means of maintaining a list of backed up content;
Means for restoring content while judging using a list of contents that were backed up when the recording medium was replaced due to failure;
A digital image recording / reproducing apparatus comprising: A recording / reproducing apparatus that records content such as video data on a recording medium, reads the recorded content from the recording medium, and reproduces the content,
Means for generating information for distinguishing each device;
Means for generating information for making a distinction for each recording medium for recording;
Means for performing encryption based on information for distinguishing each device when recording content and information for distinguishing a recording medium for recording content;
Means for recording the encrypted content on a recording medium;
A digital image recording / reproducing apparatus comprising: A recording / reproducing apparatus that records content such as video data on a recording medium, reads the recorded content from the recording medium, and reproduces the content,
Means for generating information for distinguishing each device;
Means for generating information for making a distinction for each recording medium for recording;
Means for performing encryption based on information for distinguishing each device when recording content and information for distinguishing a recording medium for recording content;
Means for recording the encrypted content on a recording medium;
Means for backing up content from one recording medium to the other having a plurality of recording media;
A means of maintaining a list of backed up content;
Means for restoring content while judging using a list of contents that were backed up when the recording medium was replaced due to failure;
A digital image recording / reproducing apparatus comprising: The digital image recording / reproducing apparatus according to claim 1 or 3,
To maintain a list of backed up content,
A digital image recording / reproducing apparatus using a non-volatile memory. The digital image recording / reproducing apparatus according to any one of claims 1 to 4,
A digital image recording / reproducing apparatus, wherein the recording medium is an HDD.