JP2000196861A - Method and device for signal processing, and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a signal processing device which can specify a signal processing device, where an output signal is processed, from this output signal. SOLUTION: Audio data S9 is subjected to band division in a PQF 11, gain control in gain controllers 121 to 124 and an MDCT processing in MDCT processors 131 to 134 to generate DCT coefficients, and these DCT coefficients are padded with electronic watermark information which is outputted from an electronic watermark information generator 14 and is used to specify a receiver of supply of an ATRAC2 encoder 10. Thereafter, these DCT coefficients are quantized by a quantizer 17 and are encoded by a Huffman encoder 18 and are outputted as audio data S10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal processing apparatus and a signal processing method, and a recording medium in which a processing procedure using the signal processing method is recorded in a computer-readable manner.

[0002]

2. Description of the Related Art There are many processing methods and apparatuses for processing digital content signals which are subject to intellectual property rights. A person who wishes to use such a processing method or apparatus may, for example, establish a contract with an intellectual property right holder or the like, and then obtain software or processing using the processing method from the intellectual property right holder or the like. Equipment may be supplied.

In this case, the intellectual property right holder usually prohibits the contractor from copying or copying the supplied software or processing device without permission to a third party.

[0004]

However, for example, when a contractor ignores a contract with an intellectual property right holder,
When a third party is provided with a copy of software related to the contract or a copy of the processing device, the software or the processing device itself hardly leaks to the outside, so it is difficult to find an unauthorized user. There is a problem that there is. If the intellectual property right holder has contracted with many persons, for example, a third party who has not made a contract holds a copy or copy of software using a processing method related to the intellectual property right. Even if it is discovered that it is difficult to identify from whom the copy or copy has been leaked from many contractors, it is difficult to prove breach of contract There is.

[0005] The present invention has been made in view of the above-mentioned problems of the prior art. For example, when a signal processing is subject to a contract, a signal processing apparatus, a method thereof, and a recording method capable of easily specifying a violator of the contract. It is intended to provide a medium.

[0006]

In order to solve the above-mentioned problems of the prior art and achieve the above-mentioned object, a signal processing apparatus according to a first aspect of the present invention performs predetermined signal processing on an original signal. A signal processing device that performs the signal processing on the original signal, and digital watermark information indicating that the signal processing has been performed by the signal processing device, in the output signal. Information embedding means.

In the signal processing device according to the first aspect of the present invention, the digital watermark information preferably includes identification information assigned so as to uniquely identify the signal processing device.

In the signal processing device according to the first aspect of the present invention, preferably, the digital watermark information includes information indicating a version of the signal processing device.

In the signal processing device according to the first aspect of the present invention, preferably, the digital watermark information includes information for specifying a person who supplies the signal processing device.

In the signal processing device according to the first aspect of the present invention, preferably, the digital watermark information includes information for specifying a person who has been supplied with the signal processing device.

Further, a signal processing method according to a first aspect of the present invention is a signal processing method for performing predetermined signal processing on an original signal to generate an output signal, wherein the signal processing is performed in the signal processing method. Is included in the output signal.

A recording medium according to a first aspect of the present invention includes:
A procedure for performing signal processing on the original signal and a procedure for including digital watermark information indicating that the signal processing has been performed in the output signal are recorded in a computer-readable manner.

A signal processing device according to a second aspect of the present invention has information detecting means for detecting, from the signal, digital watermark information including information for specifying the signal processing device on which the signal has been processed.

In a signal processing method according to a second aspect of the present invention, digital watermark information including information for specifying a signal processing method in which a signal has been processed is detected from the signal.

A recording medium according to a second aspect of the present invention includes:
A procedure for detecting, from the signal, digital watermark information including information for specifying a recording medium on which the procedure in which the signal has been processed is recorded is recorded so as to be readable by a computer.

[0016]

Embodiments of the present invention will be described below. The signal processing method and the signal processing apparatus according to the present embodiment are configured to output a signal or a digital watermark used to identify a program or a signal processing apparatus that has performed the signal processing on a signal generated and output by performing processing using the signal processing method and the signal processing apparatus. (Digital W
atermark) Embed information. Here, the processing content in the signal processing device is not particularly limited as long as it generates a signal. In the embodiment described below, audio processing, image processing, and the like will be described as examples of signal processing.

Audio signals and image signals are often generated by performing various processes protected by intellectual property rights and the like. For example, as shown in FIG. 1, after an audio signal and an image signal are generated by the signal generation device 2, they are processed and transmitted by the editing effect device 3, the band compression device 4, the transmission device 5, and the like, respectively. May be subjected to reception processing.

In this case, the signal generation device 2, the editing effect device 3, the band compression device 4, the transmission device 5, the reception device 6, and the like perform various processes protected by intellectual property rights. For example, as the signal generation device 2, for example, a microphone, a video camera, a video camera, or the like is used. In the editing effect device 3, for example, mixer processing, effector processing, and the like are performed.

In the band compression device 4, for example, the AT
RAC (Adaptive TRansform Acoustic Coding), MPE
G (Moving Picture Experts Group), Dolby, Wavelet transform, JPEG (Joint Photographic Experts
Group). In the transmitting device 5,
For example, OFDM (Orthogonal Frequency Division Mul
Modulation processing such as tiplexing, VSB (Vestigial SideBand), and trellis is performed. In the receiving device 6,
Viterbi, PRML (Partial Response Maximum Likeliho
od) and decompression processing.

First Embodiment In this embodiment, an ATRAC2 encoder will be described as an example. The ATRAC2 encoder is an ATRAC2 encoder obtained by improving the ATRAC scheme. Where A
The TRAC system is 44.1 kHz, 16 bits / sa
audio signal (70
5.6 kbps / ch) to about 128 kbps / ch without causing any substantial deterioration in hearing.
The ATRAC2 system uses the ATRAC system at 128 kbps at 64 kbps / ch while encoding independently for each channel.
It achieves a sound quality comparable to bps / ch.

FIG. 2 is a configuration diagram of the ATRAC2 encoder 10 of the present embodiment. As shown in FIG.
The C2 encoder 10 is a PQF (Polyphase Quadrature).
Filter) 11, a gain controller 12 ₁ ~12 _4, MDCT
(Modified Discrete Cosine Transform) Processor 13 ₁ ~
13 _4, the electronic watermark information generator 14, information embedder 1
5, a psycho model processor 16, a quantizer 17, and a Huffman encoder 18, and are constituted by, for example, a single semiconductor chip.

The PQF 11 is a band division filter that divides the input original audio signal S9 into four bands of equal bandwidth, and the samples obtained thereby are thinned out at a rate of 1/4 in each band. PQF11
Are stored in the register every 1024 samples.

The gain controller 12 ₁ to 12 ₄ reads the 1024 samples stored in the register, PQF
Gain control is performed for each of the bands divided by 11 using a gain control function adaptively configured according to the degree of amplitude change.

The MDCT processors 13 _{1 to} 13 ₄ receive 1024 input signals from the gain controllers 12 _{1 to} 12 ₄ , respectively.
The sample signal is converted into spectral coefficients using a fixed conversion block length.

The digital watermark information generator 14 is, for example, as shown in FIG.
Information specifying the ATRAC2 encoder 10 such as the serial number of the product shown in FIG. 3A. If the ATRAC2 encoder 10 is related to an intellectual property right, for example, FIG.
FIG. 3B shows information for identifying a person who has made a contract with the intellectual property right holder, such as the name and identification number of the person.
An electronic device including at least one of information for specifying the version of the ATRAC2 encoder 10, information for specifying the person who has been supplied with the ATRAC2 encoder 10, and information for specifying the supplier of the ATRAC2 encoder 10 as shown in FIG. The watermark information is sent to the psycho model processor 1
6 to the information embedder 15 based on the control.
The electronic watermark information includes, for example, ATR
Information such as the date when the process was performed using the AC2 encoder 10 may be included.

The information embedding unit 15, an electronic watermark information input from the electronic watermark information generator 14 embeds be reflected in the spectral coefficients input from MDCT processor _131-134. The process of embedding the digital watermark information cannot be controlled from outside the semiconductor chip, and the digital watermark information is automatically embedded regardless of the user's intention.

The psycho model processor 16 has a psychoacoustics (P
Based on the sychoacoustic model, the information embedding unit 15 is controlled by controlling the information embedding unit 15 so that it is hardly perceived auditorily and is not deleted in the quantization process in the quantizer 17.
Embedding electronic watermark information in the spectral coefficient input from the DCT processor _131-134. The psycho model processor 16 controls the quantization process of the quantizer 17 based on the psychoacoustic model.

Hereinafter, control of embedding of digital watermark information into spectral coefficients by the psycho model processor 16 will be described. There are various schemes for embedding digital watermark information. Here, the multicarrier scheme and the lower bit embedding scheme will be described as examples.

In the multicarrier system, first, FIG.
(A), the preselected one or more of a specific frequency component among the frequency components represented by the spectrum coefficients input from MDCT processor _131-134. Then, as shown in FIG. 4B, the information embedding unit 15 changes the selected frequency component to a spectrum coefficient so that the level of the selected frequency component becomes zero.

Then, as shown in FIG. 4C, the information embedding unit 15 replaces the level of the selected frequency component with a level corresponding to the digital watermark information input from the digital watermark information generator 14. Change the spectral coefficients. At this time, the digital watermark information can be embedded with almost no influence on the sound quality by increasing or decreasing the level to be replaced according to the level of the peripheral frequency component. Specifically, when embedding the logical value “1”, the level of the selected frequency component is made larger than the levels of the frequency components on both sides, and when embedding the logical value “0”, the selected frequency component is selected. The level of the frequency component is made smaller than the levels of the frequency components on both sides. The decoder compares the level of the selected frequency component with the levels of the frequency components on both sides of the selected frequency component,
Identify the logical value of the embedded digital watermark information.

Further, the lower bits embedded system, first, pre-selected one or more specific frequency components of the spectral coefficients input from MDCT processor _131-134. Then, when embedding the logical value “0”,
When all the lower-order bits of the frequency spectrum indicating the selected frequency component are set to the logical value “0” and the logical value “1” is embedded, at least one of the lower-order bits is set to the logical value “1”. . The decoder identifies the logical value of the embedded digital watermark information by identifying whether or not all lower-order bits of the selected frequency component have logical values “0”.

The quantizer 17 is a psycho model processor 16
, And quantizes the spectral coefficient embedded with the digital watermark information input from the Huffman encoder 18.

The Huffman encoder 18 Huffman-encodes the quantized spectral coefficients input from the quantizer 17 and stores them in a register, and then outputs them as a bit stream audio signal S10.

Hereinafter, the flow of processing in the ATRAC2 encoder 10 will be described. FIG.
5 is a flowchart for explaining a processing flow in the encoder 10. Step SP1: Original audio signal S9 is ATRAC
2 is taken into the encoder 10.

Step SP2: Original audio signal S9
Is stored in a register every 1024 samples after being divided into four bands of equal bandwidth in PQF11.

Step SP3: 1024 samples stored in the register are read out, and the gain controller 12 ₁ is read.
In 12 _4, for each band divided by PQF11, it is gain control using a gain control function that is configured to adaptively according to the degree of amplitude change.

Step SP4: Gain-controlled 102
Four samples are stored in each of the MDCT processors 1 for each band.
It is outputted to 3 _{1-13 4,} using the transform block length of the fixed, is transformed into spectral coefficients. The spectral coefficients are stored in a register.

Step SP5: In the information embedding unit 15, based on the control from the psycho model processor 16,
The level of the frequency component selected in advance is replaced with a level corresponding to the digital watermark information input from the digital watermark information generator 14.

Step SP6: In the information embedding unit 15, based on the control from the psycho model processor 16,
The level of the selected frequency component is scaled and corrected by the average of the levels on both sides. As a result, the digital watermark information is embedded. At this time, the digital watermark information to be embedded includes information for specifying the ATRAC2 encoder 10 and the name and identification number of a person who has contracted with the intellectual property right holder when the ATRAC2 encoder 10 relates to intellectual property rights. Information that identifies the person, ATR
Information for specifying the version of the AC2 encoder 10, A
At least one of information for specifying a person who has been supplied with the TRAC2 encoder 10 and information for specifying a supplier of the ATRAC2 encoder 10 is included.

Step SP 7: The spectral coefficient in which the digital watermark information is embedded is quantized by the quantizer 17 and then output to the Huffman encoder 18.

Step SP8: The quantized spectral coefficients are Huffman-coded by the Huffman encoder 18 and stored in a register.

Step SP9: The Huffman-coded spectral coefficients read from the register are output as a bit stream audio signal S10.

As described above, according to the ATRAC2 encoder 10, in the process of encoding the original audio signal S9 and generating the audio signal S10, the audio signal S10 contains the audio signal S10 regardless of the intention of the user of the ATRAC2 encoder 10. Information for automatically identifying the ATRAC2 encoder 10; information for identifying the ATRAC2 encoder 10, such as the name and identification number of a person who has contracted with the intellectual property right holder when the ATRAC2 encoder 10 relates to intellectual property rights; Digital watermark information including at least one piece of information for specifying the version of the ATRAC2 encoder 10 is embedded.

Therefore, by decoding the audio signal S10 with a decoder and identifying the digital watermark information, it can be specified that the audio signal S10 has been generated using the ATRAC2 encoder 10. Therefore, for example, the intellectual property right holder may give the contractor the ATRAC2 encoder 1 on the condition that it is not copied or lent to a third party.
0, the digital watermark information embedded in the audio signal leaked from a person other than the contractor
If it is known that the AC2 encoder 10 is specified, it can be easily proved that the contractor has breached the contract. In other words, even if the ATRAC2 encoder 10 itself has not leaked to the outside, the audio signal is determined to be AT AT from the digital watermark information included in the audio signal.
It can be easily known that the data is generated using the RAC2 encoder 10.

Further, since the above-mentioned digital watermark information includes information which can specify individual contractors, even if there are many contractors, the contractor who has breached the contract can be easily specified.

As the digital watermark information described above, A
In the case where the information specifying the manufacturer of the TRAC2 encoder 10 is used, a person who has been supplied with the audio signal S10 determines, based on the digital watermark information embedded in the audio signal S10, the supplier (manufacturer of the ATRAC2 encoder 10). Person) can be identified. Therefore, it is possible to apply to the supplier of the ATRAC2 encoder 10 for permission to use it.

Second Embodiment In this embodiment, an MPEG encoder will be described. FIG. 6 is a configuration diagram of the MPEG encoder 40.
As shown in FIG. 6, the MPEG encoder 40 includes a block divider 41, a DCT processor 42, a linear quantizer 43,
It has a digital watermark information generator 44 and a Huffman encoder 45, and is composed of a single semiconductor chip.

The block divider 41 divides the input original image signal S39 into macroblocks of 8 × 8 pixels and outputs the resultant to the DCT processor 42.

The DCT processor 42 includes a block divider 41
Then, DCT transform coefficients generated by performing DCT processing are output to the linear quantizer 43 in units of macroblocks input from. The linear quantizer 43 linearly quantizes the DCT transform coefficient input from the DCT processor 42, and according to the digital watermark information input from the digital watermark information generator 44, converts the DCT Digital watermark information is embedded by changing the value within a range that hardly affects the image quality. Note that a wavelet transform processor may be used instead of the DCT processor 42.

The digital watermark information generator 44 includes information for specifying the MPEG encoder 40, the MPEG encoder 40
Is related to intellectual property rights, information specifying the person who has contracted with the intellectual property right, such as the name and identification number, information specifying the version of the MPEG encoder 40, supply of the MPEG encoder 40 The digital watermark information including at least one of the information specifying the recipient and the information specifying the supplier of the MPEG encoder 40 is output to the linear quantizer 43. In addition, the digital watermark information may further include information such as a date on which the processing was performed using the MPEG encoder 40, for example. The embedding of digital watermark information cannot be controlled from outside the semiconductor chip.

The Huffman encoder 45 includes a linear quantizer 4
After the quantized DCT transform coefficient input from No. 3 is Huffman-coded and stored in a register, it is output as a bit stream image signal S40.

Hereinafter, the MPEG encoder 40 shown in FIG.
Will be described. FIG.
5 is a flowchart for explaining the flow of processing in a G encoder 40. Step SP11: If the original image signal S39 is MPEG
It is taken into the encoder 40. Step SP12: The original image signal S39 is divided by the block divider 41 into macroblocks of 8 × 8 pixels, and then output to the DCT processor.

Step SP13: In the DCT processor 42, DCT processing is performed for each macroblock input from the block divider 41, and the DCT transform coefficients generated by the DCT processing are output to the linear quantizer 43. You. (3) Step SP14: In the linear quantizer 43, the DCT
When the DCT transform coefficient input from the processor 42 is linearly quantized, the value of the DCT transform coefficient of the middle frequency has almost no effect on the image quality according to the digital watermark information input from the digital watermark information generator 44. Digital watermark information is embedded while being changed within a range not provided. At this time, the electronic watermark information includes information for specifying the MPEG encoder 40, MPEG
When the encoder 40 is related to an intellectual property right, information for specifying the person who has contracted with the intellectual property right, such as the name and identification number, information for specifying the version of the MPEG encoder 40, and the MPEG encoder 40 And at least one of information for specifying a supplier of the MPEG encoder 40 and information for specifying a supplier of the MPEG encoder 40.

Step SP15: Huffman encoder 4
5, the quantized DC from the linear quantizer 43
The T-transform coefficients are Huffman-coded and stored in a register.

Step SP16: The Huffman-coded DCT transform coefficient read from the register is output as a bit stream image signal S40.

As described above, according to the MPEG encoder 40, similarly to the ATRAC2 encoder 10 of the above-described first embodiment, the contractor who has breached the contract can be easily specified.

The present invention is not limited to the above embodiment. For example, in the above-described MPEG encoder 40 of the first embodiment, the case where digital watermark information is embedded when the DCT transform coefficient is linearly quantized has been exemplified. However, after performing DCT processing for each macroblock, the DCT transform coefficient The electronic watermark information may be embedded by spectrum spreading. When detecting the digital watermark information from the image signal, the digital watermark information is extracted by calculating the difference between the frequency components of the original image and the image in which the digital watermark information is embedded. Then, a correlation between the registered digital watermark information and the extracted digital watermark information is calculated to specify the digital watermark information.

In the above-described embodiment, the signal processing apparatus such as the ATRAC2 encoder 10 and the MPEG encoder 40 and the method therefor have been described as an example. However, in the present invention, for example, processing relating to intellectual property rights is performed by software. In this case, a computer-readable recording medium such as a CD-ROM, a DVD, or a floppy disk that records a description of a process for automatically embedding digital watermark information for specifying the software and a description of the process of the software. It may be.

In the above embodiment, ATRAC
In the case of embedding the digital watermark information in the process of the signal processing of the intellectual property rights such as IP and MPEG, for example, as shown in FIG. The information embedding device 20 is provided before the circuit 200.
1 and a digital watermark information generator 202 for embedding the digital watermark information in the original signal.
0 may be used for signal processing. Also, as shown in FIG. 9, the signal processing circuit 3 which is the subject of intellectual property
00, an information embedder 301 and a digital watermark information generator 302 are provided to convert the original signal into a signal processing circuit 300.
After the signal processing, the digital watermark information may be embedded to generate an output signal.

Hereinafter, a decoder for detecting digital watermark information from an audio signal generated by using the above-described encoder will be described. Third Embodiment In the present embodiment, an ATARC2 decoder that decodes the audio signal S10 generated using the ATRAC2 encoder 10 shown in FIG. 2 will be described.
FIG. 10 is a configuration diagram of the ATARC2 decoder 50.
As shown in FIG. 10, the ATARC2 decoder 50 includes a Huffman decoder 51, an inverse quantizer 52, an inverse MDCT processor 53, and a digital watermark information detector 54. The Huffman decoder 51 performs, for example, Huffman decoding on the audio signal S10 read from a recording medium such as an MD, stores the quantized spectral coefficients obtained by the Huffman decoding in a register, and then stores the inverse quantizer 52 in the register. Output to

The inverse quantizer 52 receives the quantized spectral coefficients from the Huffman decoder 51, inversely quantizes the quantized spectral coefficients, and performs inverse MDCT processing.
3 and the digital watermark information detector 54.

The inverse MDCT processor 53 includes an inverse quantizer 52
And performs inverse MDCT processing to transform the spectral coefficients input from the frequency domain into the time domain, and outputs an audio signal S50 which is a PCM signal obtained by the conversion.

The digital watermark information detector 54 uses, for example, the spectral coefficient input from the inverse quantizer 52 to determine the level of the frequency component predetermined at the time of encoding and the level of the frequency component on both sides of the frequency component. Is determined. If the level of the predetermined frequency component is higher, digital watermark information of logical value “1” is embedded, and if the level of the predetermined frequency component is lower, digital watermark information of logical value “0” is embedded. Judge as embedded. Also, the digital watermark information detector 54 uses, for example, the spectral coefficient input from the inverse quantizer 52, when the lower few bits of the spectral coefficient indicating a predetermined frequency component at the time of encoding are all “0”. It is determined that digital watermark information with a logical value “0” is embedded in the “.”, And otherwise, digital watermark information with a logical value “1” is embedded.

The digital watermark information detector 54 outputs the detected digital watermark information S58. Here, the digital watermark information S58 is, for example, the ATRAC2 encoder 1 shown in FIG. 2 such as the serial number of the product shown in FIG.
0 when the ATRAC2 encoder 10 is related to an intellectual property right. For example, the person or the identification number of a person who has contracted with the intellectual property right holder as shown in FIG. Among the information to be specified, for example, information for specifying the version of the ATRAC2 encoder 10 as shown in FIG. 3C, information for specifying the person who has been supplied with the ATRAC2 encoder 10, and information for specifying the supplier of the ATRAC2 encoder 10 It contains at least one piece of information.

Hereinafter, the flow of processing in the ATARC2 decoder 50 shown in FIG. 10 will be described. FIG.
11 is a flowchart for describing the flow of processing in the ATARC2 decoder 50 shown in FIG. Step SP1: Audio signal S10 is ATARC2
The data is taken into the decoder 50.

Step SP2: The audio signal S10 fetched in step SP1 is Huffman decoded in the Huffman decoder 51, and the quantized spectral coefficients obtained by the Huffman decoding are stored in a register. Then, the quantized spectral coefficients are read from the register and output to the inverse quantizer 52.

Step SP3: After the quantized spectral coefficients are inversely quantized by the inverse quantizer 52, they are output to the inverse MDCT processor 53 and the digital watermark information detector 54.

Step SP4: Digital watermark information detector 5
At 4, the digital watermark information is detected based on the spectral coefficient input from the inverse quantizer 52.

Step SP5: The digital watermark information S58G detected in step SP4 is output.

As described above, according to the ATARC2 decoder 50, the ATRAC2 encoder 1 shown in FIG.
The digital watermark information S58 can be detected from the audio signal S10 generated using 0. as a result,
According to the ATARC2 decoder 50, the audio signal S
10 can be specified by the ATRAC2 encoder 10 shown in FIG. 2, and the effects described above in the first embodiment can be obtained.

The present invention is not limited to the above embodiment. For example, when inputting an audio signal which is a PCM signal in which digital watermark information is embedded, for example, a digital watermark information detecting device having a configuration shown in FIG. 12 may be used. As shown in FIG. 12, the digital watermark information detecting device 60
Has an A / D converter 61, a switch 62, an MDCT processor 63, and a digital watermark information detector 64. When the digital watermark information detection device 60 receives an audio signal S70 which is a PCM signal, the audio signal S70 is output to the MDCT processor 63 via the switch 62. On the other hand, when an analog audio signal S71 is input, the audio signal S70 is converted into a digital audio signal by the A / D converter 61, and then output to the MDCT processor 63 via the switch 62.

Then, in the MDCT processor 63, the audio signal is frequency-converted, and the resulting spectral coefficient is output to the digital watermark information detector 64.
Then, in the digital watermark information detector 64, the digital watermark information S60 is detected by the same method as the digital watermark information detector 54 of FIG. 10 described above.

Further, the present invention may be a recording medium such as a CD-ROM or a DVD in which the procedure shown in FIG. 11 is stored.

[0074]

As described above, according to the signal processing apparatus, the method, and the recording medium of the present invention, based on the output signal, the output signal controls the signal processing apparatus, the method, and the recording medium, respectively. Can be used to identify what has been processed. Further, according to the signal processing device, the method, and the recording medium of the present invention, by detecting digital watermark information included in the signal, the signal processing device, the method, and the recording medium used for processing the signal can be used. Each can be specified.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining various signal processing devices to which the present invention is applied.

FIG. 2 shows ATRAC2 according to the first embodiment of the present invention.
It is a block diagram of an encoder.

FIG. 3 is a diagram for explaining an example of digital watermark information;

FIG. 4 is a diagram for explaining a multi-carrier method, which is one of the techniques for embedding digital watermark information.

FIG. 5 is a flowchart for explaining a processing flow in the ATRAC2 encoder shown in FIG. 1;

FIG. 6 is a configuration diagram of an MPEG encoder according to a second embodiment of the present invention.

FIG. 7 is a flowchart for explaining the flow of processing in the MPEG encoder shown in FIG. 6;

FIG. 8 is a configuration diagram in a case where digital watermark information is embedded at a stage prior to a signal processing circuit.

FIG. 9 is a configuration diagram in a case where digital watermark information is embedded in a subsequent stage of the signal processing circuit.

FIG. 10 shows an ATAR according to a third embodiment of the present invention.
It is a block diagram of a C2 decoder.

FIG. 11 is a flowchart for explaining a processing flow in the ATARC2 decoder shown in FIG. 10;

FIG. 12 is a configuration diagram of a decoder according to another embodiment of the present invention.

[Explanation of symbols]

10 ATRAC2 encoder, 11 PQF, 12 ₁
... 12 ₄ ... gain controller, 13 _{1 to} 13 ₄ ... MDCT processor, 14 ... digital watermark information generator, 15 ... information embedding unit, 16 ... psycho model processor, 17 ... quantizer, 1
8 ... Huffman encoder, 40 ... MPEG encoder, 4
DESCRIPTION OF SYMBOLS 1 ... Block divider, 42 ... DCT processor, 43 ... Linear quantizer, 44 ... Digital watermark information generator, 45 ... Huffman encoder, 50 ... ATARC2 decoder, 51 ... Huffman decoder, 52 ... Inverse quantization 53, inverse MDCT processor, 54, digital watermark information detector, 60, digital watermark information detector, 61, A / D converter, 62, switch, 6
3 ... MDCT processor, 64 ... Digital watermark information detector

Claims (28)

[Claims] 1. A signal processing device that performs predetermined signal processing on an original signal to generate an output signal, a signal processing unit that performs signal processing on the original signal, and indicates that the signal processing has been performed by the signal processing device. A signal processing device having information embedding means for including digital watermark information in the output signal. 2. The signal processing device according to claim 1, wherein the digital watermark information includes identification information assigned to uniquely identify the signal processing device. 3. The signal processing device according to claim 1, wherein the digital watermark information includes information indicating a version of the signal processing device. 4. The signal processing device according to claim 1, wherein the digital watermark information includes information for specifying a person who supplies the signal processing device. 5. The signal processing device according to claim 1, wherein the digital watermark information includes information for specifying a person who has been supplied with the signal processing device. 6. The signal processing apparatus according to claim 1, wherein said information embedding means includes said digital watermark information in said original data in a process of processing said original data by said signal processing means. 7. The signal processing apparatus according to claim 1, wherein said original signal is an audio signal, and said signal processing means compresses said audio signal. 8. A band division filter that divides a first audio signal into a plurality of bands having substantially equal bandwidths, and generates a spectrum coefficient by orthogonally transforming the band-divided audio signal from a time domain to a frequency domain. The signal processing apparatus according to claim 7, further comprising an orthogonal transform unit, wherein the information embedding unit includes the digital watermark information in the generated spectral coefficient. 9. A signal according to claim 8, wherein said information embedding means determines a spectrum coefficient of a frequency component previously selected as a frequency component in which said digital watermark information is embedded, to a value corresponding to the digital watermark information to be embedded. Processing equipment. 10. The information embedding means according to claim 9, wherein a magnitude relationship between the selected frequency component and frequency components on both sides of the selected frequency component is determined according to the digital watermark information to be embedded. Signal processing device. 11. The signal processing apparatus according to claim 8, further comprising: a quantizing means for quantizing the spectral coefficient in which the digital watermark information is embedded; and an encoding means for encoding the quantized spectral coefficient. apparatus. 12. The signal processing apparatus according to claim 1, wherein the information embedding means includes the digital watermark information in the original data before processing the original data by the signal processing means. 13. The information embedding means, after processing the original data by the signal processing means, includes the digital watermark information in a signal obtained by the processing.
The signal processing device according to claim 1. 14. The signal processing device according to claim 1, wherein said predetermined processing is an image compression processing. 15. A signal processing method for performing predetermined signal processing on an original signal to generate an output signal, wherein the output signal includes digital watermark information indicating that the signal has been processed by the signal processing method. Method. 16. The signal processing method according to claim 15, wherein the digital watermark information includes identification information assigned so as to uniquely identify software using the signal processing method. 17. The signal processing method according to claim 15, wherein the digital watermark information includes information indicating a version of software using the signal processing method. 18. A recording medium in which a procedure for signal processing of an original signal and a procedure for including digital watermark information indicating that the signal processing has been performed in an output signal are readable by a computer. 19. The recording medium according to claim 18, wherein said digital watermark information includes identification information assigned so as to uniquely identify said recording medium. 20. A signal processing device having information detection means for detecting, from the signal, digital watermark information including information for specifying the signal processing device on which the signal has been processed. 21. The signal processing apparatus according to claim 20, wherein the digital watermark information includes identification information assigned so as to uniquely identify the signal processing apparatus. 22. The signal processing device according to claim 20, wherein the digital watermark information includes information indicating a version of the signal processing device. 23. The signal processing device according to claim 20, wherein the digital watermark information includes information for specifying a person who supplies the signal processing device. 24. The signal processing apparatus according to claim 20, wherein the digital watermark information includes information for specifying a person who has been supplied with the signal processing apparatus. 25. The signal according to claim 1, wherein said signal indicates a spectrum coefficient indicating a frequency component, and said information detecting means converts said digital watermark information based on a value of a spectrum coefficient of a predetermined frequency component among spectrum coefficients indicated by said signal. 21. The signal processing device according to claim 20, which detects. 26. An orthogonal transforming means for orthogonally transforming the signal from a time domain to a frequency domain to generate spectral coefficients, wherein the information detecting means comprises a predetermined frequency among the generated spectral coefficients. 21. The signal processing device according to claim 20, wherein the digital watermark information is detected based on a value of a spectral coefficient of the component. 27. A signal processing method for detecting, from a signal, digital watermark information including information for specifying a signal processing method on which the signal has been processed. 28. A recording medium on which a procedure for detecting, from a signal, digital watermark information including information for specifying a recording medium on which a procedure for processing a signal is recorded is read by a computer.