JP3435277B2 - Copy protection device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to an apparatus such as a television receiver that handles information transmitted through any medium such as wire communication, wireless communication or recording medium, and is a chaotic copy of the information. The present invention relates to a copy protection device for preventing the above.

[0002]

2. Description of the Related Art A system for transmitting moving images and sounds such as television broadcasting, a video conference system and a videophone, and recording / reproducing signals such as moving images and sounds on a magnetic disk, an optical disk and a magnetic tape. In such a system, a method of performing high-efficiency coding and increasing transmission efficiency is generally used in order to effectively use a transmission line and a recording medium.

MPE is a typical method of this high efficiency coding.
There is G2 (Moving Picture Expert Group 2). MPE
G2 is ISO (International Organization for Sta)
ndardization) and IEC (International Electrotec
hnical Commision's JTC (Joint Technical Commit)
tee) standardized as ISO / IEC13818.

In MPEG2, not only the coding standard but also the standard is defined for the method of multiplexing the data stream of video and audio so that the coded data stream of video and audio can be used for a wide range of purposes. Has been. This standard is MPEG2 Systems
It is called a transport stream (TS: Transport Stream) intended for broadcasting and communication, and a program stream (PS: Progtam) intended for storage and recording depending on the usage of the data stream.
Stream)).

The transport stream is considered to transmit a plurality of programs in one stream, a plurality of reference times can be used for each program, and will be adopted in many broadcasting and communication applications in the future. Seen as a thing. Further, the program stream is expected to be adopted in many cases in the future as a standard recording format for storage media such as magnetic disks, optical disks and magnetic tapes. It should be noted that these standards are input signal standards to the decoder, and a signal encoding method is not specified.

When recording a program transmitted by digital broadcasting, digital communication, etc., the following procedure is performed. For example, the received digital broadcast wave is demodulated into a baseband transport stream. A plurality of programs are included in the demodulated output transport stream. A PES (Packetized) of a specific program is selected from the plurality of programs by a transport process.
Elementary Stream) is extracted. This PES is decoded and converted into Y, RY, and BY signals and reproduced as an image on a CRT. Also, each of the Y, RY, and BY signals is encoded to create an NTSC signal or S signal, which is recorded by a recording device such as a VTR (Video Tape Recorder). The recording device need not be a tape but may be a disk medium such as a hard disk or an optical disk.

The above is the case of analog recording, but digital recording can also be performed by the following procedure. The received digital broadcast wave is demodulated into a baseband transport stream. A plurality of programs are included in the demodulated output transport stream. A PES of a specific program is extracted from the plurality of programs by a transport process. And this extracted PES
Is converted into a program stream and recorded by a recording device such as a VTR or a disk medium.

The data read (reproduced) by the recording device is converted into a transport stream and then selectively subjected to a transport process with a reception output (demodulation output). As a result, the image is reproduced in the same manner as when it was received.

However, in the apparatus configured to record by the above configuration, the transmitted image and sound or the image and sound recorded on the recording medium are
It is possible to freely record on another recording medium. Therefore, images and sounds may be copied against the intention of the author. In particular, when the image and the sound are represented by digital data, the image and the sound are less deteriorated even if the copying is repeated, so that a large number of copies may be made.

[0010]

As described above, the prior art is as follows.
Since the transmitted information could be freely recorded on another recording medium, there was a problem that the information might be copied contrary to the intention of the author and distributed randomly. .

The present invention has been made in consideration of such circumstances, and an object thereof is to restrict disorderly copying of information users by the intention of the information supplier such as the author. It is to provide a copy protection device capable of performing the above.

[0012]

A copy protection apparatus according to the present invention is supplied with a digital signal having a copy flag indicating whether copying is permitted or not and permission of one copy is inputted, and a digital signal is supplied based on the copy flag. Copy permission / prohibition determining means for determining permission / prohibition of signal copying and permission for one-time copying, and a part of the digital signal.
The filter that extracts only the wavenumber component and the output of this filter
The output signal and the digital signal are judged by the copy approval / disapproval judgment means.
Switching means for selectively switching and outputting based on a fixed result
And a signal that makes it possible to reproduce predetermined information from the digital signal when the copy permission / inhibition determination means determines that copying is possible, and one copy is permitted by the copy permission / inhibition determination means. If it is determined that the signal that can reproduce the predetermined information from the digital signal
Output as a recording signal, if it is determined that it is impossible copy signals consisting of only a part of the frequency components of the digital signal was Unishi by you output as a recording signal to the copy permission determination unit It is a thing.

[0013]

[0014]

[0015]

[0016]

[0017]

According to the above-mentioned configuration, with respect to the digital signal whose copy flag indicates that copying is prohibited (copy prohibition), a part of the frequency components of the digital signal are not formed.
A signal consisting of only minutes is output from the digital signal processing device as a recording signal, and even if this recording signal is recorded,
Normal information cannot be reproduced from the recording signal.

[0019]

DETAILED DESCRIPTION OF THE INVENTION

(First Embodiment) A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a functional block diagram showing a main configuration of a television receiver to which the copy protection system according to this embodiment is applied. As shown in this figure, the television receiver of this embodiment includes an antenna 1, a demodulation circuit 2, a transport processing circuit 3, and M.
PEG decoder 4, adder circuit 5, switch 6, NTSC
It has an encoder 7 and an OSD signal generation circuit 8.

The antenna 1 receives an incoming broadcast wave,
This is converted into a high frequency electric signal. The antenna 1 gives the generated high frequency signal to the demodulation circuit 2. Demodulation circuit 2
Demodulates the baseband transport stream from the high frequency signal supplied from the antenna 1. The demodulation circuit 2 gives the demodulated transport stream to the transport processing circuit 3.

The transport processing circuit 3 is composed of, for example, a microprocessor, and performs transport processing for extracting a PES (Packetized Elemntary Stream) of a specific program from a plurality of programs included in the transport stream. The transport processing circuit 3 gives the extracted PES to the MPEG decoder 4. Further, the transport processing circuit 3 has a copy flag state detecting means 3a. The copy flag state detecting means 3a detects the states of the copy flags (copyright flag and original copy flag) included in the PES to be extracted, and outputs a detection result signal according to the state of the copy flags.

The MPEG decoder 4 decodes the PES supplied from the transport processing circuit 3 and outputs Y, R-
Converted to Y and BY signals. MPEG decoder 4
Supplies the generated Y, RY, and BY signals to the addition circuit 5 and also to the NTSC encoder 7 via the switch 6.

The adder circuit 5 outputs the signal supplied from the MPEG decoder 4 to the OS output from the OSD signal generation circuit 8.
After superimposing the D signal, it is output to the CRT. The switch 6 is turned ON / OFF according to the detection result signal output from the transport processing circuit 3, and when in the ON state, the output signal of the MPEG decoder 4 is sent to the NTSC encoder 7
Give to.

The NTSC encoder 7 produces an NTSC signal or an S signal from the output signal of the MPEG decoder 4,
This is output as a signal for VTR recording. The OSD signal generating circuit 8 has the same structure as a general one used for displaying a channel number or the like in an existing television receiver, but the detection result output from the transport processing circuit 3 is used. Based on the signal, an OSD (On Screen Display) signal for indicating an image indicating that copying is prohibited on the image being received is generated as necessary. The OSD signal generation circuit 8 gives the generated OSD signal to the addition circuit 5.

Next, the operation of the television receiver configured as described above will be described. The incoming digital broadcast wave is
The signal is received by the antenna 1 and demodulated by the demodulation circuit 2 into a baseband transport stream. Since the transport stream output from the demodulation circuit 2 includes a plurality of programs, the transport processing circuit 3 extracts the PES of a specific program. The extracted PES is converted into Y, RY and BY signals by the MPEG decoder 4 and sent to a CRT (not shown). Thus, in the CRT, the image is reproduced and displayed based on the Y, RY, and BY signals.

By the way, the transport stream, program stream and PES are all ISO /
Specified by IEC13818. Figure 2 shows this transport stream, program stream and PE.
It is a figure which shows the relationship of S, (a) shows a transport stream, (b) shows PES, (c) shows the structure of a program stream, respectively.

The transport stream is composed of 188-byte fixed-length packets including a 4-byte header. A plurality of programs are multiplexed in this transport stream, and constituent elements (video data, audio data, other digital data) of the programs are distributed to different packets. The PES is data in which a specific program in the transport stream is extracted and arranged. In the program stream, PES is multiplexed into an arbitrary unit size to form pack data (Packdata), and a pack header is added to the pack data. As described above, PES is defined as a stream used for conversion between the transport stream and the program stream.

FIG. 3 is a diagram showing in detail the format of the packet of the transport stream (in particular, the format of the header). As shown in this figure, the transport stream header consists of an 8-bit sync byte.
e) 1-bit error indication (transport error indicato)
r) 1-bit unit start indicator (payload unit sta
rt indicator) 1-bit priority (transpor
t priority), 13-bit PID (packet identific
ation), 2-bit scramble control (transport sc
rambling control), 2-bit adaptation field control, and 4-bit continuity counter. And the adaptation field (adaptati
On field) and payload are followed by a packet of the transport stream. The constituent elements of the program placed in the payload of the packet are indicated by the numerical values assigned to the PID.

FIG. 4 is a diagram showing in detail the format of the first 7 bytes of PES. PES as shown in this figure
Is the 24-bit packet start code
prefix), an 8-bit stream ID (stream id),
16-bit packet length (PES packet length), "1"
0 "2 fixed bits, 2 bit scrambling control (PES scrambling control), 1 bit priority (PES priority), 1 bit data alignment indicator (data allengiment indicator), 1 bit copyright flag (copylight) And a 1-bit original copy flag (original or copy) are set in order.

In the present embodiment, in the broadcasting station, the copyright flag is set to "1" for the program permitting copying, and the copyright flag is set to "0" for the program restricting copying.
Also, at the broadcasting station, when copying is restricted,
To completely prohibit copying, set the original copy flag to a state indicating "copy" (for example, "0"), or 1
When only one copy is permitted, the original copy flag is set to a state indicating "original" (for example, "1").

At the same time as the transport stream, the demodulation circuit 2 gives to the transport processing circuit 3 a header timing pulse as shown in FIG. 5 (b) which is synchronized with the beginning of the transport stream.

In addition to the above PES extraction processing, the transport processing circuit 3 uses the copy flag status detecting means 3a to detect the status of the copy flag by the header timing pulse as follows. To do. That is, as shown in FIG. 6, when the transport processing circuit 3 first detects the header timing pulse (step ST1), it reads 4-byte data from that point, that is, the header portion of the transport stream (step ST2). Next, the transport processing circuit 3 determines whether or not there is an adaptation field by identifying the adaptation control data in the fetched header (step ST3). If there is an adaptation field, the transport processing circuit 3 The part is skipped (step ST4).

If there is a PES after that, the transport processing circuit 3 reads the first 7 bytes (step S
T5). Then, the 7th byte has a copyright flag and an original copy flag. The transport processing circuit 3 detects the states of the copyright flag and the original copy flag (step ST6),
A detection result signal indicating the detection result is output (step ST7).

Now, when the detection result signal output from the transport processing circuit 3 indicates that copying is possible,
That is, when the copyright flag is "1" or the copyright flag is "0" but the original copy flag is "1" and the detection result signal indicates that, the switch 6 is turned on. It becomes a state. As a result, the output signal of the MPEG decoder 4 is given to the NTSC encoder 7. At this time, the NTSC encoder 7 receives the NTSC signal or S
A signal is created and this is output as a signal for VTR recording. Therefore, if a VTR of VHS system or the like is connected to receive the output of the NTSC encoder 7, recording can be performed by this VTR.

On the other hand, the transport processing circuit 3
When the detection result signal output by the above indicates that copying is not possible, that is, the copyright flag is "0" and the original copy flag is "0", and the detection result signal indicates that. At this time, the switch 6 is turned off. As a result, the output signal of the MPEG decoder 4 is not given to the NTSC encoder 7. Therefore, NT
In order to receive the output of the SC encoder 7, V such as VHS system
Even if TR is connected, a signal for recording is not output to this VTR, and recording cannot be performed.

At this time, the OSD signal generation circuit 8
An OSD signal for displaying an image indicating that copying of the image currently displayed on the CRT is prohibited on the CRT, such as “Cannot copy”, for example, as shown in FIG. 7A. To occur. This OSD signal is
It is superimposed on the output signal from the MPEG decoder circuit 4 by the adder circuit 5 and is displayed on the CRT as shown in FIG. 7A, for example.

In the OSD signal generation circuit 8, when the copy flag is "0" but the original copy flag is "1" and the detection result signal indicates that, that is, the recording is permitted only once. Even if
An OSD signal for displaying an image such as "This image can be copied up to once" on a CRT as shown in FIG. 7B may be generated.

According to the present embodiment as described above, a program for which copy prohibition is designated on the broadcast station side is not output as a VTR recording signal and cannot be recorded in the VTR. Therefore, it is surely prevented that the copying is performed randomly.

Further, in the present embodiment, since the program for which copy prohibition is designated is not output as a VTR recording signal, the user may feel anxiety that the device is malfunctioning or that the device is malfunctioning. Although it may be recognized, the above problem can be avoided because the CRT displays that copying is prohibited in this embodiment.

(Second Embodiment) Next, the second embodiment of the present invention will be described.
An embodiment will be described. FIG. 8 is a functional block diagram showing a main configuration of a television receiver to which the copy protection system according to this embodiment is applied. Note that FIG.
The same parts as those of the above are denoted by the same reference numerals, and detailed description thereof will be omitted.

As shown in this figure, the television receiver of this embodiment includes an antenna 1, a demodulation circuit 2, a transport processing circuit 3, an MPEG decoder 4, an addition circuit 5, and an NT.
SC encoder 7, OSD signal generation circuit 8, addition circuit 9, copy guard signal generation circuit 10 and switch 11
To have.

That is, in this embodiment, the output signal of the MPEG decoder 4 is given to the NTSC encoder 7 via the adder circuit 9 instead of the switch 6 in the first embodiment. Further, a copy guard signal generation circuit 10 and a switch 11 are added so that the output signal of the copy guard signal generation circuit 10 is given to the addition circuit 9 via the switch 11. Other configurations are the same as those in the first embodiment.

The adder circuit 9 outputs the output signal of the MPEG decoder 4 when the switch 11 is in the ON state and the output signal of the copy guard signal generation circuit 10 is given.
The output signal of the copy guard signal generation circuit 10 is superposed and given to the NTSC encoder 7.

The copy guard signal generation circuit 10 uses the MPE
In the vertical blanking period of the output signal of the G decoder 4, for example, a high brightness level and a low brightness level are set at predetermined intervals (for example, l
It generates a special signal (copy guard signal) such as alternate generation every second).

The switch 11 is turned on / off according to the detection result signal output from the transport processing circuit 3.
Then, the copy guard signal generated by the copy guard signal generating circuit 10 in the ON state is given to the adding circuit 9.

Next, the operation of the television receiver configured as described above will be described. First, the antenna 1, the demodulation circuit 2, the transport processing circuit 3, the MPEG decoder 4,
The adding circuit 5 and the OSD signal generating circuit 8 are the same as the first circuit described above.
It operates similarly to the embodiment.

Now, when the detection result signal output from the transport processing circuit 3 indicates that copying is possible,
That is, when the copyright flag is “1” or the copyright flag is “0” but the original copy flag is “1” and the detection result signal indicates that, the switch 11 is turned off. It becomes a state. As a result, the copy guard signal generated by the copy guard signal generation circuit 10 is blocked by the switch 11 and is not given to the addition circuit 9. At this time, the adder circuit 9 gives the output signal of the MPEG decoder 4 to the NTSC encoder 7 as it is. The NTSC encoder 7 creates an NTSC signal or an S signal from the given signal and outputs this as a signal for VTR recording. Therefore, NTSC encoder 7
If a VTR of the VHS system or the like is connected to receive the output of, the normal NTSC signal or S signal is given to this VTR, and normal recording can be performed.

On the other hand, the transport processing circuit 3
When the detection result signal output by the above indicates that copying is not possible, that is, the copyright flag is "0" and the original copy flag is "0", and the detection result signal indicates that. At this time, the switch 11 is turned on. As a result, the copy guard signal generated by the copy guard signal generation circuit 10 is given to the addition circuit 9 via the switch 11. At this time, the adder circuit 9
The output signal of the G decoder 4 is applied to the NTSC encoder 7 after superimposing the copy guard signal. The NTSC encoder 7 creates an NTSC signal or an S signal from the supplied signal and outputs it as a signal for VTR recording, and a copy guard signal is superimposed in the vertical blanking period of the signal. Therefore, even if a VTR of VHS system or the like is connected to receive the output of the NTSC encoder 7, the AGC (Auto Gain Control) circuit of this VTR malfunctions due to the copy guard signal, and the recorded image is Image quality is significantly degraded. It should be noted that the image recorded on the VTR in this manner is difficult to see because the screen brightness level changes each time dubbing is repeated.

According to the present embodiment as described above, for a program for which copy prohibition is designated on the broadcast station side, a copy guard signal is superimposed and output during the vertical blanking period of the VTR recording signal. Therefore, the VTR can record only an image whose image quality is significantly deteriorated. Therefore, it is surely prevented that the copying is performed randomly.

Further, in this embodiment, since an abnormal signal is output as a VTR recording signal for a program for which copy prohibition is designated, the user feels anxiety that the device is malfunctioning or the device malfunctions. However, even in the present embodiment, since the fact that copying is prohibited is displayed on the CRT, the above problem can be avoided.

(Third Embodiment) Next, the third embodiment of the present invention will be described.
An embodiment will be described. FIG. 9 is a functional block diagram showing a main configuration of a television receiver to which the copy protection system according to this embodiment is applied. Note that FIG.
The same parts as those in FIG. 8 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in this figure, the television receiver of this embodiment has an antenna 1, a demodulation circuit 2, a transport processing circuit 3, an MPEG decoder 4, an addition circuit 5, and an NT.
It has an SC encoder 7, an OSD signal generation circuit 8, an addition circuit 9, a switch 11 and an OSD signal generation circuit 12.

That is, in this embodiment, an OS is used instead of the copy guard signal generation circuit 10 in the second embodiment.
The D signal generating circuit 12 is provided. Other configurations are similar to those of the second embodiment.

The OSD signal generating circuit 12 has the same structure as a general one used for displaying a channel number and the like in an existing television receiver, but it is a copyright holder or broadcasting right of an image. An OSD (On Screen Display) signal for displaying an image showing the person on the recorded image is generated. The OSD signal generation circuit 12 uses the generated OS
The D signal is given to the adder circuit 9.

Next, the operation of the television receiver configured as described above will be described. First, the antenna 1, the demodulation circuit 2, the transport processing circuit 3, the MPEG decoder 4,
The adding circuit 5 and the OSD signal generating circuit 8 are the same as the first circuit described above.
It operates similarly to the embodiment.

Now, when the detection result signal output from the transport processing circuit 3 indicates that copying is possible,
That is, when the copyright flag is “1” or the copyright flag is “0” but the original copy flag is “1” and the detection result signal indicates that, the switch 11 is turned off. It becomes a state. As a result, the OSD signal generated by the OSD signal generating circuit 12 is blocked by the switch 11 and is not given to the adding circuit 9. At this time, the adder circuit 9 gives the output signal of the MPEG decoder 4 to the NTSC encoder 7 as it is. N
The TSC encoder 7 creates an NTSC signal or an S signal from the supplied signal and outputs this as a VTR recording signal. Therefore, if a VTR of VHS type or the like is connected to receive the output of the NTSC encoder 7, a normal NTSC signal or S signal is given to this VTR, and normal recording can be performed.

On the other hand, the transport processing circuit 3
When the detection result signal output by the above indicates that copying is not possible, that is, the copyright flag is "0" and the original copy flag is "0", and the detection result signal indicates that. At this time, the switch 11 is turned on. As a result, the OSD signal generated by the OSD signal generation circuit 12 is given to the addition circuit 9 via the switch 11. At this time, the adder circuit 9 causes the MPEG decoder 4
Is applied to the NTSC encoder 7 after superimposing the OSD signal. The NTSC encoder 7 creates an NTSC signal or an S signal from the supplied signal and outputs it as V
It is output as a signal for TR recording, and the image indicated by the signal is combined with the image indicating the copyright holder or the broadcasting right holder of the image. Therefore, in order to receive the output of the NTSC encoder 7, a VTR such as VHS system is connected,
Even if the VTR is used for recording, an image showing the copyright holder or the broadcasting right holder is combined with the recorded image.

According to the present embodiment as described above, the program for which the prohibition of copying is designated on the broadcast station side corresponds to the image indicating the copyright holder or the broadcasting right holder of the image in the signal for VTR recording. Since the OSD signal that is output is combined and output, the VTR can record only an image in which an image indicating the copyright holder or the broadcasting right holder is combined. Therefore, it is possible to make it clear that a person who does not have the distribution right has distributed the work or the broadcasted material of the person who has the distribution right in a disorderly manner, and it is possible to prevent the disorderly copying.

Further, in the present embodiment, as for the program for which copy prohibition is designated, a signal corresponding to an image in which an image unnecessary for the user is combined is output as a VTR recording signal, so that a user who does not understand the situation However, even in the present embodiment, since the fact that copying is prohibited is displayed on the CRT, the above-mentioned problem can be avoided.

(Fourth Embodiment) Next, the fourth embodiment of the present invention will be described.
An embodiment will be described. FIG. 10 is a functional block diagram showing a main configuration of a television receiver to which the copy protection system according to this embodiment is applied. The same parts as those in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in this figure, the television receiver of this embodiment has an antenna 1, a demodulation circuit 2, a transport processing circuit 3, an MPEG decoder 4, an addition circuit 5 and an NT.
It has an SC encoder 7, an OSD signal generation circuit 8, a selection switch 13 and a low pass filter (LPF).

That is, in this embodiment, the output signal of the MPEG decoder 4 is applied to the NTSC encoder 7 via the selection switch 13 instead of the switch 6 in the first embodiment. In addition, the selection switch 13
By switching the output signal of the MPEG decoder 4 to L
It can be applied to the NTSC encoder 7 via the PF 14 and the selection switch 13. Other configurations are the same as those in the first embodiment.

The selection switch 13 is switched according to the detection result signal output from the transport processing circuit 3,
The output signal of the MPEG decoder 4 is directly or LP
It is given to the NTSC encoder 7 via F14.

The LPF 14 extracts only the low frequency component of the output signal of the MPEG decoder 4 and outputs it. Next, the operation of the television receiver configured as described above will be described. First, the antenna 1, the demodulation circuit 2, the transport processing circuit 3, the MPEG decoder 4, the addition circuit 5 and the OSD signal generation circuit 8 operate in the same manner as in the first embodiment.

Now, when the detection result signal output from the transport processing circuit 3 indicates that copying is possible,
That is, when the copyright flag is “1” or the copyright flag is “0” but the original copy flag is “1” and the detection result signal indicates that, the selection switch 13 The output signal of the MPEG decoder 4 is directly applied to the NTSC encoder 7. At this time, the NTSC encoder 7 uses the MPEG
An NTSC signal or an S signal is created from the output signal of the decoder 4, and this is output as a VTR recording signal. Therefore, if a VTR of VHS type or the like is connected to receive the output of the NTSC encoder 7, a normal NTSC signal or S signal is given to this VTR, and normal recording can be performed.

On the other hand, the transport processing circuit 3
When the detection result signal output by the above indicates that copying is not possible, that is, the copyright flag is "0" and the original copy flag is "0", and the detection result signal indicates that. When the selection switch 13 is LP
The output of F14 is selected. This allows LP
Only the low frequency component of the output signal of the MPEG decoder 4 extracted in F14 is given to the NTSC encoder 7. The NTSC encoder 7 creates an NTSC signal or an S signal from the supplied signal and outputs this as a signal for VTR recording, which signal is generated from only the low frequency component of the output signal of the MPEG decoder 4. Therefore, it has only a small part of the information for representing the original image. Therefore, even if a VTR of VHS system or the like is connected to receive the output of the NTSC encoder 7, the image quality of the image recorded by this VTR is significantly deteriorated.

According to the present embodiment as described above, for the program for which the prohibition of copying is designated on the broadcast station side, only the low frequency component of the output signal of the MPEG decoder 4 is used as the VTR recording signal. Since the signal generated from the VTR is output, the VTR can record only an image whose image quality is significantly deteriorated. Therefore, it is surely prevented that the copying is performed randomly.

Further, in this embodiment, since an abnormal signal is output as a VTR recording signal for a program for which copy prohibition is designated, the user may feel anxiety that the device is malfunctioning or the device malfunctions. However, even in the present embodiment, since the fact that copying is prohibited is displayed on the CRT, the above problem can be avoided.

(Fifth Embodiment) In each of the above-described embodiments, the output for VTR recording is changed to NTSC signal or S.
Although a television receiver corresponding to analog recording by a VHS system VTR or the like is used as an analog signal such as a signal, the present invention is also applied to a television receiver corresponding to digital recording by a digital VTR or an optical disk. It is possible.

A fifth embodiment of the present invention in which the copy protection system of the present invention is applied to a television receiver compatible with digital recording as described above will be described below.

FIG. 11 is a functional block diagram showing the main structure of the television receiver according to this embodiment. The same parts as those in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in this figure, the television receiver of this embodiment includes an antenna 1, a demodulation circuit 2, a transport processing circuit 3, an MPEG decoder 4, an addition circuit 5, and an OS.
It has a D signal generation circuit 8 and a signal correction circuit 15.

That is, in this embodiment, the switch 6 and the NTSC encoder 7 in the first embodiment described above are eliminated, and the PES output from the transport processing circuit 3 is output as a signal for VTR recording via the signal correction circuit 15. I am trying to do it. Other configurations are the same as those in the first embodiment.

The signal correction circuit 15 changes its operation state according to the detection result signal output from the transport processing circuit 3, and implements or disconnects the output of the PES. Next, the operation of the television receiver configured as described above will be described. First, the antenna 1, the demodulation circuit 2, the transport processing circuit 3, the MPEG decoder 4, the addition circuit 5 and the OS
The D signal generation circuit 8 operates in the same manner as in the first embodiment described above.

In this state, the signal correction circuit 15 performs the processing as shown in FIG. That is, the signal correction circuit 1
5 first takes in the detection result signal output from the transport processing circuit 3 (step ST11), and judges based on this signal whether or not copying is possible (step ST12).

Here, when the detection result signal output from the transport processing circuit 3 indicates that copying is possible, that is, whether the copyright flag is "1",
Alternatively, when the copyright flag is “0” but the original copy flag is “1” and the detection result signal indicates that, the signal correction circuit 15 performs PES output (step ST13). As a result, PES becomes VT
It is output as a signal for R recording. Therefore, in order to receive the PES output from the signal correction circuit 15, the digital VTR
Can be recorded on this digital VTR.

On the other hand, the transport processing circuit 3
When the detection result signal output by the above indicates that copying is not possible, that is, the copyright flag is "0" and the original copy flag is "0", and the detection result signal indicates that. When the signal correction circuit 15 is PE
The S output is disconnected (step ST14). This allows
PES is not output as a signal for VTR recording. Therefore, even if a digital VTR is connected to receive the PES output from the signal correction circuit 15, a recording signal is not output to the digital VTR and recording cannot be performed.

According to the present embodiment as described above, for a program for which copy prohibition is designated on the broadcast station side, PES is not output as a signal for VTR recording, and recording on a digital VTR is performed. I can't. Therefore, it is surely prevented that the copying is performed randomly.

Further, in the present embodiment, since PES is not output as a signal for VTR recording for a program for which copy prohibition is designated, the user feels anxiety that the device is malfunctioning or the device is malfunctioning. However, even in the present embodiment, the fact that copying is prohibited is displayed on the CRT, so that the above problem can be avoided.

(Sixth Embodiment) Next, a sixth embodiment of the present invention to which the copy protection system of the present invention is applied will be described.

FIG. 13 is a functional block diagram showing the main configuration of the television receiver according to this embodiment. The same parts as those in FIGS. 1 and 11 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in this figure, the television receiver of this embodiment has an antenna 1, a demodulation circuit 2, a transport processing circuit 3, an MPEG decoder 4, an addition circuit 5, and an OS.
D signal generation circuit 8, signal correction circuit 15 and PES / P
It has an S conversion circuit 16.

That is, in the present embodiment, the PES / PS conversion circuit 16 is interposed between the transport processing circuit 3 and the signal correction circuit 15 in the above-mentioned fifth embodiment. Other configurations are similar to those of the fifth embodiment.

The PES / PS conversion circuit 16 converts the PES output from the transport processing circuit 3 into a program stream. The PES / PS conversion circuit 16 gives the generated program stream to the signal correction circuit 15.

Thus, according to this embodiment, the fifth
The same effect as that of the embodiment can be achieved. (Seventh Embodiment) Next, a seventh embodiment of the present invention to which the copy protection system of the present invention is applied will be described.

FIG. 14 is a functional block diagram showing the main structure of the television receiver according to this embodiment. The same parts as those in FIGS. 1, 11 and 13 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in this figure, the television receiver of this embodiment has an antenna 1, a demodulation circuit 2, a transport processing circuit 3, an MPEG decoder 4, an addition circuit 5, and an OS.
D signal generation circuit 8, signal correction circuit 15 and PES / P
It has an S conversion circuit 16.

That is, in this embodiment, the order of the signal correction circuit 15 and the PES / PS conversion circuit 16 in the above-described sixth embodiment is reversed. Other configurations are similar to those of the sixth embodiment.

With this configuration, in the present embodiment, V
A signal for TR recording is output in the form of a program stream. Note that this program stream output /
The disconnection is performed by performing / disconnecting the PES output to the PES / PS conversion circuit 16 by the signal correction circuit 15 in the same manner as in the above-described fifth embodiment.

Thus, according to this embodiment, the sixth
The same effect as that of the embodiment can be achieved. (Eighth Embodiment) By the way, in each of the above embodiments, when the copyright flag is "0" but the original copy flag is "1", that is, when the copy is permitted only once. , VTR recording signals are output. Therefore, if the signal recorded by the VTR is input to the transport processing circuit 3 again, it can be stored in another recording medium, and copying (dubbing) is performed. Therefore, an eighth embodiment of the present invention that assumes such copying will be described below.

FIG. 15 is a functional block diagram showing the main structure of the television receiver according to this embodiment. The same parts as those in FIGS. 1, 11 and 13 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in this figure, the television receiver of this embodiment has an antenna 1, a demodulation circuit 2, a transport processing circuit 3, an MPEG decoder 4, an addition circuit 5, and an OS.
It has a D signal generation circuit 8, a PES / PS conversion circuit 16, a signal correction circuit 17, a PS / TS conversion circuit 18, and an input selector 19.

That is, in this embodiment, a signal correction circuit 17 is provided instead of the signal correction circuit 15 in the sixth embodiment described above. Also, a digital VTR (not shown)
A PS / TS conversion circuit 18 for receiving the program stream reproduced from the recording medium M by the above is provided. Further, an input selector 19 is provided between the demodulation circuit 2 and the transport processing circuit 3.

The signal correction circuit 17 operates almost similarly to the signal processing circuit 15, except that it has a function of rewriting the original copy flag as needed.

The PS / TS conversion circuit 18 receives the program stream reproduced from the recording medium M by a digital VTR (not shown) or the like and converts it into a transport stream. The PS / TS conversion circuit 18 gives the generated transport stream to the input selector 19.

The input selector 19 includes the transport stream output from the demodulation circuit 2 and the PS / TS conversion circuit 18.
And the transport stream output by the transport processing circuit 3 by selecting one of them.
Give to.

Next, the operation of the television receiver configured as described above will be described. First, when the input selector 19 is selecting the output of the demodulation circuit 2, the antenna 1, the demodulation circuit 2, the transport processing circuit 3, the MPEG decoder 4, the addition circuit 5 and the OSD signal generation circuit 8 have the above-mentioned first It operates similarly to the embodiment.

When the input selector 19 selects the output of the PS / TS conversion circuit 18, the transport stream obtained by converting the program stream read from the recording medium M by the PS / TS conversion circuit 18 is obtained. Are provided to the transport processing circuit 3. Also at this time, the transport processing circuit 3, the MPEG decoder 4,
The adder circuit 5 and the OSD signal generation circuit 8 operate in the same manner as the above-described first embodiment. Therefore, the image recorded on the recording medium is reproduced.

In this state, the signal correction circuit 17 performs the processing shown in FIG. That is, the signal correction circuit 1
7 first takes in the detection result signal output from the transport processing circuit 3 (step ST21), and based on this signal, determines whether or not copying is possible (step ST22).

Here, when the detection result signal output from the transport processing circuit 3 indicates that copying is possible, that is, whether the copyright flag is "1",
Alternatively, when the copyright flag is “0” but the original copy flag is “1” and the detection result signal indicates that, the signal correction circuit 17 subsequently determines whether or not unlimited copying is possible. Make a decision (step ST2)
3).

If the copyright flag is "1", unlimited copying is permitted, and the signal correction circuit 17 outputs the program stream as it is (step ST24). As a result, the program stream is output as a signal for VTR recording. Therefore, if the digital VTR is connected to receive the program stream output from the signal correction circuit 17, the program stream can be recorded on the recording medium M by the digital VTR. That is, if the input selector 19 selects the demodulation circuit 19, the received image is recorded on the recording medium, and the input selector 19 outputs P
If the S / TS conversion circuit 18 is selected, the image read from the recording medium M will be dubbed onto another recording medium M.

On the other hand, the copyright flag is "0".
However, when the original copy flag is "1", copying is permitted only once, and unlimited copying is not permitted. Therefore, the signal correction circuit 17
Is "0" indicating the copy status of the original copy flag
To the program stream (step ST2).
4). As a result, the program stream is output as a signal for VTR recording. Therefore, the signal correction circuit 17
If a digital VTR is connected to receive the output of the program stream from, the program stream can be recorded on the recording medium M by the digital VTR. That is, if the input selector 19 selects the demodulation circuit 19, the received image is recorded on the recording medium, and the input selector 19 causes the PS / TS conversion circuit 18 to be recorded.
If is selected, the image read from the recording medium M is dubbed on another recording medium M. However, in the program stream recorded on the recording medium M, both the copyright flag and the original copy flag are set to "0".

Now, when the detection result signal output from the transport processing circuit 3 indicates that copying is impossible,
That is, when the copyright flag is "0", the original copy flag is "0", and the detection result signal indicates that, the signal correction circuit 17 disconnects the program stream output (step ST26). As a result, the program stream is not output as a signal for VTR recording. Therefore, even if a digital VTR is connected to receive the program stream output from the signal correction circuit 17, the recording signal is not output to the digital VTR, and the program stream can be recorded on the recording medium M. Can not.

At this time, when the information which has already been copied by allowing only one copy is read from the recording medium M for dubbing, the copyright flag and the original copy flag of this information are as described above. Since both of them are set to "0", the signal correction circuit 17 cuts off the program stream output, and the program stream cannot be recorded on the recording medium M, that is, dubbing cannot be performed.

According to the present embodiment as described above, for a program for which copy prohibition is designated on the broadcast station side, the program stream is not output as a signal for VTR recording, and the recording medium M is used by the digital VTR. Cannot be recorded. Therefore, it is surely prevented that the copying is performed randomly.

Further, according to the present embodiment, when the information which is permitted to be copied only once is output as the signal for VTR recording, the original copy flag is rewritten to "0" indicating the copy state. When reproducing, the program stream is not output as a signal for VTR recording, and recording on the recording medium M cannot be performed by the digital VTR. Therefore, it is possible to reliably allow only one copy and prevent chaotic dubbing.

Further, in this embodiment, since the program stream is not output as a signal for VTR recording for the program for which copy prohibition is designated, the user may feel anxiety that the device is malfunctioning or that the device malfunctions. Although it may be recognized that there is such a problem, even in the present embodiment, the fact that copying is prohibited is displayed on the CRT, so that the above-mentioned problem can be avoided.

The present invention is not limited to the above embodiments. For example, in each of the above-described embodiments, the OSD signal is used to display the copy restriction on the display screen of the CRT. However, similar display is performed on the display panel used for displaying the channel number being received. You may display. This can be achieved by controlling the display content as long as the display panel can set the display content like a liquid crystal panel. Alternatively, as shown in FIG. 17, LED display devices 20a and 20b are provided, and a circuit for driving the LED display devices 20a and 20b is provided, and LED display is performed according to the state of the detection result signal output from the transport processing circuit 3. The lighting states of the containers 20a and 20b may be changed.

Further, in each of the above-described embodiments, the display regarding the copy restriction is displayed, but this is not essential and may not be displayed. Further, in each of the above-described embodiments, the copy protection system according to the present invention is applied to a television receiver for receiving television broadcasting, but it is recorded on various media such as a magnetic tape, a magnetic disk or an optical disk. The present invention can be applied to any system that distributes information on an arbitrary medium such as an information reproducing apparatus and reproduces information from the medium.

In the third embodiment, the OSD signal generating circuits 8 and 12 may be shared by one. In addition, in the fifth to eighth embodiments, the signal correction circuit 1
Nos. 5 and 17 stop outputting the signal for VTR recording when copying is impossible, but by performing arbitrary data processing, processing similar to that of the second to fourth embodiments can be performed. It is also possible to do. Alternatively, data of a certain fixed period is fixed to one of 0 and 1.
You may perform what is called a stuffing. In addition, various modifications can be made without departing from the scope of the present invention.

[0111]

According to the present invention, the information such as the author is provided.
Chaotic copy by users of information, depending on the will of the payer
Can be restricted.

[0112]

[Brief description of drawings]

FIG. 1 is a functional block diagram showing a main configuration of a television receiver to which a copy protection system according to a first embodiment of the present invention is applied.

FIG. 2 is a diagram showing a relationship between a transport stream, a program stream and a PES.

FIG. 3 is a diagram showing in detail a packet format (particularly a header format) of a transport stream.

FIG. 4 is a diagram showing in detail the format of the first 7 bytes of PES.

FIG. 5 is a diagram showing a header timing pulse output from a demodulation circuit 2.

6 is a flowchart showing a processing procedure of the transport processing circuit 3 shown in FIG.

FIG. 7 is a diagram showing a display example of a copy restriction state.

FIG. 8 is a functional block diagram showing a main configuration of a television receiver to which a copy protection system according to a second embodiment of the present invention is applied.

FIG. 9 is a functional block diagram showing a main configuration of a television receiver to which a copy protection system according to a third embodiment of the present invention is applied.

FIG. 10 is a functional block diagram showing a main configuration of a television receiver to which a copy protection system according to a fourth embodiment of the present invention is applied.

FIG. 11 is a functional block diagram showing the main configuration of a television receiver to which the copy protection system according to the fifth embodiment of the present invention is applied.

12 is a flowchart showing a processing procedure of the signal correction circuit 15 shown in FIG.

FIG. 13 is a functional block diagram showing a main configuration of a television receiver to which a copy protection system according to a sixth embodiment of the present invention is applied.

FIG. 14 is a functional block diagram showing a main configuration of a television receiver to which a copy protection system according to a seventh embodiment of the present invention is applied.

FIG. 15 is a functional block diagram showing the main configuration of a television receiver to which the copy protection system according to the eighth embodiment of the present invention is applied.

16 is a flowchart showing a processing procedure of the signal correction circuit 17 shown in FIG.

FIG. 17 is a diagram showing a modification of the display of the copy restriction status.

[Explanation of symbols]

1 ... antenna 2 ... Demodulation circuit 3 ... Transport processing circuit 3a ... Copy flag state detecting means 4 ... MPEG decoder 5, 9 ... Adder circuit 6, 11… Switch 7 ... NTSC encoder 8, 12 ... OSD signal generation circuit 10 ... Copy guard signal generation circuit 13 ... Selection switch 14 ... Low-pass filter (LPF) 15, 17 ... Signal correction circuit 16 ... PES / PS conversion circuit 18 ... PS / TS conversion circuit 19 ... Input selector

Front page continuation (72) Inventor Atsushi Hirota 8 Shinsugita-cho, Isogo-ku, Yokohama, Kanagawa Prefecture, Toshiba Multimedia Technology Laboratory Co., Ltd. (56) Reference JP-A-7-230668 (JP, A) JP-A-5 -30466 (JP, A) JP 7-235131 (JP, A) JP 5-37898 (JP, A) JP 8-265723 (JP, A) JP 6-54289 (JP, A) ) JP-A-5-347744 (JP, A) JP-A-6-124539 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04N 5/91-5 / 956,7 / 173

Claims (4)

(57) [Claims] 1. A digital signal having a copy flag in which permission / inhibition of copying and permission of one-time copying are arbitrarily indicated is input, and permission / inhibition of copying of the digital signal and one-time copying are performed based on the copy flag. Copy permission / inhibition determination means for determining permission and only a part of frequency components of the digital signal are extracted.
A filter for output, and the digital signal and the output signal of the filter, before
Selective switching based on the judgment result of the copy permission judgment means.
Switching means for switching and outputting, and a signal that makes it possible to reproduce predetermined information from the digital signal when the copy possibility determining means determines that the copy is possible, and the copy possibility determining means. it is not copied by said signals forming a reproducible predetermined information from the digital signal and outputs as a recording signal, before Symbol copy determination means when one copy is judged as being permitted by you output a signal consisting of only a part of frequency components of said digital signal as a recording signal when it is determined that
Copy protection device comprising a call. 2. When the copy permission / inhibition determination means determines that one copy is permitted, a notification means is provided to notify the user that the copy is limited to only once. The copy protection device according to claim 1, which is characterized in that. Wherein the copy flag is claim 1 or claim, characterized in that a copy of availability and one copy of the authorization using a copyright flag and original copy flag is respectively shown in any The copy protection device described in 2. 4. A notification means for notifying a user that copying is prohibited when the copy permission / inhibition determination means determines that copying is impossible. Item 4. The copy protection device according to any one of items 3.