JP2008072724A - Signal receiver, and signal reception method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent information that is output to an external device from an information output device from being used for a purpose other than an original purpose, and from giving disadvantages to the producer and copyright holder of the information. <P>SOLUTION: When it is recognized that the external device operates according to copy control information, digital information is output with the original quality. When it is not recognized that the external device operates according to the copy control information, copy-limited information is not output. The method can also be applied to, for example, the operation of the output board of a personal computer. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an information output device that receives and outputs digital information such as video and audio, an information reception device, an information output method, and an information transmission method. The present invention relates to an apparatus and a method for giving restrictions on recording to a recording medium or outputting from an apparatus.

  In the field of television broadcasting, recording and playback devices, and packaged media such as movie software, digital broadcasting has begun, and consumer-use receivers, display devices, and digital recording / playback devices corresponding to this have been released. Has been. Package software for this device will appear in the near future. The advantage of digital broadcasting and digital recording devices is that there is no or very little quality degradation in the information transmission process and recording / reproduction process. However, there are problems in that many good quality copies of information are made around the place where the copyright holder does not know, and when the copy is repeated, profits are not returned to the copyright holder.

  U.S. Pat. US Pat. No. 5,896,454 discloses a method of attaching 2-bit copy control information to information. This is because the copyright owner and the creator of the information can select one of three methods: copy prohibition (Copy Never), copy authorization (Copy Free), and one-generation copy authorization (Copy One Generation). It controls the operation of the recording apparatus. The recording device does not perform the recording operation if the copy is prohibited, and performs the recording operation if the copy is authorized. If copying is permitted for only one generation, the recording apparatus rewrites this control information to information that disallows copying any more (No More Copies), and then performs a recording operation.

US Pat. No. 5,896,454

  The matter disclosed in the above prior art defines the operation on the recording apparatus side when the given information is supplied to the recording apparatus. However, there are further considerations when receiving from a receiving device or playing back from a playback device and outputting from the device to the outside.

  It goes without saying that the output operation to the outside of the device is necessary for supplying information to the display, but it must be considered that it may be used for purposes other than display. Once it is output via the device, it must be considered that it does not accompany the copy control information described above, but even if it is accompanied by copy control information, the receiving device operates according to the copy control information. Not always. It may be output as a digital signal, or it may be after conversion to analog. For example, in a current PC (Personal Computer), when receiving with a tuner board and outputting to a display via a graphic board, it outputs with an analog RGB signal and does not accompany copy control information.

  If these outputs are used for purposes other than display, there is a possibility that a copy of the output may be made, which is disadvantageous to the copyright holder. This is not mentioned in the above mentioned literature.

  In view of the above problems, an object of the present invention is to provide a method and an apparatus for outputting information to the outside without causing a disadvantage to the copyright holder.

  In order to achieve the above object, in the information output device for outputting the input digital video information or the digital video information reproduced from the storage medium to an external device in the present invention, the information is added to the digital video information. A control information detection circuit for detecting control information including at least copy control information; a first output circuit for outputting the digital video information to an external device; and converting the digital video information into an analog video signal to the external device. A second output circuit for outputting, and a control circuit for controlling the output of the first output circuit and the second output circuit in accordance with the control information detected by the control information detection circuit. .

  An information output device according to the present invention includes a control information detection circuit that detects control information added to digital video information, an output circuit that outputs digital video information to an external device, and the external device or the output circuit. A state recognition circuit for recognizing the state; and an output control circuit for controlling the output of the output circuit. The output control circuit is configured to control the output circuit based on the control information detected by the control information detection circuit and the state of the external device or output circuit recognized by the state recognition circuit.

  Here, the control information is information relating to copy restriction of digital video information or protection of the video information. When the state recognition circuit cannot recognize the state of the external device or the output circuit and the control information designates the copy restriction of the digital video information or the protection of the video information, the output control circuit Stops output from the output circuit. Recognition of the state of the external device or the output circuit by the state recognition circuit includes authentication using a key signal with the external device or the output circuit.

  In order to achieve the above object, in the information receiving apparatus for receiving digital video information and outputting it to an external device in the present invention, a receiving unit for receiving the digital video information, and the digital video information added to the received digital video information, A control information detection circuit for detecting control information including at least copy control information; a first output circuit for outputting the digital video information to an external device; and converting the digital video information into an analog video signal to the external device. A second output circuit for outputting, and a control circuit for controlling the output of the first output circuit and the second output circuit in accordance with the control information detected by the control information detection circuit. .

  To achieve the above object, an information output method for outputting input digital video information or digital video information reproduced from a storage medium from a first device to a second device according to the present invention comprises: Detecting the control information added to the first device, and recognizing the state of the first device or the second device. The detected control information and the recognized first device or the second device. The output from the first device is controlled based on the state of the second device.

  In order to achieve the above object, in the information transmission method for transmitting digital video information to the information receiving device in the present invention, control information including at least copy control information is added to the digital video information to be transmitted, The control information controls the output signal when the information receiving device converts the digital video information into an analog video signal and outputs the analog video signal to an external device.

  According to the present invention, there is provided an information transmission method for transmitting digital video information to an information output device that inputs information and outputs it to an external device. The digital video information to be transmitted includes a digital video information copy restriction or video information. Add control information about protection of This control information is used in combination with the result of recognizing the state of the information output device or the external device to control the output of digital video information when outputting the digital video information from the information output device to the external device. Used for.

  As described above, the present invention has an effect that information output from the apparatus to the outside is used unintentionally, and the problem that disadvantages the copyright holder can be solved. When applied to a PC board, there is an effect that the output method cannot be protected by the replacement.

Hereinafter, embodiments of the present invention will be described with reference to the drawings as necessary.
The present invention particularly relates to a method for outputting information, and an object of the present invention is to eliminate certain disadvantages for the copyright holder by providing certain restrictions thereto. The embodiment is particularly shown in FIGS. 4 to 10, but before the description, the whole system to which the present invention is applied will be described.

  FIG. 1 is a block diagram showing an example of an embodiment of the entire system used in the present invention, and shows an example in which information is transmitted / received by broadcast and recorded / reproduced. This includes devices to which the present invention is applied. Reference numeral 1 is an information providing station such as a broadcasting station, 2 is a relay station, 3 is a receiving device, 4 is a first recording / reproducing device, 5 is a display, and 6 is a second recording / reproducing device. Here, when broadcasting information or the like is recorded, it can be recorded on at least one of the first recording / reproducing apparatus 4 and the second recording / reproducing apparatus 6 according to the copy control information attached thereto. The first recording / reproducing apparatus 4 is described here as being based on a digital recording system built in the receiving apparatus 3. As the recording medium, for example, a hard disk that cannot be removed can be used. A video disc, video tape, or the like that can be removed may be used, but a recording / reproducing device built in the receiving device is often used when information is stored for a relatively short period of time, and therefore may not be removable. Here, the second recording / reproducing apparatus 6 will be described as being externally attached to the receiving apparatus 3. In addition to the hard disk, removable media such as a magnetic tape and an optical disk may be used as the recording medium. It should be noted that the present invention can be applied even if either or both of the first recording / reproducing apparatus 4 and the second recording / reproducing apparatus 6 do not exist.

  An information providing station 1 such as a broadcasting station transmits a signal radio wave modulated by information via a relay station 2 such as a broadcasting satellite. In addition, transmission by cable, transmission by telephone line, transmission by terrestrial broadcasting, or the like may be used. As will be described later, this signal radio wave received by the receiving device 3 on the receiving side is demodulated into an information signal, and then to the first recording / reproducing device 4 and the second recording / reproducing device 6 as necessary. It is recorded as a signal suitable for recording. Also, it is sent to the display 5. Here, the user can directly view the information content. The information reproduced by the first recording / reproducing apparatus 4 and the second recording / reproducing apparatus 6 is given to the display 5 via the receiving apparatus 3 and the information such as the original video / audio is viewed.

  There are various types of information to be transmitted. For example, even in the case of television broadcasting, when there are a large number of scanning lines, HD (High Definition) broadcasting exceeding 1000 lines and SD (Standard Definition) broadcasting of about 500 lines. and so on. Therefore, on the receiving side, a plurality of broadcasting systems are supported if necessary. Further, control information indicating which broadcasting system is used may be transmitted by adding to the information in the same manner as the previous copy control information.

  The receiving apparatus 3 is not intended only for an apparatus called STB (Set Top Box) specialized for broadcast reception. A PC having a tuner board or a graphic board may be used. In this case, the first recording / reproducing apparatus 4 corresponds to the hard disk drive and its peripheral circuits. As will be described later, the receiving device 3 itself may include a display unit corresponding to the display 5.

  When a removable recording medium in which information is recorded in advance, for example, package software, is provided, the reproduction operation and the like in, for example, the second recording / reproducing apparatus 6 attached thereto is performed. In this case, the information providing station 1 and the relay station 2 are excluded, but the present invention can also be applied.

  Information is often exchanged between devices using digital signals. For example, the receiving device 3 and the display 5 may be connected using analog signals. In some cases, the luminance and the two color difference signals are used for connection, and in the case of the PC, the RGB signals are used for connection.

  FIG. 2 is a block diagram showing a configuration example of the information providing station 1 such as a broadcasting station in the above system. Reference numeral 11 denotes a source generation unit, 12 denotes an encoding circuit that performs compression by the MPEG method, 13 denotes a scramble circuit, 14 denotes a modulation circuit, 15 denotes a transmission antenna, 16 denotes a management information addition circuit, and 17 denotes an input terminal.

  Information such as video and audio generated by the source generation unit 11 including a camera and a recording / reproducing device is compressed by the encoding circuit 12 so that it can be transmitted in a smaller occupied band. If necessary, the scramble circuit 13 performs transmission encryption so that only a specific viewer can view. After being modulated by the modulation circuit 14 so as to be a signal suitable for transmission, the signal is emitted from the transmission antenna 15 as a radio wave toward the relay station 2 such as a broadcasting satellite. At this time, the management information adding circuit 16 adds the above-described copy control information, information indicating the broadcasting system, and the like. Furthermore, in order to protect the information, control information (EPN: Encryption Plus Non-assertion) indicating whether or not to limit the quality at the time of output can be sent. Further, although omitted from FIG. 1 above, for example, request information is input from the input terminal 17 via a telephone line or the like. This is utilized in a system for determining information to be transmitted in response to a viewer's request such as video on demand.

  In practice, a plurality of information is often multiplexed in one radio wave by a method such as time division or spread spectrum. Although not shown in FIG. 2 for simplicity, in this case, there are a plurality of systems of the source generation unit 11 and the encoding circuit 12, and a multiplex for multiplexing a plurality of information between the encoding circuit 12 and the scramble circuit 13. A circuit is placed.

  FIG. 3 is a block diagram showing an example of the configuration of the receiving device 3 in the system of FIG. Reference numeral 301 denotes an RF / IF conversion circuit, 302 a demodulation circuit, 303 an error correction circuit, 304 a descrambling circuit for canceling the transmission encryption applied to the signal, 305 a first demultiplexing circuit, and 306 an input / output terminal 307 is a second demultiplexing circuit, 308 is a decoding circuit, 309 and 310 are output terminals, 311 is a control circuit for controlling the entire receiving apparatus 3, 312 is an information management circuit, 313 is a command input circuit, and 314 is Input terminal. Reference numeral 4 denotes a first recording / reproducing apparatus, which is incorporated in the receiving apparatus 3 as described in FIG. In the figure, the solid line indicates the flow of main information such as video and audio, and the dotted line indicates the flow of control signal information between the components.

  First, the flow of information such as video and audio indicated by solid lines will be described with respect to the components 301 to 310. For example, radio waves from a relay station such as a broadcasting satellite are input to the RF / IF conversion circuit 301. Here, the radio wave in the RF band is frequency-converted to an IF band (Intermediate Frequency), becomes a signal in a certain band independent of the reception channel, and the modulation operation performed for transmission by the demodulation circuit 302 is demodulated. Further, after an error in the code generated during transmission is detected and corrected by the error correction circuit 303, the descrambling circuit 304 releases the transmission cipher. Thereafter, the data is sent to the first and second demultiplexing circuits 305 and 307. As described above, particularly in the case of digital broadcasting, a plurality of information is often multiplexed on one channel by a method such as time division or spread spectrum. The demultiplexing circuit separates only desired information from this. The reason why the two demultiplex circuits are provided is not only to enable so-called back program recording but also to remove information not worth recording in the first demultiplex circuit 305. In other words, additional information such as weather forecasts, program broadcast schedules, etc. is often included in the information, which is good to see at the time of broadcasting, but it is not worth recording and seeing at a later date. It can also be removed.

  The output of the first demultiplexing circuit 305 is given to the first recording / reproducing apparatus 4. The signal is also given to the input / output terminal 306 and exchanges signals with the second recording / reproducing apparatus 6 connected thereto. The input / output terminal 306 is a bidirectional terminal, and exchanges information to be recorded / reproduced with the second recording / reproducing apparatus 6 as digital data, for example. In general, connection according to the IEEE 1394 standard is often used.

  In the first recording / reproducing apparatus 4 and the second recording / reproducing apparatus 6, when there is an operation instruction to record information, the copy control information attached to the given information is Copy Never or No More Copies. Indicates that no recording is performed. If it is Copy One Generation, record this after rewriting it as No More Copies. If it is Copy Free, record directly. In addition to this, record the information that is No More Copies on the condition that the information that is Copy Never is temporarily recorded and the original information source is made unreproducible, with a limited period of playback. May be permitted.

  The second demultiplexing circuit 307 includes information sent from the descrambling circuit 304, information reproduced by the first recording / reproducing device 4, or a second recording / reproducing device from the input / output terminal 306. The information reproduced in step 6 is connected, and information to be viewed is selected, and desired information is further separated. In the next decoding circuit 308, the data compression of the moving image performed before the transmission is decoded, and further subjected to processing as described later with reference to FIGS. 4 and 5, and then via the output terminals 309 and 310. Sent to an external device. As will be described later, there may be a case where one output terminal is sufficient, but here, the case where there are two output terminals is shown. The information signals at the output terminals 309 and 310 may be either digital or analog, but here the former is digital output and the latter is analog output.

  Next, control signals indicated by dotted lines will be described. The control circuit 311 exchanges control signals with the components 305, 307, and 308 from the above 301, and controls the entire receiving apparatus 3 to perform a desired operation. The information management circuit 312 supplies management data when the control circuit 311 performs control in response to a request. For example, reception contract information is managed here. When the user designates a channel to be viewed, this designation is input from the input terminal 314 and sent to the control circuit 311 via the command input circuit 313. The control circuit 311 requests the reception contract information from the information management circuit 312. When it is determined that there is a contract with the channel designated by the user, a control signal is sent to each of the above-described components, and a control operation such as instructing a reception operation of the corresponding channel is performed.

  When the first recording / reproducing device 4 is built in the receiving device 3, a recording / reproducing operation is performed in accordance with a user instruction input from the input terminal 314. For this reason, the output of the command input circuit 313 is supplied. This control signal may be supplied from the control circuit 311.

  Next, with reference to FIGS. 4 and 5, a method for outputting information which is the center of the present invention will be described. These are circuit block diagrams showing an embodiment of the present invention, and show the internal configuration of the decoding circuit 308 of FIG. 30801 is an input terminal, 30802 is a decoding circuit, 30803 is a control detection circuit, 30804 is an up-conversion circuit, 30805 is a down-conversion circuit, 30806 is a switch, 30807 is a resolution limiting circuit, 30808 is an RGB conversion circuit, 30809A and B are switches, Reference numeral 30810 denotes an information protection circuit. Reference numerals 309 and 310 denote output terminals, which are also shown in FIG. Here, 310 is an output terminal for RGB signals, but is not limited thereto. Alternatively, the RGB conversion circuit 30808 may be moved immediately after the switch 30806, and 309 may be used as an RGB signal output terminal.

  The output from the second demultiplexing circuit 307 in FIG. 3 is given to the input terminal 30801 in FIG. The decoding circuit 30802 decodes and decompresses the data compression of the moving image performed before transmission. The output is given to one terminal of the switch 30806 (hereinafter referred to as A terminal), the up-conversion circuit 30804, and the down-conversion circuit 30805. The output of the up-conversion circuit 30804 is given to the B terminal of the switch 30806, and the output of the down-conversion circuit 30805 is given to the C terminal of the switch 30806.

  On the other hand, the output of the previous decoding circuit 30802 is also given to the control detection circuit 30803, where each control information including the copy control information and the control information indicating the broadcasting system is detected, and the result is Connection of the switch 30806 is determined. Here, for the sake of completeness of the drawing, the decoding circuit 308 has the control detection circuit 30803 uniquely. However, for example, the control circuit 311 in FIG. good. The connection of the switch 30806 will be described later.

  The output of the switch 30806 is given to the output terminal 309 via the information protection circuit 30810 and the switch 30809A and is output to an external device only when it is connected. Further, the resolution is given to the resolution limiting circuit 30807, and the horizontal resolution is limited if necessary according to the control signal. In many cases, it is transmitted as a luminance / two-color difference signal up to this stage, but it is further converted into an RGB signal by the RGB conversion circuit 30808, and given to the output terminal 310 only when it is connected via the switch 30809B. And output to an external device. Although information is output from the output terminal 310 as an analog signal, although not shown, a DAC (Digital Analogue Converter) is placed anywhere in front of it. Note that the resolution may be limited not only to the horizontal resolution but also to the vertical resolution. Further, the resolution may be limited at the time of decoding by the decoding circuit 30802.

  A method of switching the operations of the switches 30806, 30809A, B, the resolution limiting circuit 30807, and the information protection circuit 30810 according to the control signal will be described.

  In one embodiment of the present invention, when information is output from the apparatus to the outside, it is added to prevent the copyright holder from being disadvantaged because it is used for purposes other than display on the display. According to the control information, the quality of output information, the number of pixels, the resolution, and the like are changed. HD information has many scanning lines and horizontal pixels, and can reproduce high-quality images. However, if this is used for a purpose other than the intended purpose, a copy or the like that can ensure a certain quality will be accepted, which will cause a disadvantage for the copyright holder. On the other hand, if the quality is lower than the conventional SD method, such a problem is unlikely to occur. As one guideline, there is no problem as long as it is 520,000 pixels or less per frame, for example, about 480 effective scanning lines and about 720 to 960 horizontal pixels. Therefore, it is preferable that the quality is limited to protect the information as necessary and output from the apparatus to the outside.

  In the present invention, the situation of the output destination connected to the output terminal 309 is also considered. If the above-described copy control information is added and the output destination device is a device that operates in accordance with the copy control information, it is not necessary to limit the quality of the output information as described above. A method of knowing what device the output destination device is is not described in detail here, but means called device authentication is used. This is to know a partner device by exchanging a key signal between both devices. Although the signal flow is not shown, control information is output from the control circuit 311 to the control detection circuit 30803 in accordance with the authentication result, and the switch 30806 and the like are controlled. If authentication is established and the output destination is the device described above, the switch 30806 is connected to the A terminal, the switch 30809A is closed, and the output of the decoding circuit 30802 is supplied to the output terminal 309 via the information protection circuit 30810. It is done. When the information is SD information, it may be required to be apparently HD information. In this case, it is preferable to connect the switch 30806 to the B terminal and output information via the up-conversion circuit 30804.

  Information protection in the information protection circuit 30810 may always be performed regardless of the copy control information. In this case, when it is confirmed by authentication that the device is compatible with the output destination, it is always output with protection, and when it is not confirmed, it is output without protection. Further, in the case of outputting for display, it is sufficient that protection is performed, and it is not necessary to perform copy control. Therefore, it is not necessary to add copy control information.

  In the information protection circuit 30810, an operation for protecting output information is performed as necessary. For example, it is scrambled using a device-specific number that uses information, a user identification number, and the like. In this way, the risk of unintended use of the output information is further reduced. If the detected copy control information is Copy Free, the operation may be switched in accordance with a control signal from the control detection circuit 30803, such as not scrambled otherwise, and scrambled to enhance protection in other cases.

  Next, a description will be given of a case where the output destination device is a device that does not operate in response to the copy control information while the copy control information is added, or when the copy control information is not added. In this case, if the detected copy control information is Copy Free, the switch 30809A is closed and the information is output. If not, the circuit is opened and no information is given to the output terminal 309. Copy Free originally means that the producer does not strongly claim rights, so there is no problem even if it is output, but in other cases there is a right problem, so output in the form that the copy control information does not work Not performed. Thereby, there is an effect that output information from the apparatus is not used unintended. On the other hand, at the output terminal 310, information having a certain quality limit is output. That is, if the copy control information is Copy Never, Copy One Generation, or No More Copies, the switch 308 is connected to the C terminal and the switch 30809B is closed. The number of scanning lines is reduced by the down-conversion circuit 30805, the number of horizontal pixels is reduced by the resolution limiting circuit 30807, and information that is about 520,000 pixels or less per frame is supplied to the output terminal 310. For example, this is not high-quality information such as HD information, and therefore, there is an effect that even if information output to the outside is used for a purpose other than the purpose, there is no disadvantage to the copyright holder.

  In the future, separately from the copy control information, when outputting from the apparatus to the outside, it is conceivable to send control information indicating whether or not to perform quality restriction for protecting the above information (EPN; Encryption Plus) Called non-assertion). Even when this is instructed to limit the quality, the information protection circuit 30810 including the operation may be handled in the same manner as information other than the above-mentioned copy free.

  In the above description, the output is made only to the output terminal 309 if the copy control information is Copy Free, and only to the output terminal 310 if Copy Never, Copy One Generation, or No More Copies. This is shown as an example in view of the fact that the current graphic board has only one output. Therefore, one output terminal may be used, and the switches 30809A and 30809B may be replaced by one two-point selection type switch.

  In addition, it may not be preferable to attach a switch to the route through which the information signal is transmitted because of loss. In this case, instead of providing a plurality of routes and switching them with a switch, a method is used in which the hot plug is removed and the circuit operation itself is reset. When this is used, the output of the information output until then is stopped, and after the predetermined time has elapsed, the other output is started.

  On the other hand, in FIG. 5, output information is always given to the output terminal 310, and only the output terminal 309 side changes the presence or absence of output by the operation of the switch 30809A. The operation of other components is the same as that in FIG. When the copy control information is Copy Free, information not subject to quality restrictions is also output to the output terminal 310. In this case, the output terminals 309 and 310 may be separate or housed in one connector.

  If the copy control information is Copy Free, the output is output only to the output terminal 309. Otherwise, the output having the digital input and the analog input is output to the output terminal 309 and the analog input is output. If the output of the terminal 310 is connected, a high-quality digital signal can be displayed with Copy Free, and an analog signal can be displayed with any other signal.

  FIG. 6 collectively shows the operations described above. When the copy control information functions in the output destination device on the output terminal 309 side, the information is output without performing quality restriction, including the case where there is control information instructing the EPN. If the copy control information does not work, the information is output without quality restriction in the case of Copy Free, but not output otherwise. On the other hand, on the output terminal 310 side which is RGB output, in the case of Copy Free, the information is output without quality limitation. In other cases, the quality is limited, and the number of scanning lines, the horizontal resolution, etc. Information is limited and the number of pixels is limited to 520,000 pixels or less.

  As described above with reference to FIG. 4, if there is an output on the 309 side, the 310 side may not output. For example, this corresponds to the case where the output terminal has one system.

Next, a case where the receiving device 3 in FIG. 2 has a display unit corresponding to the function of the display 5 will be described. An embodiment of the decoding circuit 308 in this case is shown in the circuit block diagram of FIG. Reference numeral 7 denotes a display unit built in the receiving device 3. That is, the output of the decoding circuit 30802 is given to the display unit 7. If necessary, this and the output of the up-conversion circuit 30804 may be switched and given. Since this connection is made inside the receiving apparatus 3, it is not necessary to apply the quality restriction as described above. On the other hand, the outputs from the output terminals 309 and 310 are so-called monitor outputs, but are supplied to the outside of the apparatus, so the quality restriction as described above is performed.
In this case, the receiving device 3 can be called a receiving / display device with a recording or storage function, but of course, the first recording / reproducing device 4 does not exist and can be applied to a case where a recording function is not incorporated.

  FIG. 11 is a block diagram showing an embodiment when a digital RGB signal is output to the output 309. The output 309 outputs the digital RGB signal generated by the RGB conversion circuit 30808 as it is or after protecting the information by the information protection circuit 30810. In the output 310, the digital RGB signal generated by the RGB conversion circuit 30808 is converted into an analog RGB signal by the D / A converter 3082 and output.

  FIG. 12 shows the output operation of the outputs 309 and 310. When output protection functions in the output destination device on the output terminal 309 side, information is output without performing quality restriction, including the case where there is control information instructing the EPN. When the output protection does not function, the information is output without limiting the resolution in the case of Copy Free. In other cases, the output is prohibited or output with the resolution limited. When output protection does not function, it is possible to perform more complete protection by prohibiting output. However, by limiting the resolution and outputting, it is possible to connect to a conventional device having no protection function. On the other hand, on the output terminal 310 side, in the case of Copy Free, the information is output without limiting the resolution. In other cases, the information is output with the resolution limited or output as it is. In other cases, output may be prohibited. In this case, it becomes impossible to connect to a conventional device that can only perform analog connection, but more complete protection can be performed.

  FIG. 8 is a block diagram showing still another embodiment of the present invention. In FIG. 1, it has been described that the receiving device 3 may be a PC having a tuner board and a graphic board. In FIG. 8, 8 is a PC, 801 is an input terminal, 802 is a tuner board, 803 is a graphic board, 804 is a CPU board, 80401 is a CPU (Microcomputer), 80402 is flash memory, 80403 is RAM (Random Access Memory), 80404 Is an interface circuit, 805 is an input terminal, 806 is a hard disk drive, and 807 is an output terminal.

  The first recording / reproducing apparatus 4 in FIGS. 1 and 3 corresponds to the hard disk drive 806 and its peripheral circuits. Also, the components 301 to 307 in FIG. 3 are on the tuner board 802, and 308 to 310 are on the graphic board 803. Of these, both or one of the output terminals 309 and 310 corresponds to the output terminal 807. The control circuit 311 corresponds to the CPU 80401, and the information management circuit 312 corresponds to the readable / writable flash memory 80402. In addition to this, RAM 80403 is also provided as an external memory of the CPU. The command input circuit 313 and the input terminal 314 correspond to an interface circuit 80404 such as a mouse and a keyboard and an input terminal 805 thereof. Therefore, the present invention can also be applied to graphic output of a PC. This example will be described with reference to the circuit block diagrams of FIGS.

FIG. 9 corresponds to FIG. 4 above, and an input / output terminal 30811 and an authentication circuit 30813 are added, and the function of the previous control detection circuit 30803 is assumed to be performed by the control circuit 311 of FIG. The difference is that the result is given from the input terminal 30812. Furthermore, the control from the input terminal 30812 is not necessarily limited to hardware such as a control signal, and software control may be used. Each component in FIG. 9 is on the graphic board 803 in FIG. 8 as described above. If the decoding circuit 30802 is placed on the tuner board 802 in the same manner as the components 301 to 307 in FIG. 3 by changing the cut end, the broken lines in the figure become the cut ends of both boards.
FIG. 10 corresponds to FIG. 5 above, but is otherwise the same as FIG.

  These operations will be described with reference to FIG. Prior to outputting information from the output terminals 309 to 310, the control circuit 311 in FIG. 3 first sends an authentication key for authenticating the board to the authentication circuit 30813 via the input / output terminal 30811. The authentication circuit 30813 sends the authentication key back to the control circuit 311 if this authentication key matches a predetermined one. The key to send back does not have to be the same as the received key, but of course what is sent is predetermined. If the key received by the control circuit 311 is a predetermined key, this graphic board can be authenticated as a board performing an expected operation. If the key is different and nothing is sent back, authentication fails. The expected operation is the quality restriction of the information to be output described above with reference to FIGS. 4, 5, and 6.

  If the authentication is successful, the control circuit 311 continues to request and notify the authentication circuit 30813 of the type of information to be output. The type of information indicates whether to perform digital output with control information added, digital output with no control information added, or analog RGB output in particular. If necessary, the information protection circuit 30810 checks whether information is protected. In response to this, the control circuit 311 controls the operation as follows. When control information such as copy control information is added, the digital output is output with the copy free information as it is and the other information encrypted as necessary to protect the information. When control information is not added, digital output is not output except for Copy Free information. For analog output, the information of Copy Free is output as it is, and the other information is output with quality limited to about 520,000 pixels or less, for example. In FIG. 9, as with FIG. 4, there may be only one output depending on the board. For example, the copy free information is digital as it is, and the other information is output with analog quality limited. It ’s fine.

  If authentication is not successful, no information other than Copy Free information is output, whether digital or analog.

  By doing in this way, it can reduce that the information output from a graphic board is used for the purpose outside. Further, in the PC, the board is designed so that the user can arbitrarily replace it, but there is no possibility that these output methods will not be protected by the replacement.

  As another method, a case will be described in which the authentication circuit 30813 does not have an authentication function but has only a function of notifying the type of information to be output. At this time, the control circuit 311 controls the operation as follows.

  First, when you know the type of information, if control information such as copy control information is added, the digital output will remain the Copy Free information as it is, and other information will be protected as necessary. Encrypted for output. When control information is not added, digital output is not output except for Copy Free information. For analog output, the information of Copy Free is output as it is, and the other information is output with quality limited to about 520,000 pixels or less, for example.

  If the type of information is not known, it is recognized as a non-standard board, and no information other than Copy Free information is output, whether digital or analog. In this case, since an authentication key is not used, security is less than in the previous example, but in general, this is often sufficient.

  In the above description, when output from the output terminal of the apparatus is not performed, character information indicating that no output is performed may be output instead of outputting nothing to the display unit. Of course, the character information may be output only for the originally specified time and then deleted. For example, in FIG. 4, an OSD (On Screen Display) circuit for this purpose is placed between the output terminals 309 and 310 and the switches 30809A and 30B as necessary, and is controlled by the control circuit 311 or the like to transmit character information. Output.

1 is a block diagram showing an embodiment of an entire system to which the present invention is applied. The block diagram which shows the structural example of information provision stations 1, such as a broadcasting station in FIG. The block diagram which shows the structural example of the receiver 3 in FIG. 1 is a block diagram illustrating an example of a configuration of a decoding circuit to which the present invention is applied. 1 is a block diagram illustrating an example of a configuration of a decoding circuit to which the present invention is applied. The figure for demonstrating the output information in this invention. The block diagram which shows an example of a structure of the decoding circuit and display part to which this invention is applied. The block diagram which shows an example of a structure of PC to which this invention is applied. The block diagram which shows an example of a structure of the graphic board to which this invention is applied. The block diagram which shows an example of a structure of the graphic board to which this invention is applied. The block diagram which shows another example of a structure of the decoding circuit to which this invention is applied. The figure for demonstrating the output information in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Information providing station 16 such as a broadcasting station ... Management information giving circuit 2 ... Relay station 3 ... Receiving device 308 ... Decoding circuit 311 .... Control circuit 30803 ... Control detection circuit 30805 ... Down conversion circuit 30806 ... Switch 30807 ... Resolution limiting circuit 30808 ... RGB conversion circuit 30809A ... Switch 30809B ... Switch 30810 ... Information protection circuit 30803 Circuit 4... First recording / reproducing apparatus 5... Display 6... Second recording / reproducing apparatus 7.・ PC
802 ... Tuner board 803 ... Graphic board 804 ... CPU board 80401 ... CPU
80402 ·· Flash memory 80403 · · RAM
80404 .. Interface circuit 806... Hard disk drive

In order to achieve the above object, for example, in an information receiving apparatus that receives a digital broadcast signal that has been compressed and broadcast and outputs the signal to the outside, a receiving unit that receives the digital broadcast signal, and a digital signal received by the receiving unit Decoding means for decoding the control signal, control information detecting means for detecting control information including at least copy control information added to the digital broadcast signal received by the receiver, and the digital broadcast signal decoded by the digital code means Output means for outputting as a digital video signal or analog video signal, and control means for controlling the output of the output means in accordance with the control information detected by the control information detecting means, wherein the control means comprises the control information The digital broadcast signal specifies copy restrictions or video information protection. In this case, the output of the digital video signal is output only when the protection is carried out, in the output of the analog video signal can not copy control adopts a configuration that outputs the limit resolution.

The above object can be achieved by, for example, the configuration described in the claims.

Claims (29)

An information output device for outputting input digital video information or digital video information reproduced from a storage medium to an external device,
A control information detection circuit for detecting control information including at least copy control information added to the digital video information;
A first output circuit for outputting the digital video information to an external device;
A second output circuit for converting the digital video information into an analog video signal and outputting the analog video signal to an external device;
A control circuit for controlling the outputs of the first output circuit and the second output circuit in accordance with the control information detected by the control information detection circuit;
An information output device comprising:   The control circuit selects either the first output circuit or the second output circuit in accordance with the control information, and switches and outputs the digital video information and the analog video signal. The information output device according to claim 1.   The control circuit selects the second output circuit to output the analog video signal when copy restriction or video information protection is specified by the control information, and when not specified, 3. The information output apparatus according to claim 2, wherein the digital image information is output by selecting the first output circuit.   The control circuit starts outputting the other output after a predetermined period of time has elapsed after stopping the output of one of the first output circuit and the second output circuit in accordance with the control information. The information output device according to claim 2.   2. The information output apparatus according to claim 1, wherein the control circuit stops outputting the digital video information from the first output circuit in accordance with the control information.   6. The control circuit according to claim 5, wherein when the control information specifies copy restriction or video information protection, the control circuit stops outputting the digital video information from the first output circuit. The information output device described in 1.   2. The information output apparatus according to claim 1, wherein the control circuit limits a resolution of the analog video information from the second output circuit in accordance with the copy control information.   The control circuit limits the resolution of the analog video information from the second output circuit when copy restriction or video information protection is specified by the control information. The information output device described in 1. An information protection circuit for protecting digital video information output from the first output circuit;
2. The information output apparatus according to claim 1, wherein when the digital video information output from the first output circuit is protected, the digital video information is output regardless of the content of the control information.   10. The information output apparatus according to claim 9, wherein the information protection circuit protects the digital video information output from the first output circuit by scrambling.   2. The information output apparatus according to claim 1, wherein the digital video information output from the first output circuit and the analog video signal output from the second output circuit are RGB signals. .   12. The information output according to claim 11, wherein the digital video information output from the first output circuit and the analog video signal output from the second output circuit are output from the same connector. apparatus. An information receiving device for receiving digital video information and outputting it to an external device,
A receiver for receiving the digital video information;
A control information detection circuit for detecting control information including at least copy control information added to the received digital video information;
A first output circuit for outputting the digital video information to an external device;
A second output circuit for converting the digital video information into an analog video signal and outputting the analog video signal to an external device;
A control circuit for controlling the outputs of the first output circuit and the second output circuit in accordance with the control information detected by the control information detection circuit;
An information receiving apparatus comprising:   14. The information receiving apparatus according to claim 13, further comprising a display unit that displays digital video information received by the receiving unit. In an information transmission method for transmitting digital video information to an information receiving device,
Control information including at least copy control information is added to the digital video information to be transmitted,
The information transmission method according to claim 1, wherein the control information controls the output signal when the information receiving device converts the digital video information into an analog video signal and outputs the analog video signal to an external device. The information transmission method according to claim 15, wherein
The information transmission method according to claim 1, wherein the control information limits a resolution of an analog video signal output to the external device. An information output device for outputting input digital video information or digital video information reproduced from a storage medium to an external device,
A control information detection circuit for detecting control information added to the digital video information;
An output circuit for outputting the digital video information to the external device;
A state recognition circuit for recognizing the state of the external device or the output circuit;
An output control circuit for controlling the output of the output circuit,
The output control circuit controls the output circuit based on the control information detected by the control information detection circuit and the state of the external device or output circuit recognized by the state recognition circuit. Output device.   18. The information output apparatus according to claim 17, wherein the control information is information relating to copy restriction of the digital video information or protection of the video information.   When the state recognition circuit cannot recognize the state of the external device or the output circuit, and the control information specifies copy restriction of the digital video information or protection of the video information, the output control circuit The information output device according to claim 18, wherein output from the output circuit is stopped.   20. The recognition of the state of the external device or the output circuit by the state recognition circuit includes authentication using a key signal with the external device or the output circuit. The information output device according to item 1.   The output circuit includes a first output circuit that outputs the digital video information, and a second output circuit that converts the digital video information into an analog video signal and outputs the analog video signal. 20. The information output device according to any one of claims 17 to 19, wherein the output circuit includes the output circuit.   20. The output circuit has a function of protecting and outputting the digital video information, and the state of the output circuit includes whether the output is performed with protection. The information output device according to any one of the above. An information output method for outputting input digital video information or digital video information reproduced from a storage medium from a first device to a second device,
Detecting control information added to the digital video information;
Recognizing the state of the first device or the second device,
An information output method, comprising: controlling output from the first device based on the detected control information and the recognized state of the first device or the second device.   24. The information output method according to claim 23, wherein the control information is information related to copy restriction of the digital video information or protection of video information.   If the status of the first device or the second device cannot be recognized and the control information specifies the copy restriction of the digital video information or the protection of the video information, The information output method according to claim 24, wherein the output is stopped.   26. The information according to claim 23, wherein the step of recognizing the state includes authentication using a key signal with the first device or the second device. output method.   The output from the first device has a function of outputting the digital video information and a function of converting the digital video information into an analog video signal and outputting the analog video signal. 26. The information output method according to any one of claims 23 to 25, including whether the information is output.   The output from the first device has a function of outputting the digital video information with protection, and the state of the first device includes whether the output is performed with protection. 26. The information output method according to any one of claims 23 to 25, characterized in that: In an information transmission method for transmitting digital video information toward an information output device that inputs information and outputs the information to an external device,
To the digital video information to be transmitted, control information relating to copy restriction of the digital video information or protection of the video information is added,
The control information is combined with the result of recognizing the state of the information output device or the external device to control the output of the digital video information when the digital video information is output from the information output device to the external device. An information transmission method characterized by being used for the purpose.

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