JPH04137900A - Signal processing unit and acoustic reproducing device - Google Patents

Abstract

PURPOSE:To adjust the characteristic of a reproduced sound in matching with an acoustic characteristic specific to a listener by providing a characteristic flat means cancelling the acoustic characteristic component of recording environment and a characteristic conversion means converting the characteristic into a listening sense acoustic characteristic of listening environment specific to the listener to the equipment. CONSTITUTION:The characteristic of a known transfer function of a dummy head or the like included in a reproduction signal is made flat by a characteristic by a characteristic flat means 101 in the case of reproducing a recording recorded by the dummy head or the like. Then an impulse sound radiates from a speaker and is picked up by a microphone loaded to both ears of the listener and a transfer function based on a shape of the head and ear shell specific to the listener or the like is extracted and the characteristic of the reproduction signal processed flat is converted into the listening sense acoustic characteristic specific to the listener by the characteristic conversion means 102. Thus, the characteristic of the reproduction sound in matching with the acoustic characteristic based on the shape of the head and ear shell specific to the listener or the like and the stereophonic sense and the presence of the reproduced sound are further improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a reproduced signal processing device and an audio reproduction device, and in particular, to processing and reproduction of a binaural reproduced signal obtained by reproducing a binaurally recorded audio signal. The present invention relates to a suitable signal processing device and sound reproduction device.

[Conventional technology]

Conventionally, a binaural recording and playback system has been known as one of the sound playback systems that play back sound three-dimensionally. A binaural recording and playback system captures sound from a sound source and records it on a recording medium using microphones installed near both ears of a dummy head, which is a human head model. This is done using headphones worn in the ears. According to this system, it is possible to directly radiate the left channel sound to the left ear and the right channel sound to the right ear.
Problems were that the sound image was difficult to localize in front of the listener, and that the headphones felt oppressive and unnatural when worn on the head.

For this reason, you can use speakers without using headphones.
A surround recording and playback system is known as an attempt to reproduce sound three-dimensionally. A surround recording and playback system takes in sound from a sound source using a microphone with two or more channels (for example, four channels), encodes it into two channels through signal processing, records it on a recording medium, and decodes it back into four channels during playback. It is played back from a speaker. According to this system, direct sound is mainly emitted from the two speakers in front of the listener, and indirect sound, reflected sound, etc. are also emitted from the two speakers on the back of the listener, making it possible to reproduce sound three-dimensionally. It is. However, there have been problems in that the system becomes complicated, such as requiring a large number of speakers, and that depending on the encoding and decoding methods, it can leave an unnatural or artificial feel.

[Problem to be solved by the invention]

Recently, as an example of a new stereophonic sound reproduction system, the 9th
A binaural surround recording and playback system as shown in the figure has been proposed. In this system, the recording system includes microphones MC, MC, and amplifier A
A2, an encoder EN, and a recording device RE. The sound from the sound source SS is converted into an electric signal by the microphone MC attached to the dummy head DH, amplified to an appropriate level by the amplifier A, and encoded by the encoder EN. Record on ff1RE or recording medium M. The playback system includes a playback device PL, amplifiers A 1 , A 2 , and speakers SP 2 , SP. During playback, the signal recorded on the recording medium M is read out by the playback device PL, and after being amplified to an appropriate level using the amplifiers A and A, the signal is sent to the speakers SP and SP.
2 is emitted as sound to the listener LS. in this case,
When a so-called crosstalk phenomenon occurs, in which the left channel sound is heard by the right ear, and the right channel sound is also heard by the left ear, the three-dimensional effect is lost, so processing is performed to cancel the left and right crosstalk acoustic components. Function/encoder EN
is added to. Is there an advantage to this system because it combines the advantages of the first two? Because the shape and dimensions of the head, auricle, etc. of the dummy head DH are different from those of the listener LS, the three-dimensionality and realism of the sound are affected. However, a problem remained.

Therefore, if the characteristics of the reproduced sound can be adjusted in accordance with the acoustic characteristics based on the listener's unique head shape, pinna shape, etc., it is possible to further improve the three-dimensional effect and sense of presence of the reproduced sound.

An object of the present invention is to provide a reproduced signal processing device and a sound reproduction system that can adjust the characteristics of reproduced sound in accordance with the acoustic characteristics based on the listener's unique head shape, auricle shape, etc.

[Means to solve the problem]

In order to solve the above problem, the invention according to claim 1
It is configured as shown in the figure.

In FIG. 1, this signal processing device 103 is a signal processing device that processes a recording signal that has been binaurally recorded, and has a characteristic that eliminates the acoustic characteristic component of the recording environment during binocular recording that is included in the playback signal S of the recorded signal. It includes a flattening means 101 and a characteristic converting means 102 that converts the characteristics of the flattened reproduced signal S into auditory-acoustic characteristics of a listening environment specific to the listener.

The invention according to claim 2 is the signal processing device according to claim 1, in which the acoustic characteristics of the recording environment are transfer functions of the recording environment, and the auditory acoustic characteristics of the listening environment specific to the listener are the transfer functions of the listening environment specific to the listener. is configured to be a transfer function.

According to a third aspect of the invention, in the signal processing apparatus according to the first or second aspect, the recording environment is configured to include a dummy head.

According to a fourth aspect of the invention, in the signal processing apparatus according to the first or second aspect, the recording environment is configured to include a human head.

According to a fifth aspect of the present invention, in the signal processing apparatus according to the first or second aspect, the recording environment is formed by signal processing.

The invention according to claim 6 provides a sound reproduction device for reproducing a recorded signal from a recording medium on which binaural recording is performed and outputting a reproduced signal, comprising an impulse signal generating means for generating an impulse signal, and converting the impulse signal into an impulse sound. an electroacoustic conversion means that emits the impulse sound into an acoustic space, and an apparatus 0 in both ears of the listener that collects the radiated impulse sound in the acoustic space, converts it into an electric signal S, and outputs it.
3. Acoustoelectric conversion means that can be attached and a reproduction signal S of a recorded signal
a characteristic flattening means 101 for erasing the acoustic characteristic components of the recording environment during binaural recording included in the binaural recording; reproduced signal S
and characteristic converting means 102 for converting and outputting the characteristics based on the acoustic characteristic data so as to match the acoustic characteristics of the listener's unique listening environment.

The invention according to claim 7 is the sound reproduction device according to claim 6, in which the acoustic characteristics of the recording environment are transfer functions of the recording environment, and the auditory acoustic characteristics of the listening environment specific to the listener are the transfer functions of the listening environment specific to the listener. is configured to be a transfer function.

According to an eighth aspect of the invention, in the sound reproduction apparatus according to the sixth or seventh aspect, the recording environment is configured to include a dummy head.

According to a ninth aspect of the invention, in the sound reproduction apparatus according to the sixth or seventh aspect, the recording environment is configured to include a human head.

According to a tenth aspect of the present invention, in the audio reproduction apparatus according to the sixth or seventh aspect, the recording environment is formed by signal processing.

The invention according to claim 11 provides a characteristic flattening means 1 for erasing the acoustic characteristic component of the recording environment at the time of pinochle recording, which is included in the playback signal S of the recorded signal, in the signal processing device 103 that processes the recorded signal recorded binaurally.
01, and characteristic converting means 102 which converts the characteristics of the flattened reproduction signal S into auditory-acoustic characteristics of the listening environment specific to the listener, and adds and outputs a component that cancels the crosstalk component to both ears of the listener. It is configured with and.

The invention according to claim 12 provides a sound reproduction device for reproducing a recorded signal from a recording medium on which binaural recording is performed and outputting a reproduced signal, comprising: an impulse signal generating means for generating an impulse signal; and an impulse signal generating means for converting the impulse signal into an impulse sound. an electroacoustic transducer that radiates into an acoustic space, and an acoustoelectric transducer that can be worn in both ears of a listener, which collects the radiated impulse sound in the acoustic space, converts it into an electrical signal S, and outputs it. and a reproduction signal S of the recorded signal.
a characteristic flattening means 101 for erasing the acoustic characteristic components of the recording environment during binaural recording included in the binaural recording; reproduced signal S
a characteristic converting means 102 that converts the characteristics of the listener based on the acoustic characteristic data to match the acoustic characteristics of the listener's unique listening environment, and adds and outputs a component that cancels the crosstalk component to both ears of the listener; It consists of:

The invention as set forth in claim 13 provides a signal processing device 103 that processes a recording signal that is binaurally recorded and has a component that cancels a crosstalk component added thereto. Characteristic flattening means 1 for eliminating acoustic characteristic components
01, and characteristic converting means 102 for converting the characteristics of the flattened reproduced signal S into auditory acoustic characteristics of the listening environment specific to the listener.

The invention according to claim 14 provides an impulse signal generation method for generating an impulse signal in a sound reproduction device that performs binaural recording and outputs a reproduced signal by reproducing a recorded signal from a recording medium to which a component for canceling a crosstalk component is added. an electroacoustic transducer that converts an impulse signal into an impulse sound and radiates it into an acoustic space; and a listener that collects the radiated impulse sound in the acoustic space, converts it into an electric signal S, and outputs it. Wearable in the ear +03 Wearable acoustoelectric conversion means and reproduction signal S of recorded signal
a characteristic flattening means 101 for erasing the acoustic characteristic components of the recording environment during binaural recording included in the binaural recording; reproduced signal S
and characteristic converting means 102 for converting and outputting the characteristics based on the acoustic characteristic data so as to match the acoustic characteristics of the listener's unique listening environment.

The invention according to claim 15 provides a signal processing device 103 that processes a recorded signal that is binaurally recorded and has a component that cancels a crosstalk component added thereto. Characteristic flattening means 1 for eliminating acoustic characteristic components
01, and characteristic converting means 102 which converts the characteristics of the flattened reproduction signal S into auditory-acoustic characteristics of the listening environment specific to the listener, and adds and outputs a component that cancels the crosstalk component to both ears of the listener. It is configured with and.

The invention according to claim 16 provides a sound reproduction device for reproducing a recorded signal from a recording medium that is binaurally recorded and to which a component that cancels out the component is added and outputs a reproduced signal, comprising: impulse signal generating means for generating an impulse signal; , an electroacoustic conversion means that converts an impulse sound into an impulse sound and radiates it into an acoustic space, and a listener's device which collects the radiated impulse sound in the acoustic space, converts it into an electric signal 5103, and outputs it. an acousto-electric conversion means that can be worn on both ears; a characteristic flattening means 101 for erasing acoustic characteristic components of the recording environment during binaural recording included in the reproduction signal 51oo of the recorded signal; and a converted electric signal S.
calculate acoustic characteristic data of the listener's unique listening environment based on the acoustic characteristic data, convert the characteristics of the flattened reproduced signal S to match the acoustic characteristics of the listener's unique listening environment based on the acoustic characteristic data, and , a characteristic conversion means for adding and outputting a component for canceling the crosstalk component to both ears of the listener.

The invention according to claim 17 provides a sound reproduction device for reproducing a recorded signal from a recording medium on which binaural recording is performed and outputting a reproduced signal, comprising an impulse signal generating means for generating an impulse signal, and a means for converting the impulse signal into an impulse sound. an electroacoustic transducer that radiates into an acoustic space, and an acoustoelectric transducer that can be worn in both ears of a listener and collects the radiated impulse sound in the acoustic space, converts it into an electric signal 5103, and outputs it. a characteristic conversion means for calculating acoustic characteristic data of a unique listening environment possessed by the listener based on the converted electric signal S, and adding and outputting a component that cancels a crosstalk component to both ears of the listener; .

The invention according to claim 18 provides an impulse signal generation method for generating an impulse signal in a sound reproduction device that performs binaural recording and outputs a reproduced signal by reproducing a recorded signal from a recording medium to which a component for canceling a crosstalk component is added. an electroacoustic transducer that converts an impulse signal into an impulse sound and radiates it into an acoustic space; and a listener that collects the radiated impulse sound in the acoustic space, converts it into an electric signal S, and outputs it. Apparatus 03 Wearable acoustoelectric conversion means and converted electric signal S
and characteristic converting means for calculating acoustic characteristic data of a listener's unique listening environment based on the above, and adding and outputting a component for canceling a crosstalk component to both ears of the listener.

[Operation] According to the invention as set forth in claim 1 having the above configuration, the signal processing device 10 that processes a high-naural recording signal.
In step 3, the characteristic flattening means 101 erases the acoustic characteristic component of the recording environment at the time of bytes+00 single recording, which is included in the reproduced signal S of the recorded signal. The characteristic conversion means 102 converts the flattened reproduction signal S
The characteristics of the listener are converted into auditory-acoustic characteristics of the listening environment unique to the listener.

According to the invention set forth in claim 2, in the signal processing device set forth in claim 1, the acoustic characteristics of the recording environment are transfer functions of the recording environment, and the auditory acoustic characteristics of the listening environment specific to the listener are the acoustic characteristics specific to the listener. Acts as a transfer function of the environment.

According to the third aspect of the present invention, in the signal processing apparatus according to the first or second aspect, a dummy head is included in the recording environment.

According to the fourth aspect of the present invention, in the signal processing device according to the first or second aspect, the recording environment includes a human head.

According to the invention set forth in claim 5, in the signal processing device set forth in claim 1 or 2, the recording environment is formed and operated by signal processing.

According to the invention as set forth in claim 6, in the sound reproduction device that reproduces a recorded signal from a recording medium on which binaural recording has been performed and outputs a reproduced signal, the impulse signal generating means generates an impulse signal. The electroacoustic conversion means converts the impulse signal into an impulse sound and radiates the impulse sound into an acoustic space.

The acousto-electric conversion means collects the radiated impulse sound in the acoustic space, converts it into an electric signal S and outputs it, and can be worn on both ears of the listener. The characteristic flattening means 101 erases the acoustic characteristic component of the recording environment at the time of binaural recording, which is included in the reproduced signal 51oo of the recorded signal. The characteristic conversion means 102 converts the converted electric signal S
The acoustic characteristic data of the listener's unique listening environment is calculated based on the acoustic characteristic data, and the characteristics of the flattened reproduced signal S are converted to match the acoustic characteristics of the listener's unique listening environment based on the acoustic characteristic data. Output.

According to the invention as set forth in claim 7, in the sound reproduction device as set forth in claim 6, the acoustic characteristics of the recording environment are transfer functions of the recording environment, and the auditory acoustic characteristics of the listening environment specific to the listener are the transfer functions of the listening environment specific to the listener. It acts as a transfer function of the listening environment.

According to the invention set forth in claim 8, in the sound reproduction device set forth in claim 6 or 7, the recording environment includes a tummy head.

According to the invention set forth in claim 9, in the sound reproduction device set forth in claim 6 or 7, the recording environment includes a human head.

According to the invention set forth in claim 10, in the sound reproduction device set forth in claim 6 or 7, the recording environment is formed and operated by signal processing.

According to the invention as set forth in claim 11, in the signal processing device for processing a recording signal recorded binaurally]03, the characteristic flattening means 101 is configured to adjust the characteristics of the recording environment at the time of the binaural recording, which is included in the reproduction signal S of the recording signal. Eliminates acoustic characteristic components.

The characteristic conversion means 102 converts the characteristics of the flattened reproduced signal S into auditory sound characteristics of the listening environment specific to the listener, adds a component that cancels the Talostok component to both ears of the listener, and outputs the resultant signal.

According to the twelfth aspect of the invention, in the sound reproduction device that reproduces a recorded signal from a recording medium on which binaural recording has been performed and outputs a reproduced signal, the impulse signal generating means generates an impulse signal.

The electroacoustic conversion means converts the impulse signal into an impulse sound and radiates it into an acoustic space. The acoustoelectric conversion means is
The radiated impulse sound is collected within the acoustic space,
It converts into an electrical signal S and outputs it, and can be worn in both ears of the listener. The characteristic flattening means 101 erases the acoustic characteristic component of the recording environment at the time of binaural recording, which is included in the reproduced signal S 1 of the recorded signal. Characteristic conversion means 102
calculates the acoustic characteristic data of the listener's unique listening environment based on the converted electrical signal S, and calculates the acoustic characteristic data of the listener's unique listening environment based on the acoustic characteristic data of the flattened reproduced signal S. It is converted to match the characteristics, and a component that cancels the crosstalk component to both ears of the listener is added and output.

According to the invention set forth in claim 13, in the signal processing device 103 that processes a recorded signal that is binaurally recorded and has a component that cancels out crosstalk components added, the characteristic flattening means 101 is configured to flatten the reproduced signal S of the recorded signal. Eliminates the included acoustic characteristic components of the recording environment during binaural recording. The characteristic conversion means 102 converts the characteristics of the flattened reproduced signal S into auditory-acoustic characteristics of the listening environment specific to the listener.

According to the fourteenth aspect of the present invention, in the sound reproduction device that outputs a reproduced signal by reproducing a recorded signal from a recording medium that is binaurally recorded and has a component that cancels a crosstalk component added, the impulse signal generating means comprises: Generate an impulse signal. The electroacoustic conversion means converts the impulse signal into an impulse sound and radiates the impulse sound into an acoustic space. The acousto-electric conversion means collects the radiated impulse sound in the acoustic space, converts it into an electric signal S and outputs it, and can be worn on both ears of the listener. The characteristic flattening means 101 erases the acoustic characteristic component of the recording environment at the time of pie-no-chill recording, which is included in the reproduced signal S 1 of the recorded signal. The characteristic conversion means 102 converts the converted electric signal S
Based on the acoustic characteristic data of the listener's unique listening environment, the characteristics of the flattened reproduced signal S are converted to match the acoustic characteristics of the listener's unique listening environment based on the acoustic characteristic data and output. do.

According to the invention set forth in claim 15, in the signal processing device 103 that processes a recording signal that is binaurally recorded and has a component that cancels out crosstalk components added thereto, the characteristic flattening means 101 converts the recorded signal into a reproduced signal S. Eliminates the included acoustic characteristic components of the recording environment during binaural recording. The characteristic conversion means 102 converts the characteristics of the flattened reproduced signal S into auditory-acoustic characteristics of the listening environment specific to the listener, adds a component that cancels the crosstalk component to both ears of the listener, and outputs the resultant signal.

According to the invention set forth in claim 16, in the sound reproduction device that outputs a reproduced signal by reproducing a recorded signal from a recording medium that is binaurally recorded and has a component that cancels the Talostok component added, the impulse signal generating means is configured to generate an impulse signal. Generate a signal. The electroacoustic conversion means converts the impulse signal into an impulse sound and radiates the impulse sound into an acoustic space. The acousto-electric conversion means collects the radiated impulse sound in the acoustic space, converts it into an electric signal S and outputs it, and can be worn on both ears of the listener. The characteristic flattening means 101 erases the acoustic characteristic component of the recording environment at the time of pie-no-chill recording, which is included in the reproduced signal S 1 of the recorded signal. The characteristic conversion means 102 converts the converted electric signal S
The acoustic characteristic data of the unique listening environment of the listener is calculated based on the characteristics of the flattened reproduced signal S +
01 is converted to match the acoustic characteristics of the listener's unique listening environment based on the acoustic characteristic data, and a component that cancels the crosstalk component to both ears of the listener is added and output.

According to the seventeenth aspect of the present invention, in the sound reproduction device that reproduces a recorded signal from a recording medium on which binaural recording has been performed and outputs a reproduced signal, the impulse signal generating means generates an impulse signal.

The electroacoustic conversion means converts the impulse signal into an impulse sound and radiates the impulse sound into an acoustic space. The acousto-electric conversion means collects the radiated impulse sound in the acoustic space, converts it into an electric signal S and outputs it, and can be worn on both ears of the listener. The characteristic conversion means 102 calculates the acoustic characteristic data of the unique listening environment that the listener has based on the converted electric signal 5163, adds a component that cancels the crosstalk component to both ears of the listener, and outputs the result. .

According to the invention as set forth in claim 18, in the sound reproduction device that outputs a reproduced signal by reproducing a recorded signal from a recording medium that is binaurally recorded and has a component that cancels a crosstalk component added thereto, the impulse signal generating means comprises: Generate an impulse signal. The electroacoustic conversion means converts the impulse signal into an impulse sound and radiates the impulse sound into an acoustic space. The acousto-electric conversion means collects the radiated impulse sound in the acoustic space, converts it into an electric signal S and outputs it, and can be worn on both ears of the listener. The characteristic converting means 102 calculates acoustic characteristic data of the listener's unique listening environment based on the converted electrical signal S, adds a component that cancels the crosstalk component to both ears of the listener, and outputs the result. .

〔Example〕

Next, preferred embodiments of the present invention will be described based on the drawings.

In this embodiment, when reproducing a recorded signal recorded by a dummy head, etc., the characteristics of the known transfer function of the dummy head, etc. included in the reproduced signal are flattened, and an impulse sound is emitted from the speaker to listen to the listener (listener). ), extracting the transfer function based on the listener's unique head and pinna shape, etc., and converting the characteristics of the flattened reproduced signal into the listener's unique auditory-acoustic characteristics. It has been disclosed.

FIG. 2 shows the configuration of a binaural surround reproduction device. This binaural surround playback device 7
includes a binaural microphone 1, a reproduction characteristic control device 2, a reproduction device 3, an amplification device 5, and a speaker 6.

The output side of the binaural microphone 1 is connected to the input side of the reproduction characteristic control device W2. The output side of the reproduction device 3 is connected to the input side of the reproduction characteristic control device 2. The output side of the reproduction characteristic control device 2 is connected to the input side of the amplifier device 5. The output side of the amplifier device 5 is connected to a speaker 6.

The binaural microphone 1 has a left channel microphone IL and a right channel microphone IR. The reproduction characteristic control device 2 has a selector 11 and a
It has a /D converter 12, a digital signal processing device 13, a D/'A converter 14, an impulse signal generator 15, a selector 16, and an external input device 17. The input side of the selector 11 is connected to the output side of the binaural microphone 1 and the output side of the playback device 3. The output side of the selector 11 is connected to the input side of the A/'D converter 12. A/D converter 12
The output side of is connected to the input side of the digital signal processing device 13. The output side of the digital signal processing device 13 is D
/' Connected to the input side of the A converter 14.

The output side of the D/'A converter 14 and the output side of the impulse signal generator 15 are connected to the input side of the selector 16. The output side of the selector 16 is connected to the input side of the amplifier device 5. External input device 17 is connected to digital signal processing device 13 . The speaker 6 includes a left channel speaker 6L and a right channel speaker 6R.

Here, the digital signal processing device 13 is defined in claim 1.2.
．． The signal processing device according to item 3 or 4 is configured. Further, the binaural surround playback device 7 is claimed in claim 5.6.7.
Alternatively, the sound reproduction device according to 8 is configured. Here, the impulse signal generator 15 constitutes an impulse signal generation means, the speaker 7 constitutes an electroacoustic conversion means, and the binaural microphone 1 constitutes an acoustoelectric conversion means.

Next, FIG. 3 shows a detailed configuration of the binaural microphone 1. The binaural microphone 1 has a left channel microphone IL and a right channel microphone IR that can be attached to the ear canal of the listener LS (FIG. 3(A)). As shown in FIG. 3(B), each microphone has a main body B that can be inserted into an ear canal, a windshield cap W, a cord C, and a connection jack T. A connection shack T connects the binaural microphone 1 to a preamplifier 2.

FIG. 4 shows a detailed configuration of the digital signal processing device 13. This digital signal processing device 13 includes an input/output interface circuit 21, a bus 22, a sequence control section 23, an arithmetic unit 24, a RAM 25, and a ROM 2.
6.

Input/output interface circuit 21 and sequence control section 2
3, arithmetic unit 24, RAM 25, and ROM 26
are connected via a bus 22.

Further, the input/output interface circuit 21 and the sequence control section 23, and the sequence control section 23 and the arithmetic unit 24 are connected via signal lines.

In this digital signal processing device 13 , signals from the outside are taken in by an input/output interface circuit 21 . In addition to being stored in the RAM 25 as is, this signal is also stored in the RAM 25 after being subjected to calculation or processing by the sequence control section 23 or the calculation unit 24, and is outputted to the outside via the input/output interface circuit 21 as appropriate. . Calculation or processing is performed using built-in programs inside the sequence control section 23 and the calculation unit 24, as well as from the ROM 2.
It is also executed by a program stored in 6.

Next, FIG. 5 shows an example of the configuration of the arithmetic unit 24. This arithmetic unit 24 includes a register 31.32, a multiplier 33, a selector 34.35, an addition/logic circuit 36, and an accumulation register 37. By adopting the configuration as shown in FIG. 5, it is possible to perform addition, subtraction, cumulative multiplication, etc. When the arithmetic unit 24 flattens or adds transfer function characteristics, the arithmetic unit 24 is caused to perform an arithmetic operation as a so-called digital filter.

As shown in Figure 6, a digital filter is a circuit that shifts input data using a delay device T, multiplies each shifted data by a coefficient, and adds them together using an adder Σ. Cyclic F I R (Fi
nite 1mpu eRzpon+eFilter)
filter (6th BU (A)) and cyclic filter 11R (Infinite Impul+eRe+p
on+eFilt++) filter (FIG. 6(B)), any filter may be used in application of the present invention.

An overview of the operation of a digital filter will be explained below, taking FIR as an example. The 2-conversion of the FIR impulse response is called the transfer function H(1), and is expressed as: Here, equation (1) represents a transfer function, and expresses a or b in equations (2) and (3) or the coefficients of each coefficient unit in FIG. 6(A). These coefficients are calculated and stored in RAM2 in Figure 4.
5 or the like, it is possible to obtain arbitrary transfer function characteristics. Also, by performing the inverse operation,
It is possible to obtain transfer function characteristics that are inversely related to a certain transfer function.

Next, the operation of this binaural surround reproduction system 7 will be explained. After the listener LS attaches the binaural microphone 1 to both ears, the listener LS receives an impulse signal 515 from the impulse signal generator 15 in the reproduction characteristic control device 2.
Generate L' 515R. The subscript R in the signal S indicates that it is the stereo left 5L (L) channel, and the subscript R in the signal S indicates that it is the stereo right (R) channel. The selector 16 can select and switch between the input from the D/A converter 14 and the input from the impulse signal generator 15, and in this case, is set to select the input from the impulse signal generator 15. Impulse signal S
, 515L 15R are input to the amplifier 5, amplified to an appropriate level, and then outputted as a signal S S to the speaker 65L 5R . Speaker 6 sends signal S SS to I5L
Convert to 5R pulse sound S XS and output. Inn 6L
6R Pulse sound S SS is binaural microphone 6L
The impulse response signal S
The signal is converted into S and output to the reproduction characteristic control device 21L.IR. Impulse response signal S 1S is IL
It is output to the IR selector 11. The selector 11 can select and switch between the input from the binaural microphone 1 and the input from the playback device 3, but in this case, it is set to select the input from the binaural microphone 1. Signal S
S is selector IL'! A/D comparator 11L as signal S 18 from R 11
IIR - Input on evening 12. The A/D converter 12 converts the analog signal 5IIL"IIR into a digital signal S18 and outputs the digital signal 12L.
12R is output to the processing device 13. Digital signal processing device 1
3 extracts the transfer function characteristic specific to the listener LS from the digital signal 512L''+2R and stores it internally.

An example of the relationship between this impulse sound and its response is shown in FIG. FIG. 7(A) is a diagram schematically showing the characteristics of impulse sound, and the vertical axis represents the gain of the sound. The solid line portion in FIG. 7(B) is a diagram schematically showing an example of the characteristics of the response (transfer function) due to this impulse sound, and similarly, the vertical axis represents the gain of the response. This transfer function characteristic is stored inside the digital signal processing device 13. From this, it can be seen that the transfer function can be flattened by providing characteristics as shown by the broken line in FIG. 7(B).

Next, after the listener LS wears the binaural microphone IL in his left ear, the impulse signal generator 15 in the reproduction characteristic control device 2 generates a right (R) channel impulse signal S 1 .

5R Then, the same operation as above is performed to extract the listener-specific left ear transfer function characteristic for the right (R) channel impulse and store it in the digital signal processing device 13.

Next, after the listener LS wears the binaural microphone IR in his right ear, the impulse signal generator 15 in the reproduction characteristic control device 2 generates an impulse signal S of the left (L) channel.

5L Then, the same operation as above is performed to extract the listener-specific left ear transfer function characteristic for the left (L) channel impulse and store it in the digital signal processing device 13.

Therefore, through these operations, the transfer function regarding crosstalk of the listener LS is extracted and stored.

FIG. 8 is a diagram illustrating crosstalk.

That is, originally, the sound from the left channel speaker 6L is heard with the left ear, and the sound from the right channel speaker 6R is heard with the right ear, so that a desired stereo sound field effect or surround effect can be obtained. However, in reality, some of the sound from the left channel speaker 6L is also heard by the right ear, and some of the sound from the right channel speaker 6R is also heard by the left ear. As a result, the three-dimensional effect and realism of the sound are impaired. This is called a crosstalk phenomenon. In order to cancel this crosstalk, as mentioned above, if we set a transfer function that has an inverse relationship to the transfer function related to crosstalk in the left ear (for example, the broken line in FIG. 7(B)), crosstalk can be canceled.

The same applies to the left ear.

Here, a recording medium 4 such as a compact disc or a compact cassette tape is loaded into the playback device 3, which is binaurally recorded using a dummy head or the like, and on which acoustic components for canceling left and right crosstalk acoustic parts are also recorded at the same time. and reproduce the binaural reproduction signal S18.
output.

3L 3R In this case, the selector 11 is switched to the input side from the playback device 3. The binaural reproduction signal S3L'S3R passes through the selector 11 and is input to the A/D converter 12 as the signal 5IIL'IIR.
is converted into a digital signal 512L1S12R by
The signal is input to the digital signal processing device 13. Transfer function characteristics of a dummy head or the like on which binaural recording has been performed are input to the digital signal processing device 13 in advance from an external input device 17 . Alternatively, the transfer function characteristics of the recording environment during binaural recording are recorded inside the recording medium 4 (for example, in the first part of the recording area), and
It is automatically set when playback of the recording medium 4 is started.

The digital signal processing device 13 calculates a transfer function that is an inverse function to the transfer function of this binaural reproduction signal, and then performs a calculation to convert it into a transfer function specific to the listener LS obtained by the impulse response. . Therefore,
The digital playback signal 512L' 512R from the playback device 3 input to the digital signal processing device 13 is first processed based on the acoustic characteristics (transfer function characteristics of the recording environment during binaural recording) based on the shape of the head and pinna of the dummy head, etc. ) is removed and the characteristics are flattened, the listener L
It is adjusted to the auditory acoustic characteristics (transfer function characteristics of the listener's unique listening environment) based on the shape of S's head and pinnae, etc. In this case, the digital signal processing device 13, based on the internally stored transfer function related to the listener-specific Talostalk,
At the same time, an acoustic component is added to cancel out the crosstalk between the listener's ears. The output from the digital signal processing device 13 is input to the D/A converter 14 as signals 513L' and 513R. The D/A converter 14 converts the signal 513LSS13R, which is a digital signal, into an analog signal 514L"+4H and outputs it to the selector 16. In this case, the selector 16
Switch so that input from 4 is selected. The analog signal 5140.514R passes through the selector 16 and becomes the signal 51.
It is input to the amplifier device 5 as 6L '"" +6R,
After being amplified to an appropriate level, it is input to the speaker 6 as a signal S SS 5L 5R , converted into sound, and radiated toward the listener LS.

Thereby, the listener LS can listen to reproduced sound with a rich three-dimensional effect and a sense of realism.

Also, if a component that cancels crosstalk is added to the recording when recording on a recording medium, the crosstalk component should be canceled, or the actual listener and the person who extracted the crosstalk transfer function are the same. Because it is not a person,
Due to the subtle differences, conventional devices may not be able to adequately cancel crosstalk. Alternatively, even if the relative relationship between the speaker and the listening position of the listener is different from that at the time of recording due to the conditions of the listening room, the conventional apparatus may not be able to provide a sufficient losstalk cancellation effect. However, according to this embodiment, these problems are solved and a sufficient losstalk cancellation effect can be obtained. The recording on the recording medium may be a binaural recording without any crosstalk cancellation component added. This is because this embodiment can deal with this problem during playback.

Further, in this embodiment, the characteristic conversion means may not have a crosstalk canceling function, or may have only a crosstalk canceling function.

Note that the playback signal of the recorded signal recorded binaurally, which is the object of the present invention, can be obtained by playing back the recorded signal using a dummy head, or by using a binaural microphone shown in Figure 3 attached to the ear of a person other than the listener. It may also be a reproduction of a recorded signal. In this case, use the impulse response to calculate the transfer function of the listener's head, etc., calculate the inverse function to flatten the acoustic characteristics, and then use the impulse response to calculate the transfer function of the listener's head, etc. It is sufficient to find a transfer function and convert it into auditory-acoustic characteristics specific to the listener. Therefore, the present invention is applicable not only to the playback of commercially recorded music sources, but also to personal live recordings.

Binaural recording can also be performed by signal processing. That is, once the transfer function characteristics of a dummy head or an actual human head are extracted, signal processing can be performed thereafter using only the obtained transfer function. or,
Individual coefficient values may be modified to create a model-like head transfer function for processing.

〔Effect of the invention〕

As explained above, according to the present invention, the characteristics of the reproduced sound can be adjusted according to the acoustic characteristics based on the listener's unique head shape, pinna shape, etc., and the three-dimensional feeling and sense of presence of the reproduced sound can be further enhanced. It also has the advantage of being able to improve the crosstalk and obtain a crosstalk cancellation effect.

[Brief explanation of drawings]

FIG. 1 is a diagram illustrating the principle of the present invention according to claim 1, FIG. 2 is a diagram showing the configuration of a preferred embodiment of the present invention, FIG. 3 is a diagram showing the detailed configuration of a binaural microphone, and FIG. is a diagram showing the detailed configuration of the digital signal processing device in FIG. 2, FIG. 5 is a diagram showing an example of the configuration of the arithmetic unit in FIG. 4, FIG. 6 is a diagram showing the configuration of the digital filter, and FIG. 8 is a diagram illustrating an example of the relationship between an impulse sound and its response, FIG. 8 is a diagram illustrating crosstalk, and FIG. 9 is a diagram illustrating the configuration of a conventional binaural surround recording/playback system. 1...Binaural microphone 2...Reproduction characteristic control device 3...Reproduction device 4...Recording medium 5...Amplification device 6...Speaker 7...Binaural surround reproduction device 11...
Selector 12...A/D converter 13...Digital signal processing device 14...D/A converter 15...Impulse signal generator 16...Selector 17...External input device 21...Input/output Interface circuit 22... Bus 23... Sequence control unit 24... Arithmetic unit 25... RAM 26... ROM 31... Register 32... Register 33... Multiplier 34... Selector 35 ...Selector 36...Addition/logic circuit 37...Accumulation register 101...Characteristic flattening means 102...Characteristic converting means 103...Signal processing device A...Amplifier B...Microphone Main unit C...Microphone cord DH...Dummy head EN...Encoder LS...Listener M...Recording medium MC...Microphone PL...Playback device RE...Recording device SP...Speaker SS...Sound source T...Connection jack W...Windshield cab

Claims (1)

[Scope of Claims] 1. A signal processing device for processing a recorded signal recorded binaurally, comprising: characteristic flattening means for eliminating acoustic characteristic components of the recording environment at the time of the binaural recording, which are included in the playback signal of the recorded signal; A signal processing device comprising: a characteristic converter that converts the characteristics of the flattened reproduction signal into auditory acoustic characteristics of a listening environment specific to a listener. 2. Claim 1, wherein the acoustic characteristics of the recording environment are transfer functions of the recording environment, and the auditory acoustic characteristics of the listening environment specific to the listener are transfer functions of the listening environment specific to the listener. The signal processing device described. 3. The signal processing device according to claim 1 or 2, wherein the recording environment includes a dummy head. 4. The signal processing device according to claim 1 or 2, wherein the recording environment includes a human head. 5. The signal processing device according to claim 1 or 2, wherein the recording environment is formed by signal processing. 6. A sound reproduction device that reproduces a recorded signal from a recording medium on which binaural recording is performed and outputs a reproduced signal, comprising an impulse signal generating means for generating an impulse signal, and converting the impulse signal into an impulse sound and emitting it into an acoustic space. an electroacoustic transducer that collects the radiated impulse sound in the acoustic space, converts it into an electrical signal, and outputs it; an acoustoelectric transducer that can be worn on both ears of a listener; a characteristic flattening means for eliminating acoustic characteristic components of the recording environment at the time of the binaural recording included in the playback signal; and calculating acoustic characteristic data of the unique listening environment of the listener based on the converted electrical signal; a characteristic converting means for converting and outputting the characteristics of the flattened reproduction signal based on the acoustic characteristic data so as to match the acoustic characteristics of the listening environment unique to the listener; . 7. Claim 6, wherein the acoustic characteristics of the recording environment are transfer functions of the recording environment, and the auditory acoustic characteristics of the listening environment specific to the listener are transfer functions of the listening environment specific to the listener. The described sound reproduction device. 8. The sound reproduction device according to claim 6 or 7, wherein the recording environment includes a dummy head. 9. The sound reproduction device according to claim 6 or 7, wherein the recording environment includes a human head. 10. The sound reproduction device according to claim 6 or 7, wherein the recording environment is formed by signal processing. 11. A signal processing device for processing a binaurally recorded recording signal, comprising: a characteristic flattening means for erasing an acoustic characteristic component of the recording environment at the time of the binaural recording, which is included in a reproduction signal of the recorded signal; Characteristic converting means converts the characteristics of the reproduced signal into auditory-acoustic characteristics of a listener's unique listening environment, and adds and outputs a component that cancels a crosstalk component to both ears of the listener. signal processing device. 12. A sound reproduction device that reproduces a recorded signal from a recording medium on which binaural recording is performed and outputs a reproduced signal, comprising an impulse signal generating means for generating an impulse signal, and converting the impulse signal into an impulse sound and emitting it into an acoustic space. an electroacoustic transducer that collects the radiated impulse sound in the acoustic space, converts it into an electrical signal, and outputs it; an acoustoelectric transducer that can be worn on both ears of a listener; a characteristic flattening means for eliminating acoustic characteristic components of the recording environment at the time of the binaural recording included in the playback signal; and calculating acoustic characteristic data of the unique listening environment of the listener based on the converted electrical signal; Converting the characteristics of the flattened reproduced signal to match the acoustic characteristics of the listening environment specific to the listener based on the acoustic characteristic data, and adding a component that cancels crosstalk components to both ears of the listener. 1. A sound reproducing device comprising: a characteristic converting means for outputting. 13. In a signal processing device that processes a recording signal that is binaurally recorded and has a component that cancels a crosstalk component added, the acoustic characteristic component of the recording environment at the time of the binaural recording that is included in the playback signal of the recording signal is eliminated. A signal processing device comprising: a characteristic flattening unit; and a characteristic converting unit that converts the flattened characteristics of the reproduced signal into auditory-acoustic characteristics of a listening environment unique to a listener. 14. In a sound reproduction device that reproduces a recorded signal from a recording medium that is binaurally recorded and has a component that cancels a crosstalk component added thereto and outputs a reproduced signal, an impulse signal generating means that generates an impulse signal, and the impulse signal an electroacoustic conversion means that converts the radiated impulse sound into an impulse sound and radiates it into an acoustic space; and an electroacoustic conversion means that collects the radiated impulse sound in the acoustic space, converts it into an electric signal, and outputs it, which can be worn on both ears of a listener. acousto-electric conversion means; a characteristic flattening means for erasing acoustic characteristic components of the recording environment at the time of the binaural recording included in the reproduction signal of the recorded signal; a characteristic converting means for calculating acoustic characteristic data of a listening environment of the listener, converting the characteristics of the flattened reproduced signal to match the acoustic characteristics of the listening environment specific to the listener based on the acoustic characteristic data, and outputting the characteristic; A sound reproduction device characterized by having the following. 15. In a signal processing device that processes a recording signal that is binaurally recorded and has a component that cancels a crosstalk component added, the acoustic characteristic component of the recording environment at the time of the binaural recording that is included in the playback signal of the recording signal is eliminated. a characteristic flattening means, converting the characteristics of the flattened reproduced signal into auditory-acoustic characteristics of a listener's unique listening environment, and adding a component that cancels a crosstalk component to both ears of the listener, and outputting the same. A signal processing device comprising: characteristic conversion means. 16. In a sound reproduction device that reproduces a recorded signal from a recording medium that is binaurally recorded and has a component that cancels the component added thereto and outputs a reproduced signal, an impulse signal generating means that generates an impulse signal; and an impulse signal that generates an impulse signal. An electroacoustic conversion means that converts the sound into sound and radiates it into an acoustic space, and an acoustic device that can be worn in both ears of a listener, which collects the radiated impulse sound in the acoustic space, converts it into an electric signal, and outputs it. electrical conversion means; characteristic flattening means for eliminating acoustic characteristic components of the recording environment at the time of the binaural recording included in the reproduction signal of the recorded signal; calculating acoustic characteristic data of the environment, converting the characteristics of the flattened reproduced signal based on the acoustic characteristic data so as to match the acoustic characteristics of the listening environment specific to the listener, and transmitting the signal to both ears of the listener. 1. A sound reproduction device comprising: characteristic conversion means for adding and outputting a component that cancels a crosstalk component. 17. A sound reproduction device that reproduces a recorded signal from a recording medium on which binaural recording is performed and outputs a reproduced signal, comprising an impulse signal generating means for generating an impulse signal, and converting the impulse signal into an impulse sound and emitting it into an acoustic space. an electroacoustic transducer that collects the radiated impulse sound in the acoustic space, converts it into an electrical signal, and outputs it, which can be worn on both ears of a listener; Characteristic converting means that calculates acoustic characteristic data of a unique listening environment possessed by the listener based on an electrical signal, and adds and outputs a component that cancels a crosstalk component to both ears of the listener. A sound reproduction device featuring: 18. In a sound reproduction device that reproduces a recorded signal from a recording medium that is binaurally recorded and has a component that cancels a crosstalk component added thereto and outputs a reproduced signal, an impulse signal generating means that generates an impulse signal, and the impulse signal an electroacoustic conversion means that converts the radiated impulse sound into an impulse sound and radiates it into an acoustic space; and an electroacoustic conversion means that collects the radiated impulse sound in the acoustic space, converts it into an electric signal, and outputs it, which can be worn in both ears of a listener. an acousto-electric conversion means, which calculates acoustic characteristic data of a unique listening environment of the listener based on the converted electric signal, and adds a component that cancels a crosstalk component to both ears of the listener. A sound reproducing device comprising: a characteristic converting means for outputting an output signal.