JP2000173177A - Data reproducing device provided with electronic watermark function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a data reproducing device provided with electronic watermark function capable of preventing an electronic watermark data for copy prevention from being simply released and dealing with all data such as the sound digital data, image digital data and computer data. SOLUTION: A microprocessor 11 controlling a whole device is provided. When the electronic watermark data donot exist in a read signal of a DVD 1 obtained by a signal processing circuit 2 and a decoder circuit 3 is detected by an electronic watermark detection circuit 8, the copy prevention data of an effect that it is a first copy are added to the read signal to be outputted from respective systems of an interface circuit 10, an image D/A circuit 6 and a sound D/A circuit 4. When the effect that it is the first copy is detected, the copy prevention data of the effect that it is a second copy are added to be outputted as a regenerative signal, and when the effect that it is the second copy is detected, the output is prohibited.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data reproducing apparatus having a digital watermark function, and more particularly to a data reproducing apparatus having digital watermark data added to image and / or audio data, or recorded without adding the digital watermark data. The present invention relates to a data reproducing apparatus with a digital watermark function capable of outputting a read signal read from a recorded medium as a reproduced signal.

[0002]

2. Description of the Related Art Image and / or audio data is recorded on a video tape, laser disk, floppy disk,
D, CD-R, CD-RW, VCD, DVD, DVD-
R, etc., and can be recorded on such a recording medium. The data recorded on such a recording medium can be reproduced by an appropriate data reproducing device, data exchange between other devices, or another device using a recording device. It can be copied (recorded) on a recording medium.

In this case, if data recorded on a recording medium can be copied onto another recording medium without any restrictions, a copy of the original data originally recorded or a secondary copy thereof will be released without restriction. In other words, data in a state where the data is recorded as it is at first or in a state where a part of the data is corrected is widely distributed, and copyrights and other rights are infringed.

[0004] For this reason, when recording data such as images, voices, computers, etc. on a recording medium, encryption data called an electronic watermark is added to the data, and when a predetermined condition is cleared, it is not possible. There is a digital watermarking device for copy prevention which can take out the reproduced signal or make it possible to copy.

When the recording medium is a DVD, such a digital watermarking device for copy protection is configured as shown in FIG. 3, for example, and optically reads pit information recorded on the DVD 1 so as to optically read the pit information. The focus servo and tracking servo of the read laser beam are controlled based on the control of the microprocessor 7 for controlling the operation of the digital laser. For example, an SPDIF signal of the IEC-958 standard is obtained.

The output of the decoder circuit 3 is converted by the audio D / A circuit 4 into an A output (audio output) signal. At the same time, the output of the decoder circuit 3 is guided to the image D / A circuit 6 via the digital watermark circuit 5, and
/ A circuit 6 converts the signal into a V output (video output) signal.

[0007] Data recorded on the DVD 1 is digitally watermarked, and has a CSS (Content Scramb).
le System), a method of scrambling image data with encrypted data and recording it,
A method of generating noise in an analog signal, which is called a PS (Analog Protection System), is employed.

Accordingly, the digital watermarking circuit 5 cuts off the input to the image D / A circuit 6 based on these digital watermarks,
Image data is prevented from appearing on the V output. The audio system is output normally regardless of the presence or absence of a digital watermark.

The SP output from the decoder circuit 3
The output of the DIF signal is generally a digital transmission format for audio, and the source device does not set the copy prohibition flag.

On the other hand, in a recording medium such as a CD, an SCM
There is a copy protection system called S (Serial Copy Management System), which allows digital copying of original data only once and prohibits secondary copying. Specifically, audio digital data The permission and prohibition of digital copying are determined based on whether or not a copy prohibition flag is present at a predetermined address.

[0011]

A conventional data reproducing apparatus having a digital watermark function employs a method of scrambling image data by CSS encryption, a method of generating APS noise in an analog signal, and the like. However, this is mainly for the purpose of analog copy protection.
The output of the DIF signal is generally a digital transmission format for audio, and the source device does not set the copy prohibition flag.

[0012] Therefore, since a new signal is added or deformed to a portion other than the image signal area, the image reproduced by a general TV monitor device may be affected and the image quality may be degraded.

Further, if the user understands the technical contents, the user can release the prohibition of image copy relatively easily, and digital copy can be easily performed as long as the equipment is available.

On the other hand, as for digital audio, only a copy prohibition flag is added to a predetermined address of digital audio data, and an adapter for releasing copy is currently available on the market. I can't be.

An object of the present invention is to prevent digital watermark data for copy protection from being easily released.
An object of the present invention is to provide a data reproducing apparatus with a digital watermark function that can correspond to audio digital data, image digital data, and the like.

[0016]

In order to solve the above-mentioned problems, a digital watermark data reproducing apparatus according to the present invention employs the following characteristic configuration.

(1) An electronic watermark capable of outputting a read signal read from a recording medium recorded with image and / or audio data added with electronic watermark data or recorded without adding the electronic watermark data as a reproduction signal. In a data reproducing apparatus with a function, a digital watermark detection unit for detecting digital watermark data included in a read signal read from the recording medium; and the read signal based on the digital watermark data detected by the digital watermark detection unit. And output control means for adding copy protection data to the data and outputting the reproduced signal as a reproduction signal.

(2) When the digital watermark detecting means detects that the digital watermark data is not present in the read signal,
Copy protection data consisting of ID code data indicating the first copy is added to the read signal and can be output as a reproduction signal.

(3) The output control means of (1) is activated when the digital watermark detection means detects digital watermark data consisting of an ID code indicating a second copy in the read signal. The output of the read signal as the reproduction signal is prohibited.

(4) When the digital watermark detecting means detects that the digital watermark data is not present in the read signal,
Copy protection data, which is ID code data indicating the first copy, is added to the read signal and output as a reproduction signal, and the read signal includes an electronic code including an ID code indicating the first copy. When watermark data is detected by the digital watermark detection means, copy protection data consisting of ID code data indicating that the data is a second copy is added to the read signal and output as a reproduction signal. When digital watermark data consisting of an ID code indicating a second copy is detected by the digital watermark detection means, the output of the read signal as a reproduction signal is prohibited.

(5) The output control means of any one of (1) to (4) is configured to output the reproduced signal to a digital bus in the form of a digital signal.

(6) The output control means of any one of (1) to (4) is configured to output the reproduced signal in the form of an analog signal.

[0023]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block circuit diagram of a data reproducing apparatus with a digital watermark function according to an embodiment of the present invention, for controlling the entire data reproducing apparatus in order to optically read pit information recorded on a DVD 1. The focus servo and tracking servo of the read laser beam are controlled under the control of the microprocessor 11, and digital data is extracted and error correction is processed by the signal processing circuit 2, demodulated by the decoder circuit 3, and digital watermark detection is performed. An SPDIF signal of, for example, the IEC-958 standard is obtained by sequentially passing through the circuit 8 and the digital watermark generation circuit 9.

The digital watermark detecting circuit 8 is digital watermark detecting means for detecting digital watermark data included in the read signal read from the DVD 1. The digital watermark generating circuit 9 is detected by the digital watermark detecting circuit 8. And a part of output control means capable of adding copy protection data to the read signal based on the digital watermark data and outputting the read signal as a reproduction signal.

The digital watermark generation circuit 9 has four output systems, an SPDIF signal system, a D bus system to a digital bus according to the IEEE 1394 standard, and an image D / A circuit 7.
Analog V output (video output) system and audio D /
The A circuit 4 is an analog A output (audio output) system.

The output form of the audio D / A circuit 4 is an L-channel and R-channel stereo audio signal.
It is a one-channel Dolby audio signal, and the output form of the image D / A circuit 6 is an S-video signal, a composite signal,
One or more of an RGB signal and a component signal.

The digital watermark added to the data recorded on the DVD 1 (not added in some cases) is an image that cannot be visually recognized.
If it is voice, it must be inaudible. In the case of an image, for example, a specific numbering system, an image such as an illustration, a logo mark of a manufacturer, or a country-specific ID may be used.

Further, the ID code may be generated (generated) by using a uniform random generator. At this time, it is necessary to pay attention to uniform random generation such that the same number is not stochastically produced in mass production. It is desirable to use a vessel.

In this case, the copy protection data generated at the first time and the copy protection data at the second time need to be stored in the non-volatile memory, respectively. It is necessary to verify the copy protection data that has been set.

By doing so, even if there are several identical data reproducing apparatuses, a disk reproduced and copied by one apparatus cannot be reproduced by another data reproducing apparatus.

Now, in the read signal obtained by the data recorded on the DVD 1 by the signal processing circuit 2 and the decoder circuit 3, the presence / absence of the digital watermark data is detected by the digital watermark detection circuit 8 and it is not present. Is detected, the copy protection data including ID code data indicating that the copy is the first copy is added, and is output as a reproduction signal (the above-described four-system output).

On the other hand, when the digital watermark detection circuit 8 detects the digital watermark data having the ID code indicating the first copy in the read signal, the ID code data indicating the second copy is obtained. Are output as a reproduction signal (the above-described four-system output).

On the other hand, when the digital watermark detection circuit 8 detects digital watermark data having an ID code indicating that the read signal is a second copy in the read signal, it is prohibited to output the read signal as a reproduction signal. Is done. At this time, it is desirable to display by a proper means in the data reproducing apparatus that "the mounted disc cannot be reproduced because it is the second copy".

Next, another embodiment of the present invention will be described with reference to FIG. FIG. 2 is a block circuit diagram of a data reproducing apparatus with a digital watermark function according to another embodiment of the present invention. An interface circuit 12, a decoder circuit 13, and a digital watermark detection circuit conforming to the IEEE 1394 standard are provided along a transmission path of a digital bus. 14, an electronic watermark generation circuit 15, an encoder circuit 16, and an interface circuit 17 of the IEEE 1394 standard are interposed, and these are controlled by a microprocessor 18 in a complex manner.

When the digital watermark detection circuit 14 finds foreign digital watermark data in the read signal, control is performed so that the encoder circuit 16 does not perform encoding to delete the data from the digital bus. .

If no digital watermark data is detected by the digital watermark detection circuit 14, the digital watermark data is output to the digital bus with copy protection data consisting of ID code data indicating that the digital copy is the first copy.

On the other hand, the digital watermark detection circuit 14
When digital watermark data having an ID code indicating a first copy is detected from the read signal, copy protection data including ID code data indicating a second copy is added to the digital signal, and the read signal is transmitted to a digital bus. Is output.

On the other hand, the digital watermark detection circuit 14
When digital watermark data including an ID code indicating a second copy is detected in the read signal, output of the read signal to the digital bus as a reproduction signal is prohibited.

The data reproducing apparatus with a digital watermark function according to the above-mentioned two embodiments adds digital watermark data to a normal image or audio signal, but scrambles the normal image or audio signal. The signal may be used as digital watermark data.

For embedding digital watermark data, for example, in the case of image data, an ID code generated the first time is embedded in the first frame of the image data, and an ID code generated second time is embedded in the second frame. (In addition to the frame, for example, 1 field, 2 fields, etc.), in the case of audio data, the ID code generated at the first time is embedded in the L channel data, May be embedded in the R channel data or vice versa, and may be divided by time, for example, the first and second seconds.

[0041]

As is apparent from the above description, according to the data reproducing apparatus with a digital watermark function of the present invention, the digital watermark detecting means for detecting the digital watermark data included in the read signal read from the recording medium. And output control means for adding copy protection data to the read signal based on the digital watermark data detected by the digital watermark detection means and outputting the read signal as a reproduction signal.
Since a new signal is added or deformed to a portion other than the image signal area, the image reproduced by the general TV monitor device does not deteriorate.

The embedding of the digital watermark data is performed according to I
Due to the inclusion of the D code, it is extremely difficult for the user to read the technical contents, and it is almost impossible to release the copy prohibition.

Furthermore, digital copying only once (one generation) can be permitted, copying twice (two generations) can be prevented, reproduction is permitted only on the own device, and reproduction on other devices is permitted. Reproduction can also be prohibited.

The present invention can be applied to all types of recording media regardless of the type of recording medium. It can also be used to prevent copy of digital data that does not exist in the source data. Of course, when there is digital watermark data of another system, priority can be given.

Therefore, it is possible to provide a data reproducing apparatus with a digital watermark function which can prevent digital watermark data for copy protection from being easily released and can correspond to audio digital data, image digital data and the like. .

[Brief description of the drawings]

FIG. 1 is a block circuit diagram of a data reproducing apparatus with a digital watermark function according to an embodiment of the present invention.

FIG. 2 is a block circuit diagram of a data reproducing apparatus with a digital watermark function according to another embodiment of the present invention.

FIG. 3 is a block circuit diagram showing an example of a conventional data reproducing apparatus with a digital watermark function.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 DVD 2 Signal processing circuit 3,13 Decoder circuit 4 D / A circuit for audio 6 D / A circuit for image 8,14 Digital watermark detection circuit 9,15 Digital watermark generation circuit 10,12,17 Interface circuit 11,18 Micro Processor 16 Encoder circuit

Claims (6)

[Claims] An electronic watermark function capable of outputting a read signal read from a recording medium recorded with image data and / or audio data added with electronic watermark data or recorded without adding the electronic watermark data as a reproduction signal. In the data reproducing apparatus, a digital watermark detecting means for detecting digital watermark data included in the read signal read from the recording medium; and a digital watermark detecting means for detecting the digital watermark data based on the digital watermark data detected by the digital watermark detecting means. An output control means capable of adding copy protection data and outputting the reproduced signal as a reproduction signal, comprising: a data reproduction device with a digital watermark function. 2. The apparatus according to claim 1, wherein said output control means includes means for outputting ID code data indicating the first copy when said digital watermark detection means detects that said digital watermark data is not present in said read signal. 2. The data reproduction apparatus with a digital watermark function according to claim 1, wherein the copy protection data is added to the read signal and output as a reproduction signal. 3. When the digital watermark detection means detects digital watermark data, which is an ID code indicating that the read signal is a second copy, in the read signal, the output control means converts the read signal to a reproduction signal. 2. The data reproducing apparatus with a digital watermark function according to claim 1, wherein output is prohibited. 4. The apparatus according to claim 1, wherein said output control means includes means for outputting ID code data indicating that the digital signal is a first copy when the digital watermark detection means detects that the digital watermark data is not present in the read signal. Is added to the read signal and output as a reproduction signal, and the digital watermark data including the ID code indicating that the copy is the first copy is detected by the digital watermark detection means. Sometimes the ID of the second copy
Copy protection data consisting of code data is added to the read signal and output as a reproduction signal, and digital watermark data consisting of an ID code indicating that the read signal is a second copy is detected by the digital watermark detection means. 2. The data reproducing apparatus with a digital watermark function according to claim 1, wherein when the reading is performed, outputting the read signal as a reproducing signal is prohibited. 5. The digital watermarking function according to claim 1, wherein the output control means is configured to output the reproduction signal in a digital signal form to a digital bus. Data playback device. 6. The data reproduction with a digital watermark function according to claim 1, wherein the output control means is configured to output the reproduction signal in an analog signal form. apparatus.