U.S. patent application number 09/820957 was filed with the patent office on 2001-08-02 for information signal output control method, information signal duplication prevention method, information signal duplication prevention device, and information signal recording medium.
This patent application is currently assigned to Sony Corporation. Invention is credited to Ogino, Akira.
Application Number | 20010010756 09/820957 |
Document ID | / |
Family ID | 11743970 |
Filed Date | 2001-08-02 |
United States Patent
Application |
20010010756 |
Kind Code |
A1 |
Ogino, Akira |
August 2, 2001 |
Information signal output control method, information signal
duplication prevention method, information signal duplication
prevention device, and information signal recording medium
Abstract
If only any one of a pair of an SS anti-duplication control
signal S5 and copy guard signal S6 generated correlatively each
other added on the video signal played back from the disk is
detected, or if the specific anti-duplication control signal is not
detected, the video signal recorded in the disk is judged to be an
illegally duplicated video signal, and the output control signal
generation section controls the output control section so as not to
output the playback video signal S4.
Inventors: |
Ogino, Akira; (Chiba,
JP) |
Correspondence
Address: |
Jay H. Maioli
Cooper & Dunham
1185 Avenue of the Americas
New York
NY
10036
US
|
Assignee: |
Sony Corporation
|
Family ID: |
11743970 |
Appl. No.: |
09/820957 |
Filed: |
March 30, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
09820957 |
Mar 30, 2001 |
|
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|
09007186 |
Jan 15, 1998 |
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Current U.S.
Class: |
386/257 ; 360/60;
380/203; 386/256; 386/E5.004; G9B/20.002 |
Current CPC
Class: |
G11B 20/00768 20130101;
H04N 2005/91328 20130101; H04N 2005/91371 20130101; G11B 20/00913
20130101; H04N 2005/9135 20130101; H04N 2005/91321 20130101; H04N
5/913 20130101; G11B 20/00086 20130101 |
Class at
Publication: |
386/94 ; 380/203;
360/60 |
International
Class: |
H04N 005/76; H04N
005/91; H04N 007/167; G11B 015/04; G11B 019/04 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 23, 1997 |
JP |
P09-010212 |
Claims
What is claimed is:
1. An information signal output control method, a plurality of
anti-duplication control signals of different types generated
correlatively each other added on said information signal being
detected, and output control of said information signal being
performed dependently on detection condition of said plurality of
anti-duplication control signals of different types.
2. An information signal output control method as claimed in claim
1, wherein notice information is outputted if a specific
anti-duplication control signal out of said plurality of
anti-duplication control signals of different types generated
correlatively each other added on said information signal is missed
and playback output of said information signal is not
outputted.
3. An information signal output control method as claimed in claim
1, wherein one of said plurality of anti-duplication control
signals of different types generated correlatively each other is a
spectrally spread anti-duplication control signal superimposed on
said information signal.
4. An information signal duplication prevention method in which
when an information signal is duplicated, said information signal
on which a plurality of anti-duplication control signals of
different types generated correlatively each other is added is
duplicated.
5. An information signal duplication prevention method as claimed
in claim 4, wherein one of said plurality of anti-duplication
control signals of different types generated correlatively each
other is a spectrally spread anti-duplication control signal
superimposed on said information signal.
6. An information signal duplication prevention method as claimed
in claim 4, wherein when said plurality of anti-duplication control
signals of different types added on said information signal is
detected, at least any one of said plurality of anti-duplication
control signals of different types added on said information signal
is missed, a notice information is outputted.
7. An information signal output device comprising: anti-duplication
control signal detection means for detecting a plurality of
anti-duplication control signals of different types generated
correlatively each other added on the information signal, and
control means for performing output control of said information
signal dependently on detection condition of said plurality of
anti-duplication control signals of different types in said
anti-duplication control signal detection means.
8. An information signal output device as claimed in claim 7,
wherein said information signal output device is provided with a
notice information generation means, and if a detection result of
said anti-duplication control signal detection means indicates that
a specific anti-duplication control signal out of said plurality of
anti-duplication control signals of different types is missed and
playback output of said information signal is controlled so as not
to be outputted in compliance with control performed by means of
said control means, a notice information generated by means of said
notice information generation means is outputted.
9. An information signal output device as claimed in claim 7,
wherein one of said plurality of anti-duplication control signals
of different types generated correlatively each other is a
spectrally spread anti-duplication control signal added on said
information signal.
10. An information signal recording device comprising: first
anti-duplication control signal generation means for generating an
anti-duplication control signal, second anti-duplication control
signal generation means for generating one or more anti-duplication
control signals of different types correlatively generated with the
first anti-duplication control signal generated by said first
anti-duplication control signal generation means, and recording
means for recording an information signal on which said first
anti-duplication control signal generated by said first
anti-duplication control signal generation means and the second
anti-duplication control signal generated by said second
anti-duplication control signal are added in a recording
medium.
11. An information signal recording device as claimed in claim 10,
wherein said information signal recording device is provided with;
anti-duplication control signal detection means for detecting the
plurality of anti-duplication control signals of different types
added on an information signal, and recording control means for
performing recording control of said information signal based on
said anti-duplication control signal detected by said
anti-duplication control signal detection means.
12. An information signal recording device as claimed in claim 11,
wherein said information signal recording device is provided with a
notice information generation means, and if a detection result of
said anti-duplication control signal detection means indicates that
a specific anti-duplication control signal out of said plurality of
anti-duplication control signals of different types is missed and
said information signal is not outputted, a notice information
generated by means of said notice information generation means is
outputted.
13. An information signal recording device as claimed in claim 10,
wherein one of the plurality of anti-duplication control signals
added on said information signal recorded in said recording medium
by said recording means is a spectrally spread anti-duplication
control signal.
14. An information signal recording medium in which an information
signal containing a plurality of anti-duplication control signals
of different types generated correlatively each other added thereon
is recorded.
15. An information signal recording medium as claimed in claim 14,
wherein one of the plurality of anti-duplication control signals
added on said information signal recorded in said recording medium
by said recording means is a spectrally spread anti-duplication
control signal.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to a method, device, and recording
medium for output control and duplication prevention control using,
for example, an anti-duplication control signal recorded in a
recording medium together with an information signal.
[0003] 2. Description of Related Art
[0004] VTR (Video Tape recording devices) has been popularized in
daily life, and many kinds of software which can be played back on
a VTR are supplied abundantly. Digital VTR or DVD (Digital Video
Disks) playback devices have been available commercially now, and
provide images and sound of exceptionally high quality.
[0005] On the other hand, there is, however, a problem in that
software applications of this great abundance can be copied without
restriction, and several methods have already been proposed to
inhibit duplication.
[0006] For example, though the method is a method which inhibits
duplication of an analog video signal not directly, one method to
prevent copying uses a difference in the AGC (Automatic Gain
Control) system, or in the APC (Automatic Phase Control) system,
for example, between the VTR recording device and a monitor
receiver for displaying the image.
[0007] For example, the method which utilizes the difference in AGC
system, in which a VTR performs AGC using a pseudo sync signal
inserted in the video signal and a monitor receiver employs a
different AGC system not using the pseudo sync signal, is an
example of the former, in detail, when an analog video signal is
recorded in an original recording medium, a very high level pseudo
sync signal is previously inserted as a sync signal for AGC, and
the very high level pseudo sync signal is inserted in the video
signal to be supplied from a playback VTR to a recording VTR as a
sync signal for AGC.
[0008] Alternately, the method which utilizes the difference of APC
characteristics between a VTR and receiver as in the case that APC
in a VTR can follows the color burst signal in a video signal with
a short time constant but APC in a receiver follows with a
relatively long time constant is an example of the latter, in
detail, the phase of the color burst signal of a video signal is
previously inverted partially when the analog video signal is
recorded in an original recording medium, and the color burst
signal having partially inverted phase is outputted as a video
signal to be supplied from a playback VTR to a recording VTR.
[0009] As the result, the monitor receiver which receives the
analog video signal from the playback VTR plays back the image
correctly without being affected by the pseudo sync signal in AGC
or without desired affection of the partial phase inversion of the
color burst signal used for APC.
[0010] On the other hand, in a VTR, which is supplied with the
analog video signal from the playback VTR into which pseudo sync
signals have been inserted or which has been subjected to color
burst signal phase inversion control as described herein above, for
receiving such analog video signal and for recording the analog
video signal in a recording medium, proper gain control or phase
control based on the input signal cannot be performed, and so the
video signal is not correctly recorded. Even if this signal is
played back, therefore, normal picture and sound cannot be
obtained.
[0011] As described herein above, in the case that involves an
analog video signal, the prevention is not a method for directly
inhibiting duplication but is a method for viewing an abnormally
played back picture which can not viewed normally. Such prevention
method is a passive duplication prevention control.
[0012] On the other hand, in the case that a digitized information,
for example, video signal is involved, an anti-duplication signal
or an anti-duplication control signal comprising, for example, a
duplication ranking control code, is added as digital data to the
video signal and recorded on the recording medium, so as to prevent
or control duplication of the image.
[0013] FIG. 1 is a basic structural diagram of a duplication
apparatus for duplicating digitized information, a digital
information played back by the digital playback device 110 is sent
to a digital recording device 120 through a digital transmission
line 101, and the digital recording device 101 duplicates the
digital information if duplication is permitted and does not
duplicate the digital information if duplication is not
permitted.
[0014] An anti-duplication control information in the form of
additional information is recorded in a recording medium 111 placed
on the digital playback device 110 in addition to a digital main
information. The anti-duplication control information indicates
control content such as duplication inhibition, duplication
permission, or generation restriction. The digital playback section
113 reads out the information from the recording medium 111,
acquires the anti-duplication control information together with the
digital main information, and sends them to the digital recording
medium 120 through the digital transmission line 101.
[0015] An anti-duplication control signal detection section 122 of
the digital recording device 120 detects the anti-duplication
control signal out of the information received from the digital
transmission line 101, and judges the control content. The
judgement result is sent to a digital recording section 121.
[0016] If the judgement result of the anti-duplication control
signal from the anti-duplication control signal detection section
122 indicates permission of recording of the digital information
inputted through the digital transmission line 101, then the
digital recording section 121 converts the input digital signal to
a digital information suitable for recording, and writes it in the
recording medium 123, that is, recording is performed. On the other
hand, if the judgement result of the anti-duplication control
signal from the anti-duplication control signal detection section
122 indicates duplication inhibition, then the digital recording
section 121 does not perform recording processing of the input
digital information.
[0017] Further, if the judgement result of the anti-duplication
control signal from the anti-duplication control signal detection
section 122 indicates permission of recording of only the first
generation, then the digital recording section 121 converts the
input digital signal to a digital information suitable for
recording, and writes it in the recording medium 123, that is,
recording is performed, and additionally, converts the
anti-duplication control signal in the form of additional
information to a signal for indicating duplication inhibition
(duplication inhibition of next generation), and records it in the
recording medium 123. Therefore, the video signal can not be
duplicated further using the recording medium 123 in which the
duplicated information is recorded.
[0018] As described herein above, in the case of digital connection
that the main information signal and anti-duplication control
signal added as an additional information are supplied to a
recording device in the form of digital signal, because the
anti-duplication control signal is contained in the digital data to
be transmitted, duplication prevention control such as duplication
inhibition is performed consistently in a recording device using
the anti-duplication control signal.
[0019] In the case of a duplication prevention control method in
which the above-mentioned difference in AGC system or the
difference in APC characteristics between a VTR and monitor
receiver is used, a pseudo sync signal is inserted in the video
signal recorded in a recording medium or the phase of color burst
signal is inverted partially. In other word, this method involves
processing as described herein above on the sync signal portion,
hence a video signal which provides a normal image can undesirably
duplicated after the sync signal is changed. The duplicated video
signal can be duplicated repeatedly.
[0020] In the case of a duplication prevention control method
utilizing the difference in AGC system or the difference in APC
characteristics between a VTR and monitor receiver, a video signal
is undesirably recorded normally depending on the AGC system or APC
characteristics of the recording device side, a video signal can be
duplicated even without changing sync signal portion. As described
herein above, it can happen that even such passive duplication
prevention does not work.
[0021] In the case of a device which involves the digitized video
signal described herein above using FIG. 1, if the position where
an anti-duplication control signal is recorded is recognized, then
it is possible to duplicate the video signal by changing the
portion where the anti-duplication control signal is recorded or by
removing the anti-duplication control signal.
[0022] In the case that the digital playback device in FIG. 1 is,
for example, a digital VTR, in order to monitor the played back
video signal and audio signal, only both the video signal, that is
the main information signal, and audio signal are converted to an
analog signal through a D/A conversion circuit 113 and guided to an
analog output terminal 114 connected usually to a monitor
receiver.
[0023] As described herein above, though the playback device is a
device for playing back digital signals, the anti-duplication
control signal is not contained in the analog signal guided to the
analog output terminal 114. Therefore, in the case of analog
connection that an analog device such as analog VTR is connected to
the analog output terminal 114, duplication of the information
signal is undesirably possible.
[0024] As described herein above, on the video signal from which an
anti-duplication signal added originally on the video signal is
removed and which duplicated thereafter in a recording medium,
there is no anti-duplication control signal. It is not required to
remove an anti-duplication control signal for duplication, hence,
the video signal which is duplicated illegally can be played back
or duplicated without restriction. In this case, illegal
duplication can be operated more easily.
[0025] Further, in the case that a recording medium in which an
illegally duplicated video signal is recorded is used, the image is
played back normally, therefore, a user can not recognize whether
the video signal recorded in the recording medium is a video signal
recorded illegally or not illegally. Hence, if the video signal
recorded in the recording medium is a video signal duplicated
illegally, users do not complain to a supplier who duplicated and
supplied the video signal illegally about the video signal unless
the quality of the played back image is very poor, as the result,
illegally duplicated video signals become abundant.
[0026] In view of the above-mentioned problem, it is the object of
the present invention to provide a method, device, and recording
medium for preventing illegal duplication of information signals
such as video signals and preventing use of video signals
duplicated illegally in order to eliminate the above-mentioned
problem.
SUMMARY OF THE INVENTION
[0027] To solve the above-mentioned problem, the information signal
output control method in accordance with the present invention
involves a method in which a plurality of anti-duplication control
signals of different types generated correlatively each other added
on the information signal is detected, and the output control of
the information signal is performed dependently on detection
condition of the plurality of anti-duplication control signals of
different types.
[0028] In the information signal output control method in
accordance with the present invention, a notice information is
outputted if a specific anti-duplication control signal out of the
plurality of anti-duplication control signals of different types
generated correlatively each other added on the information signal
is missed and playback output of the information signal is not
outputted.
[0029] In the information signal output control method in
accordance with the present invention, one of the plurality of
anti-duplication control signals of different types generated
correlatively each other is a spectrally spread anti-duplication
control signal added on the information signal.
[0030] The information signal duplication prevention method in
accordance with the present invention involves a method in which
when an information signal is duplicated, the information signal on
which the plurality of anti-duplication control signals of
different types generated correlatively each other is added is
duplicated.
[0031] In the information signal duplication prevention method in
accordance with the present invention. one of the plurality of
anti-duplication control signals of different types generated
correlatively each other is a spectrally spread anti-duplication
control signal superimposed on the information signal.
[0032] In the information signal duplication prevention method in
accordance with the present invention, in the case that the
plurality of anti-duplication control signals of different types
added on the information signal is detected and at least any one of
the plurality of anti-duplication control signals of different
types added on the information signal is missed, a notice
information is outputted.
[0033] According to the information signal output control method in
accordance with the present invention, the output control of an
information signal is performed dependently on detection condition
of a plurality of anti-duplication control signals generated
correlatively each other added on the information signal.
[0034] For example, if all the plurality of anti-duplication
control signals added on the video signal is detected or all the
anti-duplication control signals are not detected, the information
signal is judged to be a legally duplicated information signal and
the video signal is outputted.
[0035] On the other hand, if, for example, the anti-duplication
control signal which should be added without exception out of a
plurality of anti-duplication control signals which should be added
on the information signals is not detected, the information signal
is judged to be an information signal from which the
above-mentioned anti-duplication control signal is removed probably
for the purpose of illegal duplication, and the information signal
is controlled so as not to be outputted.
[0036] Hence, the illegally duplicated information signal is not
used. Users will complain against the supplier who has supplied the
illegally duplicated information signal that the information
signals can not be used, the complain lets the supplier recognize
that the information signal can not be illegally duplicated, and
thus illegal duplication of the information signal is
prevented.
[0037] According to the information signal output control method in
accordance with the present invention, if, for example, the
specific anti-duplication control signal which should be added
without exception out of a plurality of anti-duplication control
signals which should be added on the information signal is missed,
the information signal is not outputted, and a notice message for
indicating that this information signal is an illegally duplicated
information signal is outputted instead.
[0038] Hence, the user can recognize clearly that the information
signal to be outputted if it is normal is not outputted not due to
failure of the device for outputting the information signal, but
due to illegal duplication.
[0039] According to the information signal output control method in
accordance with the present invention, one of a plurality of
anti-duplication control signals of different types added on the
information signal is an anti-duplication control signal spectrally
spread and added on the information signal.
[0040] Because the spectrally spread anti-duplication control
signal is added on the information signal as a wide-band low-level
spectral spread signal, it is difficult to remove it intentionally.
Therefore, the spectrally spread anti-duplication control signal
remains consistently on the information signal, the spectrally
spread anti-duplication control signal exists, hence, if other
anti-duplication control signals which should be contained in the
sync signal are not detected due to changing of sync signal, then
the information signal is judged clearly to be an illegally
duplicated information signal.
[0041] According to the information signal duplication prevention
method in accordance with the present invention, in the case that
duplication of the information signal is performed, a plurality of
anti-duplication control signals of different types having the
correlative relation that as long as the one anti-duplication
control signal exists then the other anti-duplication control
signal also exists without exception is added on the information
signal and the information signal is duplicated.
[0042] By adding a plurality of anti-duplication control signals of
different types with correlative generation on the information
signal and by recording the information signal in a recording
medium, if at least one of the plurality of anti-duplication
control signals added on the information signal is missed, the
information signal is judged easily to be an illegally duplicated
information signal.
[0043] According to the information signal duplication prevention
method in accordance with the present invention, one of the
plurality of anti-duplication control signals of different types to
be added on the information signal to be recorded is spectrally
spread and then added on the information signal.
[0044] As described herein above, it is difficult to remove an
anti-duplication control signal intentionally because the
spectrally spread anti-duplication control signal is added on the
information signal as a wide-band low-level spectral spread signal.
Hence, if an illegally duplicated information signal contains the
one spectrally spread anti-duplication control signal and the other
anti-duplication control signal is not detected, this information
signal is judged clearly to be an illegally duplicated information
signal.
[0045] According to the information signal duplication prevention
method in accordance with the present invention, if at least any
one of the plurality of anti-duplication control signals of
different types which should be added normally on the information
signal is missed, a notice information is outputted.
[0046] Thereby, a user can recognize that the information signal
which wanted to be duplicated is an illegally duplicated
information signal.
BRIEF DESCRIPTION OF THE DRAWINGS
[0047] FIG. 1 is a block diagram for illustrating the conventional
structure of a duplication prevention control system.
[0048] FIG. 2 is a block diagram for illustrating one embodiment of
a video signal output device used as the information signal
duplication prevention device in accordance with the present
invention.
[0049] FIG. 3 is a block diagram for illustrating a recording
device for recording a video signal on which two types of
anti-duplication control signals generated correlatively each
other.
[0050] FIG. 3 is a diagram for describing one example of the
anti-duplication control signal.
[0051] FIG. 4 is a set of graphs for describing the relation
between the SS anti-duplication control signal and information
signal in the form of spectrum.
[0052] FIG. 6 is a diagram for describing the video signal used as
the information signal used in the video signal output device shown
in FIG. 2.
[0053] FIG. 7 is a diagram for describing output control of the
video signal in the video signal output device shown in FIG. 2.
[0054] FIG. 8 is a block diagram for illustrating another
embodiment of the video signal output device used as the
information signal duplication prevention device in accordance with
the present invention.
[0055] FIG. 9 is a block diagram for illustrating the video signal
recording playback system for recording the video signal on which
different types of anti-duplication control signals generated
correlatively each other based on the anti-duplication control
signal added already on the video signal.
[0056] FIG. 10 is a diagram for describing output control of the
video signal recorded by the video signal recording playback system
shown in FIG. 9.
[0057] FIG. 11 is a block diagram for illustrating one embodiment
of the video signal recording device used as the information signal
duplication prevention device in accordance with the present
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0058] One embodiment of an information signal output control
method, information signal duplication control method, information
signal duplication prevention device, and information signal
recording medium in accordance with the present invention will be
described in detail with reference to the drawings.
[0059] The Video signal output device and video signal recording
device described hereinafter comprises an information signal output
device and information signal reception device provided as the
information signal duplication prevention device in accordance with
the present invention, and will be described as devices which are
applied to a DVD (digital video disk) recording/playback device
(referred to as DVD device hereinafter) for the purpose of
description. Description of audio signal system will be omitted for
simplification of the description.
[0060] [First Embodiment]
[0061] FIG. 2 is a block diagram for illustrating a video signal
output device (referred to simply as output device hereinafter) of
the first embodiment. In other words, the output device 10 is
corresponding to a playback system of a DVD device in the first
embodiment.
[0062] As shown in FIG. 2, the output device 10 of this embodiment
is provided with a read out section 11, decoding section 12, D/A
conversion circuit 13, output control section 14, SS (SS stands for
spectral spread hereinafter) anti-duplication control signal
detection section 15, copy guard signal detection section 16, and
output control signal generation section 17.
[0063] In FIG. 2, digitized video signals and audio signals and two
types of anti-duplication control signals of SS anti-duplication
control signal S5 and copy guard signal S6 generated correlated
together as the additional information are recorded in a disk 100,
and in this example, the disk 100 is a DVD.
[0064] In the first embodiment, both the SS anti-duplication
control signal S5 and copy guard signal S6 are signals for
indicating generation restriction such as duplication permission of
the first generation, or duplication inhibition or permission of
the video signal, and composed of one bit or several bit. In a
normally made disk, always a video signal on which an SS
anti-duplication control signal S5 and copy guard signal S6 are
both added is recorded.
[0065] The output device 10 of the first embodiment is a device
which performs output control of the video signal dependently on
detection condition of the two types of anti-duplication control
signal as described herein and hereinafter.
[0066] The video signal recorded in the disk 100 used in the output
device 10 of the first embodiment, and two types of
anti-duplication control signal of the SS anti-duplication control
signal S5 and copy guard signal S6 added on the video signal are
described using FIGS. 2 to 5.
[0067] FIG. 3 is a diagram for illustrating a video signal
recording device 20 (referred to simply as recording device
hereinafter) for adding the SS anti-duplication control signal and
copy guard signal on the video signal DV and recording the video
signal DV on which the SS anti-duplication control signal S5 and
copy guard signal S6 are added in the disk 100. In this first
embodiment, the recording device 20 is a device for forming a disk
in which the video signal DV is duplicated legally.
[0068] As shown in FIG. 3, the recording device 20 is provided with
an input terminal T1 for video signals, input terminal T2 for
anti-duplication control signals GD, addition circuits 21 and 24,
copy guard signal generation section 22, SS anti-duplication
control signal generation section 23, and write section 25.
[0069] In this first embodiment, the anti-duplication control
signal DG is inputted through the input terminal T2 in the form of
1 bit signal for, for example, inhibiting duplication of the video
signal, and supplied to the copy guard signal generation section 22
and SS anti-duplication control signal generation section 23.
[0070] The copy guard signal generation section 22 generates a copy
guard signal S6 based on the anti-duplication control signal GD.
The SS anti-duplication control signal generation section 23
generates SS anti-duplication control signals S5 by spectrally
spreading anti-duplication control signals GD correspondingly to
the indication from copy guard signal generation section 22.
[0071] In the first embodiment, the copy guard signal S6 is an
anti-duplication control signal so-called CGMS. FIG. 3 is a diagram
for describing a copy guard signal S6. In FIG. 3, 1H indicates 1
horizontal interval. In the first embodiment, a copy guard signal
S6 is superimposed, for example, on the 20-th horizontal interval
of the vertical retrace line erasing period of the video
signal.
[0072] In this case, 20 bits of additional information is
superimposed on the 20-th horizontal interval of the vertical
retrace line erasing period, and 1 bit to several bits out of the
20 bit additional information is used as a copy guard signal S6. In
the FIG. 3, out of signals which are superimposed on the 20-th
horizontal interval, the signal REF is a reference signal for
indicating that the signal superimposed on this horizontal interval
is a copy guard signal.
[0073] In the first embodiment, the copy guard signal S6 generated
in the copy guard signal generation section 22 is supplied to the
addition circuit 21, and added on the 20-th horizontal interval of
each vertical retrace line erasing period of the video signal DV as
shown in FIG. 3.
[0074] A PN (Pseudorandom Noise) series code (referred to as PN
code hereinafter) is used as a spread code for the SS
anti-duplication control signal S5, and a narrow-band high-level
anti-duplication control signal GD is spectrally spread, then,
superimposed on the video signal DV in the same time and the same
frequency as a wide-band low-level signal.
[0075] FIG. 4 is a set of graphs for describing the relation
between the anti-duplication control signal and the main
information signal, namely the video signal in this example. An
anti-duplication control signal contains a small quantity of
information and a signal of low bit rate, and a narrow-band signal.
An anti-duplication control signal is changed to a wide-band signal
as shown in FIG. 4(b) by being subjected to spectral spread. When,
the level of a spectrally spread signal becomes low in inverse
proportion to the enlargement ratio of the band.
[0076] This spectrally spread signal, namely the SS
anti-duplication control signal S5, is superimposed on the
information signal. When, an SS anti-duplication control signal S5
is superimposed on the video signal with a lower level than the
dynamic range of the video signal which is involved as an
information signal as shown in FIG. 4(c).
[0077] On the other hand, as described hereinafter, when inversion
spectral spread is performed in order to detect the SS
anti-duplication control signal S5, the spectrally spread signal is
restored again as a narrow-band signal. By giving a sufficient band
spread ratio, power of the anti-duplication control signal after
inversion spread exceeds that of the information signal and such
sufficient spread ratio enables the anti-duplication control signal
to be detected.
[0078] In this case, the SS anti-duplication control signal S5
superimposed on the video signal is superimposed on the video
signal in the same time and the same frequency, therefore, it is
impossible to remove or change the anti-duplication control signal
by using frequency filter or simple replacement of the
information.
[0079] As described herein above, the SS anti-duplication control
signal S5 superimposed on the video signal will not be removed and
is supplied consistently together with the video signal.
[0080] The SS anti-duplication control signal S5 generated in the
SS anti-duplication control signal generation section 23 is
supplied to the addition circuit 24, and superimposed on the video
signal VD on which the copy guard signal S6 is added.
[0081] The video signal VD on which the SS anti-duplication control
signal S5 and copy guard signal S6 are added is supplied to the
write section 25, and recorded in the disk 100. In the first
embodiment, the write section 25 performs also A/D conversion and
coding processing of the video signal to generate the video signal
to be recorded in the disk 100.
[0082] As described herein above, the recording device 20 of the
first embodiment generates always also the SS anti-duplication
control signal S5 when the copy guard signal S6 is generated.
Further as shown in FIG. 6, the video signal VD on which the copy
guard signal S6 and SS anti-duplication control signal S5 generated
correlatively each other are superimposed is recorded in the disk
100.
[0083] Next, the structure and operation of the output device 10
which plays back the disk 100, in which the video signal having the
SS anti-duplication control signal S5 and copy guard signal S6
added thereon is recorded, and outputs the video signal recorded in
the disk 100 as described herein above is described.
[0084] The read out section 11 of the output device 10 extracts the
playback video signal component S2 from the signal S1 obtained by
playing back the disk 100, and supplies it to the decoding section
12, SS anti-duplication control signal detection section 15, and
copy guard signal detection section 16. This playback video signal
component S2 contains also the SS anti-duplication control signal
S5 and copy guard signal S6 as described herein above.
[0085] The decoding section 12 performs decoding processing on the
playback video signal component S2 to generate a digital video
signal S3, and supplies it to the D/A conversion circuit 13. The
D/A conversion circuit 13 performs D/A conversion on the digital
video signal S3 to generate an analog video signal S4 having the
sync signal, and supplies it to the output control section 14.
[0086] On the other hand, the SS anti-duplication control signal
detection section 15 is provided with a PN code generator and
multiplication circuit, performs inversion spectral spread to
extract the SS anti-duplication control signal S5 spectrally spread
and superimposed on the video signal, and supplies it to the output
control signal generation section 17 as the original
anti-duplication control signal S5 before spectral spread.
[0087] In detail, when the SS anti-duplication control signal S5 is
generated by performing spectral spread, the SS anti-duplication
control signal detection section 15 generates a PN code string
having the same pattern at the same timing as the video signal
component S2, and extracts the original anti-duplication control
signal SS before spectral spread from the video signal component S2
by performing inversion spectral spread using this PN code string,
and outputs it.
[0088] The copy guard signal detection section 16 extracts the copy
guard signal S6 which is superimposed on the 20-th horizontal
interval of the vertical retrace line erasing period of the video
signal component S2, and supplies it to the output control signal
generation section 17.
[0089] The output control signal generation section 17 generates
the output control signal S7 for controlling the output control
section 14 dependently on existence of the copy guard signal
S6.
[0090] FIG. 7 is a diagram for describing operation of the output
control signal generation section 17 for generating an output
control signal S7 dependently on existence of the copy guard signal
S6.
[0091] In the first embodiment, if both the SS anti-duplication
control signal S5 and copy guard signal S6 are detected as shown in
FIG. 7, or if both the SS anti-duplication control signal S5 and
copy guard signal S6 are not detected, the output control signal
generation section 17 generates a control signal S7 which functions
to output the playback video signal S4, and supplies it to the
output control section 14.
[0092] If only any one of the anti-duplication control signal S5
and copy guard signal S6 is detected, the output control signal
generation section 17 generates a control signal S7 for inhibiting
output of the playback video signal S4, and supplies it to the
output control section 14.
[0093] Because of the reason described herein under, output of the
playback video signal S4 can be controlled dependently on existence
of the anti-duplication control signal S5 and copy guard signal S6
as described herein above.
[0094] In detail, in the first embodiment, a pair of two
anti-duplication control signals of the SS anti-duplication control
signal S5 and copy guard signal S6 is added on the video signal
recorded in the disk 100. Therefore, both the SS anti-duplication
control signal S5 and copy guard signal S6 are added on the video
signal as long as the video signal is a video signal duplicated
legally.
[0095] However, as described herein above, in the case of the
anti-duplication control signal added in the vertical retrace line
erasing period like the copy guard signal S6 in the first
embodiment, the anti-duplication control signal is easily removed
because the addition position where the copy guard signal S6 is
added in the video signal is apparent. Moreover, even if all the
signals in the vertical retrace line erasing period are replaced
entirely, the video signal in the effective picture interval for
forming a picture is affected not severely.
[0096] Hence, in the case that a recording device which performs
duplication prevention control dependently on the copy guard signal
S6 and can not perform duplication prevention control dependently
on the SS anti-duplication control signal S5 is used, the video
signal can be undesirably duplicated once at least the copy guard
signal S6 is removed.
[0097] Focusing on this point, when the output device 10 of the
first embodiment does not detect at least any one of a pair of SS
anti-duplication control signal S5 and copy guard signal S6 added
on the video signal, the output device 10 judges that the video
signal, which is to be played back and outputted, is a video signal
which was duplicated illegally, and controls the video signal so as
not to be outputted as described herein above.
[0098] In the first embodiment, if both the anti-duplication
control signal S5 and copy guard signal S6 are not detected, the
output control signal generation section 17 generates a control
signal S7 which functions to output the playback video signal S4
and supplies it to the output control section 14. Such control is
performed because in some cases the SS anti-duplication control
signal S5 and copy guard signal S6 are not added originally on the
video signal, for example, in the case of a picture taken by a user
itself using a video camera or a picture for free duplication.
[0099] If both the anti-duplication control signal S5 and copy
guard signal S6 are not detected as described herein above, it is
considered that an anti-duplication control signal is not added
originally on the video signal recorded in the disk 100. Further it
is considered that the SS anti-duplication control signal S5 is not
removed for the purpose of illegal duplication because it is
difficult to remove illegally the SS anti-duplication control
signal S5 as described hereinafter. Therefore in this case, the
output device 10 of this embodiment controls so as to output the
playback video signal S4.
[0100] The output device 14 performs output control of the playback
video signal S4 based on the control signal S7 supplied from the
output control signal generation section 17. The output control
section 14 does not output the playback video signal S4 if the
control signal S7 supplied from the output control signal
generation section 17 is a signal which indicates inhibition of
output of the video signal, and on the other hand, outputs the
playback video signal S4 if the control signal S7 supplied from the
output control signal generation section 17 is a signal which
indicates permission of output of the video signal.
[0101] As described herein above, if the video signal recorded in
the disk 100 lacks at least any one of anti-duplication control
signals added on the video signal out of two types of
anti-duplication control signals generated correlatively each
other, the output device 10 of the first embodiment judges the
video signal recorded in the disk 100 to be a video signal
duplicated illegally, and does not output the playback signal S4
played back from the disk 100.
[0102] On the other hand, if both two types of anti-duplication
control signals S5 and S6 added on the video signal recorded in the
disk 100 are detected, the output device 10 judges the video signal
to be a video signal duplicated legally, and then outputs the
playback video signal S4 played back from the disk 100.
[0103] Hence, in the output device 10 of the first embodiment, if
the video signal lacks at least any one of the SS anti-duplication
control signal S5 and copy guard signal S6, then the playback video
signal S4 played back from the disk 100 will not be outputted, it
is possible not to use an illegally duplicated video signal.
Therefore, illegal duplication of a video signal itself becomes
meaningless, and illegal duplication itself of an information
signal such as video signal is prevented effectively.
[0104] In the first embodiment, one of two types of
anti-duplication control signal is an SS anti-duplication control
signal S5 generated by spectral spread and is superimposed on the
video signal in the same time region and frequency band. Hence, it
is possible to remove intentionally the SS anti-duplication control
signal S5 from the video signal recorded in the disk 100 as
described hereinbefore.
[0105] As described herein above, because the SS anti-duplication
control signal S5 is difficult to be removed, by generating
correlatively each other the SS anti-duplication control signal S5
and another anti-duplication control signal and by adding both on
the video signal, output control for playing back and outputting of
the video signal are performed adequately dependently on existence
of two types of anti-duplication control signals.
[0106] For generating the SS anti-duplication control signal S5 to
be superimposed on the video signal to be recorded in the disk 100,
generation start timing of a PN code string used for spectral
spread is set with reference to the video sync signal as the
reference signal. Hence, by using the video sync signal as the
reference signal also for inversion spectral spread, the PN code
string for inversion spread can be generated at the same timing
with respect to the video signal on which the SS anti-duplication
control signal is superimposed.
[0107] Hence, in the SS anti-duplication control signal detection
section 15, because it is not necessary to perform phase control,
in which the PN code string for spectrally spreading the
anti-duplication control signal superimposed on the video signal
component S2 is detected using, for example, a sliding correlator,
and the PN code string for inversion spread is generated at the
same timing, the anti-duplication control signal is extracted
rapidly by inversion spectral spread.
[0108] As shown in FIG. 7, in the output device 10 of the first
embodiment, because the SS anti-duplication control signal S5 and
copy guard signal S6 are generated correlatively each other, and
both the SS anti-duplication control signal S5 and copy guard
signal S6 are always added on the video signal, in the case that
only any one of anti-duplication control signals is detected, the
video signal is not outputted.
[0109] In consideration of duplication, even if both the SS
anti-duplication control signal S5 and copy guard signal S6 are
detected and then the video signal is outputted, the video signal
is prevented from being duplicated by performing duplication
prevention control based on the anti-duplication control signal as
long as at least any one of two types of anti-duplication control
signal added on the video signal is detected.
[0110] Hence, only when both the SS anti-duplication control signal
S5 and copy guard signal S6 are not detected as shown in FIG. 7,
the video signal recorded in the recording medium 100 is allowed to
be duplicated.
[0111] Further as described hereinafter, when a recording medium,
in this embodiment the disk 100 in which the video signal is
recorded, is manufactured, in some cases, a recording medium on
which a new SS anti-duplication control signal generated
correlatively with the copy guard signal such as CGMS, which has
been already distributed popularly, is added is distributed
later.
[0112] In the case that at least the specific anti-duplication
control signal which should be added on the video signal, the copy
guard signal S6 called CGMS in this first embodiment, is detected,
or in the case that both the copy guard signal S6 and SS
anti-duplication control signal S5 are not detected, the playback
video signal is controlled so as to be outputted.
[0113] [Second Embodiment]
[0114] Next, the second embodiment of the video signal output
device in accordance with the present invention is described.
[0115] In the output device 10 of the first embodiment described
herein above, if only any one of the SS anti-duplication control
signal S5 and copy guard signal S6 is detected, then the video
signal to be outputted is judged to be a video signal which was
duplicated illegally, and the playback video signal S4 played back
from the disk 100 is not allowed to be outputted. Thereby, for
example, it is prevented that the video signal which was duplicated
illegally by removing intentionally the copy guard signal S6 is
used.
[0116] Hence, even if the duplication inhibited video signal is
duplicated, the video signal is not used, therefore as the result,
illegal duplication of the video signal is prevented.
[0117] However, in the case of the output device 10 of the first
embodiment, if the video signal recorded in the disk 100 is not
outputted because, for example, the copy guard signal S6 added on
the video signal is removed intentionally and the video signal is
an illegally duplicated video signal, no image is displayed on, for
example, a monitor receiver which receives supply of the video
signal from the output device 10.
[0118] In such case, a user can not identify whether an image is
not displayed due to a problem of the disk 100 or an image is not
displayed due to a problem of the output device 10 or monitor.
[0119] To identify the cause, the output device 20 of the second
embodiment judges the played back video signal to be a signal
illegally duplicated if, for example, only the SS anti-duplication
control signal S5 is detected out of two types of anti-duplication
control signal of the SS anti-duplication control signal S5 and
copy guard signal S6 added on the video signal like the output
device 10 of the first embodiment, and the output device 20 outputs
a notice message instead of the video signal.
[0120] The user who wants to use the illegally duplicated video
signal receives a notice for indicating that the video signal which
the user wants to use is an illegally duplicated video signal.
[0121] FIG. 8 is a block diagram for illustrating an output device
30 of the second embodiment. As shown in FIG. 8, the output device
30 of the second embodiment is provided with a read out section 11,
decoding section 12, D/A conversion circuit 13, output control
section 14, SS anti-duplication control signal detection section
15, copy guard signal detection section 16, output control signal
generation section 17, notice message generation section 18, and
switch circuit 19.
[0122] Components other than the notice message generation section
18 and switch circuit 19 is the same components as the components
used in the output device 10 of the above-mentioned first
embodiment, however, the output control signal generation section
17 is different from the output control signal generation section
17 of the first embodiment in that the output control signal
generation section 17 of the second embodiment generates control
signals to be supplied also to the notice message generation
section 18 and switch circuit 19.
[0123] As the first embodiment described herein above, in the disk
100, the video signal on which the SS anti-duplication control
signal S5 and copy guard signal S6 generated correlatively each
other when the video signal on which no anti-duplication control
signal is added is recorded in the disk 100.
[0124] The notice message generation section 18 generates and
outputs a display message for noticing a user that the video signal
recorded in the disk 100 is an illegally duplicated video signal
correspondingly to the control signal S8 supplied from the output
control signal generation section 17. In the second embodiment, the
notice message generation section 18 uses so-called OSD (on screen
display), and generates a notice message of 1 screen and outputs
it.
[0125] The switch circuit 19 switches to output a signal from the
output control section 14 or to output a signal from the notice
message generation section 18 correspondingly to the control signal
S9 supplied from the output control signal generation section
17.
[0126] The output control signal generation section 17 of the
output device 20 receives supply of an output signal from the SS
anti-duplication control signal detection section 15 and copy guard
signal detection section 16, and then judges whether the video
signal component S2 contains the SS anti-duplication control signal
S5 and copy guard signal S6 therein, and correspondingly to the
judgement result, generates and outputs control signals S7, S8, and
S9 to be supplied to the output control section 14, notice message
generation section 18, and switch circuit 19 respectively.
[0127] In detail, like the output control signal generation section
17 of the above-mentioned first embodiment, the output control
signal generation section 17 of the second embodiment judges the
video signal recorded in the disk 100 to be a legally recorded
video signal if the output control signal generation section 17
judges the video signal component S2 to be a video signal component
which contains both the SS anti-duplication control signal S5 and
copy guard signal S6 or judges the video signal component S2 to be
a video signal component which does not contain both the SS
anti-duplication control signal S5 and copy guard signal S6.
[0128] In this case, the output control signal generation section
17 generates a control signal S7 for controlling the output control
section 14 to output a playback video signal S4, and generates and
outputs a control signal S9 for switching the switch circuit 19 to
output the signal supplied from the output control section 14.
[0129] The output control signal generation section 17 judges the
video signal recorded in the disk 100 to be an illegally duplicated
video signal if the SS anti-duplication control signal S5 or copy
guard signal S6 is missed. In this case, the output control signal
generation section 17 generates a control signal S8 for controlling
the notice message generation section 18 to generate and output a
notice message, and generates and outputs a control signal S9 for
switching the switch circuit 19 to output the signal supplied from
the notice message generation section 18.
[0130] As described herein above, the output device 20 of the
second embodiment outputs the playback video signal S4 if the video
signal recorded in the disk 100 contains both the SS
anti-duplication control signal S5 and copy guard signal S6 or does
not contain both the SS anti-duplication control signal S5 and copy
guard signal S6. On the other hand, the output device 20 outputs a
notice message instead of the playback video signal S4 if any one
of the SS anti-duplication control signal S5 and copy guard signal
S6 is missed.
[0131] As the notice message, various messages which notice a user
that the video signal wanted to be played back is an illegally
duplicated video signal, for example, "this video signal is an
illegally duplicated video signal, and can not be played back
normally" may be used.
[0132] Thereby, for example, a video signal which was duplicated
illegally by removing the copy guard signal S6 is controlled so as
not to be outputted and, in the case that the playback video signal
is not outputted, a notice message is displayed so that a user
receives a notice which indicates that the video signal recorded in
the disk is an illegally duplicated video signal.
[0133] In this case, the user can take an action such as complain
to the supplier who supplied the illegally duplicated video signal,
and thus illegal duplication of the video signal can be prevented
effectively from being duplicated.
[0134] In the second embodiment, the case that the notice message
of 1 screen formed using OSD is displayed is described, however,
the present invention is by no means limited to the case.
[0135] For example, a notice message may be displayed with the
playback video signal using superimposition. In this case, a notice
message displayed by way of superimposition may cover the more than
half portion of the image played back from the playback video
signal S4 in order to prevent the played back image from being
used. In this case, a notice message notices a user that the played
back video signal is an illegally duplicated video signal, and also
the user can recognize that the video signal output device or
monitor receiver is not in failure.
[0136] Alternatively, a notice for indicating that the video signal
wanted to be played back is an illegally duplicated video signal
may be outputted by way of voice message instead of a display
notice message. In this case, the playback video signal may not be
outputted in order to prevent the video signal from being used.
[0137] Further alternatively, in the case that the video signal to
be outputted is an illegally duplicated video signal, the playback
video signal may be subjected to so-called scrambling in order to
prevent a normal image from being played back, or scrambling on the
playback video signal may be combined with a notice message by way
of superimposition. A method in which a notice message by way of
superimposition and the image of the playback video signal S4 are
outputted and thereafter displaying of the image is discontinued
may be used.
[0138] Yet alternatively, voice may be mute. In this case, it is
possible to notice a user that the video signal wanted to be played
back and outputted is an illegally duplicated video signal clearly
by combining the mute voice and a notice message display as
described herein above.
[0139] Also in the output device 30 of the second embodiment, like
the output device 10 of the above-mentioned first embodiment, in
the case that duplication is considered, as long as at least any
one of two anti-duplication control signals added on the video
signal is detected, even if both the SS anti-duplication control
signal S5 and copy guard signal S6 are detected and the video
signal is outputted, the video signal is protected from being
duplication by performing duplication prevention control based on
the anti-duplication control signal.
[0140] Therefore, as shown in FIG. 7, only when both the SS
anti-duplication control signal S5 and copy guard signal S6 are not
detected, the video signal recorded in the recording medium 100 is
outputted and duplicated.
[0141] [Third Embodiment]
[0142] In the first and second embodiments described hereinbefore,
the video signal on which the SS anti-duplication control signal S5
and copy guard signal S6 generated correlatively each other have
been added is recorded originally in the disk 100. Therefore in the
case that any one of the SS anti-duplication control signal S5 or
the copy guard signal S6 which should be added on the video signal
recorded in the disk 100 is missed, the video signal is judged to
be a video signal from which the SS anti-duplication control signal
SS or copy guard signal S6 was removed for the purpose of illegal
duplication of the video signal.
[0143] However, devices and video tapes which output the video
signal having, for example, the copy guard signal called as CGMS
and micro-vision have been already distributed popularly. In such
case that the video signal contains already the copy guard signal,
output control and duplication control should be performed based on
this copy guard signal.
[0144] However, in the case of the above-mentioned first and second
output devices 10 and 30, as shown in FIG. 7, if the video signal
does not contain any one of the SS anti-duplication control signal
S5 and copy guard signal S6, the playback video signal is
controlled so as not to be outputted.
[0145] In the output device of the third embodiment, if a specific
anti-duplication control signal which should be added on the video
signal, namely copy guard signal such as CGMS, is detected, then
the playback video signal is controlled so as to be outputted.
[0146] Further in the case that the video signal on which the copy
guard signal is added is transmitted or recorded, for example, the
SS anti-duplication control signal is generated based on this copy
guard signal, and the SS anti-duplication control signal is added
on the video signal, thereby, the video signal transmitted or
recorded on a recording medium is prevented from being duplicated
illegally.
[0147] The case that the SS anti-duplication control signal is
added additionally on the video signal based on the copy guard
signal added already on the video signal when the video signal is
transmitted or duplicated is described herein under.
[0148] FIG. 9 is a block diagram for illustrating a video signal
recording playback system (referred to simply as recording playback
system hereinafter) for generating the SS anti-duplication control
signal, adding it on the video signal, and recording the added
video signal in a recording medium based on the copy guard signal
added already on the video signal as described herein above. In
this third embodiment, the recording playback system 40 corresponds
to, for example, a DVD device.
[0149] The recording playback system 40 is provided with a read out
section 41, addition circuit 42, copy guard signal detection
section 43, SS anti-duplication control signal generation section
44, duplication control section 45, and write section 46 as shown
in FIG. 9.
[0150] In the third embodiment, the video signal on which only the
copy guard signal called as CGMS is added in the disk 300. In the
third embodiment, the copy guard signal added on the video signal
is an information for indicating generation restriction of
duplication, for example, an information for indicating duplication
permission of only one generation.
[0151] In the third embodiment, the read out section 41 the digital
video signal component S11 read out from the disk 300, and outputs
an analog video signal component S12. The analog video signal
component is supplied to the addition circuit 42 and copy guard
signal detection section 43.
[0152] The copy guard signal detection section 43 detects the copy
guard signal S13 added on the 20-th horizontal interval of the
vertical retrace line erasing period of the analog video signal
component S12, and supplies it to the SS anti-duplication control
signal generation section 44 and duplication control section
45.
[0153] As described herein above, in the third embodiment, the copy
guard signal S13 is a duplication generation restriction
information for permitting only the first generation duplication.
Hence, the SS anti-duplication control signal generation section 44
generates the SS anti-duplication control signal S14 which
indicates duplication inhibition based on the copy guard signal
S13, and supplies it to the addition circuit 42.
[0154] The addition circuit 42 superimposes the SS anti-duplication
control signal S14 on the analog video signal component S12. The
analog video signal on which the SS anti-duplication control signal
S14 is superimposed is supplied to the write section 46.
[0155] In the third embodiment, because the copy guard signal S13
is the information for permitting only the first generation
duplication, the duplication control section 45 generates a control
signal CTL for permitting duplication, and supplies it to the write
section 46. If the copy guard signal S13 is a copy guard signal for
indicating duplication inhibition, the duplication control section
45 generates a control signal CTL for inhibiting duplication, and
supplies it to the write section 46.
[0156] The write section 46 performs A/D conversion processing and
coding processing on the analog video signal supplied from the
addition circuit 42 to generate a digital video signal component
S15 to be written in the disk 100, and writes it in the disk
100.
[0157] If the control signal CTL is a signal for inhibiting
duplication, the write section 46 does not write the video signal
in the disk 100.
[0158] Because the copy guard signal S13 is a copy guard signal for
permitting only the first generation duplication, therefore in the
recording playback system 40 of the third embodiment, the copy
guard signal added on the video signal supplied from the addition
circuit 42 is changed from the information for permitting the first
generation duplication to the information for inhibiting
duplication.
[0159] As described herein above, in the recording playback system
40 of the third embodiment, the SS anti-duplication control signal
S14 is generated based on the copy guard signal S13 added already
on the video signal, and the SS anti-duplication control signal is
superimposed on the video signal to be recorded in the disk 100.
Therefore, the video signal in the disk 100 on which both the copy
guard signal and SS anti-duplication control signal generated
correlatively each other are added is recorded in the disk 100.
[0160] As described herein above, the video signal recorded in the
disk 100 together with the copy guard signal and SS
anti-duplication control signal generated correlatively with the
copy guard signal added on the video signal is played back and
outputted using the output device 10 or 30 of the above-mentioned
first or second embodiment.
[0161] Herein under, the case in which the video signal is played
back from the disk 100 in which the video signal is recorded by
mans of the recording playback system 40 and is outputted using the
output device 10 or 30 shown in FIG. 2 or FIG. 8 is described.
[0162] In the case of the third embodiment, the SS anti-duplication
control signal S14 is generated later based on the copy guard
signal added already on the video signal and superimposed on the
video signal. Hence, if the SS anti-duplication control signal S14
is not added on the video signal and as long as the copy guard
signal S13 is added on the video signal, this video signal is
judged to be a video signal duplicated legally.
[0163] In other words, the disk 300 shown in FIG. 9 in which the
video signal having the copy guard signal added thereon is recorded
is a disk in which the video signal is duplicated legally.
Therefore, unlike the above-mentioned first and second embodiments,
the video signal recording playback system 40 does not control so
that the video signal recorded in the disk 300 is not outputted
merely because the SS anti-duplication control signal is not
added.
[0164] Hence, in the third embodiment, in the case that the disk
100 in which the video signal is recorded or the disk 300 in which
the video signal having the copy guard signal S13 added thereon is
played back using the recording playback system 40, control in the
output control signal generation section 17 of the above-mentioned
output device 10 or 30 is different.
[0165] FIG. 10 is a diagram for describing control of the output
control signal generation section 17 of the output device 10 or 30
in the case that the SS anti-duplication control signal is
generated based on the copy guard signal, the SS anti-duplication
control signal is additionally added on the video signal, and the
video signal is played back and outputted when the copy guard
signal is already added on the video signal.
[0166] In the third embodiment, the output control signal
generation section 17 of the output device 10 or 30 judges the
video signal to be a legally duplicated video signal when at least
the copy guard signal S13 is detected as shown in FIG. 10, and
supplies a control signal S7 for controlling the output control
section 14 so as to output the played back video signal.
[0167] Further, in the case that both the copy guard signal S13 and
SS anti-duplication control signal S14 are not detected, the output
control signal generation section 17 judges the video signal to be
a video signal having originally no anti-duplication control signal
and a video signal of free duplication, and generates a control
signal S7 for controlling so that the video signal is outputted and
supplies the control signal S7 to the output control section
14.
[0168] Then, if the copy guard signal S13 which should be added on
the video signal is not detected and the SS anti-duplication
control signal S14 is detected, the output control signal
generation section 17 judges the video signal to be a video signal
from which the copy guard signal S13 is removed for the purpose of
illegal duplication of the video signal, and the video signal is
not outputted.
[0169] As described herein above, only for the case that the copy
guard signal S13 which should be added on the video signal is not
detected and the SS anti-duplication control signal S14 generated
based on the copy guard signal S13 is detected, the video signal is
not outputted.
[0170] By controlling as described herein above, in the case of the
disk 300 in which the video signal having only copy guard signal
S13 added thereon and also in the case of the disk 100 in which the
video signal having the copy guard signal S13 and the SS
anti-duplication control signal S14 generated based on the copy
guard signal S13 added thereon is recorded, only the video signal
duplicated legally is outputted as described herein above.
[0171] Further as described herein above, in the case that the copy
guard signal added already on the video signal is an information
for indicating generation restriction duplication, the SS
anti-duplication control signal is generated based on this copy
guard signal, it is added on the video signal in addition to the
copy guard signal, thereby, illegal duplication after legal
duplication can be prevented effectively.
[0172] Like the output devices 10 and 30 of the above-mentioned
first and second embodiments, in the third embodiment, in the case
that duplication is considered, as long as at least any one of two
anti-duplication control signals added on the video signal is
detected, by performing duplication prevention control based on the
anti-duplication control signal, both the SS anti-duplication
control signal S5 and copy guard signal S6 are detected, and the
video signal is prevented from being duplicated even in the case
that the video signal is outputted.
[0173] In the third embodiment, the case that the copy guard signal
detection section 43 detects the copy guard signal called as CGMS
is described, however, the present invention is by no means limited
to the case, alternative case, that a plurality of anti-duplication
control signals such as CGMS and macro-vision is detected, output
control is performed based on the detected anti-duplication control
signal, and the SS anti-duplication control signal S14 is generated
based on the detected anti-duplication control signal, may be
used.
[0174] [Fourth Embodiment]
[0175] Next, a recording device 50 which functions as a information
signal duplication prevention device in accordance with the present
invention is described.
[0176] FIG. 11 is a block diagram for illustrating the recording
device 50 of the fourth embodiment. In the fourth embodiment, the
recording device 50 corresponds to a recording system of a DVD
device.
[0177] The recording device 50 is provided with an A/D conversion
circuit 31, coding section 32, first anti-duplication control
signal detection section 33, second anti-duplication control signal
detection section 34, write section 35, output control signal
generation section 36, duplication control section 37, display
message generation section 38, and LCD (liquid crystal display) 39
as shown in FIG. 11. A disk 200 is a DVD in which the video signal
is written by the recording device 50.
[0178] The recording device 50 receives supply of an analog video
signal outputted from the output device 10 or 20 described in the
above-mentioned first, second, or third embodiment. The A/D
conversion circuit 31 converts the supplied analog video signal to
a digital video signal S21, and the digital video signal S21 is
supplied to the coding section 32, first anti-duplication control
signal detection section 33, and second anti-duplication control
signal detection section 34.
[0179] Upon receiving supply of the digital video signal S21, the
coding section 22 performs coding processing such as removal of the
video sync signal and data compression of the digital video signal
to generates a digital video signal S22 for recording to be
supplied to the disk 200, and supplies it to the write section
35.
[0180] The first anti-duplication control signal detection section
33 has the same function as the SS anti-duplication control signal
detection section 15 of the above-mentioned output devices 10 and
30. In the fourth embodiment, the first anti-duplication control
signal detection section 33 detects the SS anti-duplication control
signal S23 that is an anti-duplication control signal spectrally
spread and superimposed on the video signal S21, and supplies it to
the output control signal generation section 36.
[0181] The second anti-duplication control signal detection section
34 has the same function as the copy guard signal detection section
16 of the above-mentioned output devices 10 and 30. In the fourth
embodiment, the second anti-duplication control signal detection
section 34 detects the copy guard signal S24 that is the
anti-duplication control signal superimposed on the 20-th
horizontal interval of the vertical retrace line erasing period,
and supplies it to the output control signal generation section
36.
[0182] If both the SS anti-duplication control signal S23 and copy
guard signal S24 are detected, the output control signal generation
section 36 supplies the signal having the stricter duplication
information for duplication prevention control out of two signals
to the duplication control section 37. If the SS anti-duplication
control signal S23 and copy guard signal S24 have the same content,
any one of signals is supplied to the duplication control section
37.
[0183] In the fourth embodiment, if both the SS anti-duplication
control signal S23 and copy guard signal S24 are not detected, the
output control signal generation section 36 judges the video signal
supplied to the recording device 30 to be a video signal of free
duplication, and supplies a signal for indicating duplication
permission to the duplication control section 37.
[0184] If only any one of the SS anti-duplication control signal
S23 and copy guard signal S24 is detected, the output control
signal generation section 36 supplies the detected SS
anti-duplication control signal 23 or copy guard signal S24 to the
duplication control section 37.
[0185] As described herein above, if only the SS anti-duplication
control signal S23 is detected out of two anti-duplication control
signals which should be added on the video signal, the supplied
video signal is judged to be an illegally duplicated video signal.
Then, if only the SS anti-duplication control signal S23 is
detected out of two types of anti-duplication control signals as
described herein above, the output control signal generation
section 36 controls the display message generation section 38 so as
to output a notice message.
[0186] The display message generation section 38 generates a notice
message based on the control signal supplied from the output
control signal generation section 36, and supplies it to the LCD
39. As the result, for example, a notice message such as "NO
recording", "NO duplication", or "this is a video signal duplicated
illegally" is displayed on the LCD 39. Hence, a user can recognize
that the video signal wanted to be recorded is an illegally
duplicated video signal.
[0187] Further in this case, the anti-duplication control signal
detected in the first anti-duplication control signal detection
section 33 or second anti-duplication control signal detection
section 34 is not supplied to the duplication control section 37,
but a generated control signal for inhibiting duplication may be
supplied to the duplication control section 37 as the
anti-duplication control signal S25.
[0188] On the other hand, the duplication control section 37 which
receives supply of the anti-duplication control signal from the
output control signal generation section 36 decodes the
anti-duplication control signal and judges whether the video signal
supplied to the recording device 50 is a video signal of
duplication inhibition or duplication permission. Then, the
duplication control section 37 generates a write control signal S16
based on the judgement result, and supplies it to the write section
35, hence, the duplication prevention control such as permission or
inhibition of writing of the video signal S22 is performed.
[0189] If the write control signal S26 is a signal for permitting
writing, the write section 35 writes the video signal S22 in the
disk 200, and if the write control signal S26 is a signal for
inhibiting writing, the write section 35 does not write the video
signal S22.
[0190] As described herein above, if both the SS anti-duplication
control signal S23 and copy guard signal S24 are not detected from
the digital video signal S21, and if both the SS anti-duplication
control signal S23 and copy guard signal S24 are detected, for
example, in the case of a generation restriction information for
permitting only the first generation duplication of the video
signal, the duplication of the video signal is permitted, and the
digital video signal S12 supplied to the write section 29 is
written in the disk 200.
[0191] In other words, if at least any one of the SS
anti-duplication control signal 23 and copy guard signal S24 is
detected, the recording device 50 performs duplication prevention
control based on the detected anti-duplication control signal as
shown in FIG. 10.
[0192] Further like the recording playback system 40 of the
above-mentioned third embodiment, in the case that the copy guard
signal is added already on the video signal, alternative method in
which the SS anti-duplication control signal is generated based on
this copy guard signal, the SS anti-duplication control signal is
superimposed on the video signal in addition to the copy guard
signal added already, and then the video signal is recorded may be
used.
[0193] In such case, like the recording playback system of the
above-mentioned third embodiment, in the case that the copy guard
signal is an information for indicating generation restriction
duplication, illegal duplication after legal duplication is also
prevented effectively.
[0194] By using the output device 10 of the above-mentioned first
embodiment or the output device 30 of the second embodiment as a
playback system and by using a recording playback device or DVD
device having the recording device 50 of the fourth embodiment as a
recording system, in the case that the video signal is recorded in
the disk 200 using this DVD device, a pair of the copy guard signal
and SS anti-duplication control signal generated correlatively is
added on the video signal to be recorded in the disk 200 without
exception.
[0195] When the video signal recorded in the disk 200 is played
back using this DVD device, because two types of anti-duplication
control signals are detected, the video signal is played back
normally.
[0196] However, in the case that the video signal recorded in the
disk 200 is duplicated illegally by removing the copy guard signal
S14 using another recording device, it is possible that the video
signal is not played back normally using this DVD device.
[0197] In other words, because the copy guard signal which should
be added on the video signal is not detected, this DVD device
judges the video signal wanted to be played back to be an illegally
duplicated video signal, and does not play back the video
signal.
[0198] This DVD device performs duplication prevention control
properly based on the detected anti-duplication control signal,
therefore, this DVD device does not duplicate illegally the video
signal.
[0199] In the above-mentioned first, second, third, and fourth
embodiments, the case that the SS anti-duplication control signal
that is a spectrally spread anti-duplication control signal and the
copy guard signal that is a anti-duplication control signal
so-called CGMS are superimposed on the video signal as the
anti-duplication control signal is described, however, the present
invention is by no means limited to the case.
[0200] For example, a method that is a duplication prevention
control method utilizing the difference in AGC system or difference
in APC characteristics, and a method in which duplication
prevention control method so-called macro-vision is used as a pair
and these two types of anti-duplication control signals are used,
may be used.
[0201] In the case of DVD (digital video disk), CD (compact disk),
and MD (small-sized magneto-optic disk called as mini-disk), the
anti-duplication control signal may be recorded in TOC (Table Of
Content) on the innermost or outermost area of a disk or in the
track area called as directory, or may be insertion-recorded on the
separate recording area on the track where video data and audio
data are recorded.
[0202] As described herein above, the anti-duplication control
signal recorded in TOC or directory may be used in the form of a
pair with the SS anti-duplication control signal, so-called CGMS,
or so-called macro-vision, or the anti-duplication control signal
insertion-recorded on the separate area on the track where video
data and audio data are recorded may be used in the form of a pair
with the SS anti-duplication control signal. Other various
anti-duplication control signals may be used.
[0203] The anti-duplication control signal added on the video
signal is not limited to two types, but a plurality of types of
anti-duplication control signals generated correlatively each other
may be added on the video signal.
[0204] In the above-mentioned first, second, and third embodiments,
the case that the information signal on which the anti-duplication
control signal is added or is to be added is the video signal for
the purpose of description, however, the present invention is by no
means limited to the video signal. For example, audio signals or
digital data may be the information signal on which a plurality of
anti-duplication control signals generated correlatively is to be
added.
[0205] In the above-mentioned first, second, and third embodiments,
the output devices 10 and 20 and recording device 30 are described
to be all DVD devices for the purpose of description, however, such
devices are not limited to the DVD device. For example, the present
invention can be applied to playback devices and recording devices
which use VTR and digital VTR, video disk, video CD, mini-disk
called as small-sized magneto-optic disk, and magnetic disk. In
other words, the present invention can be applied to both analog
apparatus such as analog VTR and also to digital apparatus such as
DVD device.
[0206] The present invention can be applied to television receivers
for receiving various television broadcast such as television
broadcast, digital television broadcast, and cable television
broadcast, reception devices for receiving various television
broadcast and supplying the video signal to monitor receivers, and
also to information apparatus such as personal computers for
performing so-called personal computer communication.
[0207] As described herein above, by applying the present invention
to television receivers, reception devices, and information
apparatus, wide spread illegal duplication of information signals
through broadcasting and communication network is also
prevented.
[0208] In the above-mentioned first and second embodiments, if at
least any one of two types of anti-duplication control signals is
not detected, the video signal served as the information signal is
not outputted or a notice message is outputted. Further in the
third embodiment, if only the specific anti-duplication control
signal which is added on the video signal without exception is not
detected, the video signal is not outputted. However, the present
invention is by no means limited to these cases.
[0209] For example, a method, in which if the SS anti-duplication
control signal which should be added as the anti-duplication
control signal is not detected, output of the playback video signal
is inhibited, and if the SS anti-duplication control signal is
detected but the copy guard signal is not detected, a notice
message is outputted, may be used, and similarly, output control
and duplication control may be changed dependently on the detected
anti-duplication control signal or the anti-duplication control
signal which is not detected.
[0210] When a recording medium such as disk on which information
signals such as video signals, audio signals, and digital data are
recorded is manufactured, a disk in which information signals
having a plurality of types of anti-duplication control signals
added thereon may be manufactured by adding a plurality of types of
anti-duplication control signals generated correlatively each
other.
[0211] As described hereinbefore, according to the information
signal output method, information signal duplication prevention
method, information signal duplication prevention device, and
information signal recording medium in accordance with the present
invention, a plurality of anti-duplication control signals
generated correlatively each other is added on the information
signal.
[0212] Thereby, in the case that the specific anti-duplication
control signal out of a plurality of anti-duplication control
signals which should be added on the information signal is missed,
or in the case that different types of anti-duplication control
signals formed originally with correlative generation are added on
the information signal and at least any one of them is missed, this
information signal is judged to be an illegally duplicated
information signal, and output control such as inhibition of the
illegally duplicated information signal is performed.
[0213] Further, in the case that the information signal is an
illegally duplicated information signal, a notice message is
outputted, and the message notices a user that the information
signal wanted to be outputted is an illegally duplicated
information signal.
[0214] Thereby, the user can recognize that the information signal
is an illegally duplicated information signal if the information
signal is in fact an illegally duplicated information signal, and
the user can complain against the supplier who supplied the
illegally duplicated information signal. Thus, it is easy to expose
suppliers who duplicate illegally information signals, and illegal
duplication of the information signal is prevented effectively.
* * * * *