JPH07336798A - Reproduction device for sound filed signal - Google Patents

Abstract

PURPOSE:To provide a sound reproducing device which enhances a real sanse of sound image control using an FIR filter. CONSTITUTION:A difference signal extracting device 3 obtains a difference between two received signals and its output signal is given to arithmetic circuits 4, 5, 6, 7 and a sound image is localized to the left, right sides or left, right rear sides of a listener 16 by FIR filtering processing. Outputs of the arithmetic circuits 4, 5, 6, 7 are given to adders 12, 13 via delay devices 8, 9, 10, 11. The outputs are delayed by a delay times T1, T2 respectively. The adder 12 adds output signals from an input terminal 2, the delay devices 8, 10 in an optional ratio and the adder 13 adds output signals from an input terminal 1, the delay devices 9, 11 in an optional ratio and the output is outputted to the speakers 14, 15. Thus, a spread sound reproduction without a sense of inverted phase is attained with a simple system configuration.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound field signal reproducing apparatus for reproducing realistic sound in AV (audio / visual) equipment.

[0002]

2. Description of the Related Art In recent years, VTRs have been used in the video and audio fields.
Due to the spread of, it is desired to have a large screen and realistic sound reproduction in order to enjoy movies at home, and not only movies but also realistic sound reproduction to enjoy music software,
It is necessary to develop hardware to support this.

A conventional sound field signal reproducing device will be described below with reference to the drawings. FIG. 15 is a hardware block diagram showing a configuration of a conventional sound field signal reproducing device.
In FIG. 15, reference numerals 1 and 2 denote input terminals for inputting signals, 62
Is a multiplier that multiplies the input signal by -1, 63 is an adder that adds the input signal, 64 is a delay device that delays the input signal by time, 12-
5, 13-5 is an adder for adding the input signals, 65 is a multiplier for multiplying the input signals by -1, 14, 15 is a speaker for acoustically reproducing the signal to the outside, 16 is a listener facing the speakers 14, 15. And M
L (t) (t represents continuous time, ML (t) represents a time function, and so on) is the Lch signal of the stereo audio signal, and MR (t) is the stereo audio signal. Rch signal, τ3 is the delay time in the delay unit 64.

The operation of the conventional sound field signal reproducing device configured as described above will be described with reference to FIG.

ML (t) is input from the input terminal 1, MR (t) is input from the input terminal 2, the input signal is divided into two, and MR (t) is added by the adder 63. And adder 12
5, and ML (t) is input to the multiplier 62 and the adder 13-5. The multiplier 62 multiplies ML (t) by -1, and the resulting -ML (t) is input to the adder 63. MR in adder 63
(t) and −ML (t) are added, and the result is MR (t) -ML (t)
Is output and input to the delay unit 64. In delay device 64, MR (t)-
ML (t) is delayed by time τ3 and MR (t-τ3) -ML (t-τ3) is output. The output signal of the delay unit 64 is branched into two, one signal is input to the adder 12-5 and the other signal is input to the multiplier 65. In the multiplier 65, MR (t-τ3) -ML (t-τ3) is multiplied by -1, and the result-(MR (t-τ3) -ML (t-τ3)) is added by the adder 1
Input to 3-5. In adder 12-5, MR (t) and MR (t-τ3) -ML
(t-τ3) is added, and the result MR (t) + MR (t-τ3) -ML (t-τ3) is output from the speaker 14. Adder 13
At −5, ML (t) and − (MR (t−τ3) -ML (t−τ3)) are added,
The result, ML (t) − (MR (t−τ3) −ML (t−τ3)), is output from the speaker 15.

At this time, from one of the two speakers, MR
(t-τ3) -ML (t-τ3), from the other is − (MR (t-τ3) -ML (t-τ3
The signals of 3)), which are in opposite phase to each other, are mixed with the input signal and reproduced, and this produces a sound field in which the localization of the sound image is unknown. (Or, the minus signal cancels out the crosstalk component, giving the impression that the left and right signals are from the outside of each speaker.) Then, ML (t) is a direct sound that has not been processed. ) And MR (t) are adjusted to create a sound field with a sense of spaciousness and realism.

[0007]

However, in the above-described configuration, adjustment is performed by the mix balance of the anti-phase sound and the direct sound, and the effect is small when the anti-phase sound is small, and the effect can be seen. On the other hand, when the anti-phase sound is increased, the anti-phase feeling becomes strong and the discomfort is brought. Further, when the input signal is a voice signal, the voice component is reduced when the difference signal of the input signals is added to the input signal, which causes a problem that the reproduced voice becomes unclear.

In consideration of the above-mentioned conventional problems, an object of the present invention is to provide a sound field signal reproducing apparatus capable of clearly reproducing an audio signal and reproducing a natural spread having a realistic sensation with a simple system configuration. Is to provide.

[0009]

In order to achieve the above object, the invention according to claim 1 of the present application provides an input means for inputting a 2ch signal and a difference or a sum of two signals input to the input means. The signal extraction means to be obtained, a calculation means for performing a convolution calculation for localizing a sound image in an arbitrary direction, a delay means for delaying an output signal of the calculation means by an arbitrary time, and an output signal of the delay means and an input signal to the input means. It is characterized in that it is provided with an adding means for adding the generated signals at an arbitrary ratio and an output means for outputting the output signal of the adding means to the outside.

According to a second aspect of the present invention, input means for inputting a 2ch signal, signal determining means for determining whether the 2ch signal input to the input means is a voice signal or a non-voice signal, and input to the input means. The correlation degree calculation means for obtaining the correlation between the input signals, the signal extraction means for obtaining the difference or the sum of the two input signals, the delay means for delaying the output signal of the signal extraction means by an arbitrary time, and the delay means. An addition means for weighting and adding the output signal and the signal input to the input means from the results obtained by the signal determination means and the correlation degree calculation means; and an output means for outputting the output signal of the addition means to the outside. It is characterized by including.

According to a third aspect of the present invention, input means for inputting a 2ch signal, signal determining means for determining whether the 2ch signal input to the input means is a voice signal or a non-voice signal, and input to the input means. The correlation degree calculating means for obtaining the correlation between the input signals, the signal extracting means for obtaining the difference or the sum of the two input signals, the calculating means for performing the convolution operation for localizing the sound image in an arbitrary direction, and the calculating means. A delay means for delaying the output signal by an arbitrary time, and an addition for weighting and adding the output signal of the delay means and the signal input to the input means from the results obtained by the signal discriminating means and the correlation degree calculating means. It is characterized by comprising means and output means for outputting the output signal of the adding means to the outside.

According to a fourth aspect of the present invention, the input means for inputting the 2ch signal, the signal extracting means for obtaining the difference or the sum of the two signals input to the input means, and the output signal of the signal extracting means Signal processing means for adding reflected sound or reverberation, operation means for performing convolution operation for localizing a sound image in an arbitrary direction, delay means for delaying the output signal of the operation means for an arbitrary time, and output signal of the delay means And adding means for adding the signals input to the input means at an arbitrary ratio,
Output means for outputting the output signal of the addition means to the outside.

According to a fifth aspect of the present invention, an input means for inputting a 2ch signal, a signal determining means for determining whether the 2ch signal input to the input means is a voice signal or a non-voice signal, and input to the input means. Correlation degree calculating means for obtaining the correlation between the generated 2ch signals, signal extracting means for obtaining the difference or sum of the two signals input to the input means, and signal for adding reflected sound or reverberation to the output signal of the signal extracting means Processing means, operation means for performing convolution operation to localize a sound image in an arbitrary direction, delay means for delaying an output signal of the operation means by an arbitrary time, output signal of the delay means and a signal input to the input means Is provided with an addition means for weighting and adding from the results obtained by the signal discrimination means and the correlation degree calculation means, and an output means for outputting the output signal of the addition means to the outside.

The invention according to claim 6 of the present application, the input means for inputting the 2ch signal, the signal determining means for determining whether the 2ch signal input to the input means is a voice signal or a non-voice signal, and the input 2ch Correlation degree calculating means for obtaining the correlation of signals, difference signal extracting means for obtaining the difference between two signals input to the input means, signal processing means for adding reflected sound or reverberation to the output signal of the difference signal extracting means, An adding means for weighting and adding the output signal of the signal processing means and the signal input to the input means from the results obtained by the signal determining means and the correlation calculating means, and outputting the output signal of the adding means to the outside. And an output means for performing the same.

The invention according to claim 7 of the present application, the input means for inputting the 2ch signal, the signal determining means for determining whether the 2ch signal input to the input means is a voice signal or a non-voice signal, and the input 2ch Correlation degree calculating means for obtaining the correlation of the signals, difference signal extracting means for obtaining the difference between the two signals input to the input means, sum signal generating means for obtaining the sum of the two signals input to the input means, and difference First signal processing means for adding reflected sound or reverberation to the output signal of the signal extraction means, second signal processing means for adding reverberation to the output signal of the sum signal generation means, and first signal processing means And an output signal of the second signal processing means and a signal input to the input means are weighted from the results obtained by the signal discriminating means and the correlation degree calculating means, and the adding means is added. External output signal of adder Characterized by comprising an output means for outputting.

The invention according to claim 8 of the present application, the input means for inputting the 2ch signal, the signal determining means for determining whether the 2ch signal input to the input means is a voice signal or a non-voice signal, and the input 2ch Correlation degree calculating means for obtaining the correlation of the signals, difference signal extracting means for obtaining the difference between the two signals input to the input means, sum signal generating means for obtaining the sum of the two signals input to the input means, and difference First signal processing means for adding reflected sound or reverberation to the output signal of the signal extraction means, second signal processing means for adding reflected sound or reverberation to the output signal of the sum signal generation means, and the first signal A first adding means for adding an output signal of the processing means and an output signal of the second signal processing means, and two first and second output signals for dividing the output signal from the first adding means into two, respectively. Signal splitting means and first and second signal splitting means Of the second adding means and the second adding means for weighting and adding the output signal of the stage and the signal input to the input means from the results obtained by the signal determining means and the correlation degree calculating means. Output means for outputting the output signal to the outside, and one second addition means of the second addition means is one of the two signals of the output signals of the first and second signal division means. It is characterized in that the signals are multiplied by -1 and then added.

[0017]

According to the invention of claim 1 of the present application having such characteristics, the signal extracting means is input to the input means.
The difference or sum of the two signals is calculated. Then, when the output signal of the signal extraction means is input, the calculation means performs a convolution calculation to localize the sound image in an arbitrary direction. Next, the delay means delays the output signal of the arithmetic means by an arbitrary time, and the adding means adds the output signal of the delay means and the signal input to the input means at an arbitrary ratio. Then, the output means outputs the output signal of the addition means to the outside.

According to the invention of claim 2 of the present application,
The signal determination means determines from the 2ch signal input to the input means whether the signal is a voice signal or a non-voice signal, and similarly the correlation degree calculation means obtains the correlation of the 2ch signal input to the input means. The signal extraction means is the 2ch input to the input means.
Find the difference or sum of signals. Then, the delay means delays the output signal of the signal extraction means by an arbitrary time. Next, the adding means weights and adds the output signal of the delay means and the signal input to the input means from the results obtained by the signal discriminating means and the correlation calculating means. Then, the output means outputs the output signal of the addition means to the outside.

According to the invention of claim 3 of the present application,
The signal determination means determines whether the 2ch signal input to the input means is a voice signal or a non-voice signal, and similarly the correlation degree calculation means obtains the correlation of the signals input to the input means. The signal extraction means obtains the difference or sum of the input 2ch signals. When the output signal of the signal extraction means is input, the calculation means performs a convolution calculation to localize the sound image in an arbitrary direction. Next, the delay means delays the output signal of the calculating means by an arbitrary time, and the adding means calculates the output signal of the delay means and the signal input to the input means by the signal discriminating means and the correlation degree calculating means. Add weights from.
Then, the output means outputs the output signal of the addition means to the outside.

According to the invention of claim 4 of the present application,
The signal extraction means finds the difference or sum of the two signals input to the input means. Then, the signal processing means adds reflected sound or reverberation to the output signal of the signal extraction means. Next, when the output signal of the signal processing unit is input, the calculation unit performs a convolution calculation to localize the sound image in an arbitrary direction. Then, the delay means delays the output signal of the arithmetic means by an arbitrary time. The addition means adds the output signal of the delay means and the signal input to the input means at an arbitrary ratio, and the output means outputs the output signal of the addition means to the outside.

According to the invention of claim 5 of the present application,
The signal determination means determines whether the 2ch signal input to the input means is voice or non-voice, and similarly the correlation degree calculation means obtains the correlation of the signals input to the input means. The signal extraction means finds the difference or sum of the 2ch signals input to the input means. Then, the signal processing means adds reflected sound or reverberation to the output signal of the signal extraction means. Next, when the output signal of the signal processing unit is input, the calculation unit performs a convolution calculation to localize the sound image in an arbitrary direction. Then, the delay means delays the output signal of the arithmetic means by an arbitrary time. The adding means weights and adds the output signal of the delay means and the signal input to the input means from the results obtained by the signal discriminating means and the correlation degree calculating means, and the output means adds the output signal of the adding means. Output to the outside.

According to the invention of claim 6 of the present application,
The signal determination means determines whether the 2ch signal input to the input means is a voice signal or a non-voice signal, and similarly the correlation degree calculation means obtains the correlation of the input signals. The difference signal extraction means finds the difference between the two signals input to the input means. Then, the signal processing means adds reflected sound or reverberation to the output signal of the difference signal extraction means. Next, the adding means weights and adds the output signal of the signal processing means and the signal input to the input means from the results obtained by the signal determining means and the correlation calculating means, and the outputting means outputs the output of the adding means. Output the signal to the outside.

According to the invention of claim 7 of the present application,
The signal determination means determines whether the signal input to the input means is a voice signal or a non-voice signal, and similarly the correlation degree calculation means obtains the correlation of the input signals. The difference signal extraction means finds the difference between the 2ch signals input to the input means, and the sum signal generation means finds the sum of the 2ch signals input to the input means. And
The first reflected sound adding means adds reflected sound or reverberation to the output signal of the difference signal extraction means, and the second signal processing means adds reflected sound or reverberation to the output signal of the sum signal generation means. Next, the adding means calculates the output signal of the first signal processing means, the output signal of the second signal processing means, and the signal input to the input means by the signal determining means and the correlation degree calculating means. From the addition means, and the output means outputs the output signal of the addition means to the outside.

According to the invention of claim 8 of the present application,
The signal determination means determines whether the 2ch signal input to the input means is a voice signal or a non-voice signal, and similarly the correlation degree calculation means obtains the correlation of the input 2ch signals. The difference signal extraction means finds the difference between the 2ch signals input to the input means, and the sum signal generation means finds the sum of the 2ch signals input to the input means. The first reflected sound adding means adds reflected sound or reverberation to the output signal of the difference signal extraction means, and the second signal processing means adds reflected sound or reverberation to the output signal of the sum signal generation means. Next, the first adding means adds the output signal of the first signal processing means and the output signal of the second signal processing means.
The first and second signal dividing means divides the output signal from the first adding means into two, and the second adding means inputs the output signal of the first and second signal dividing means and the input signal. The signals input to the means are weighted from the results obtained by the signal discriminating means and the correlation calculating means and added. The output means outputs the output signal of the second adding means to the outside. Also, one of the second adding means, the second adding means, adds -1 to one of the output signals of the first and second signal dividing means.
Multiply and add.

With the above-described structure and operation, the audio signal can be clearly reproduced, and the natural spread with a realistic sensation can be reproduced with a simple system structure.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A sound field signal reproducing apparatus according to a first embodiment of the present invention will be described with reference to the drawings. Figure 1 is the first
3 is a block diagram showing a configuration of a sound field signal reproducing apparatus in the embodiment of FIG. The parts having the same functions as those of the conventional example are designated by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 1, L input to the input terminal 1
The ch signal ML (t) and the Rch signal MR (t) input to the input terminal 2 are each branched into two, one signal is given to the difference signal extractor 3 and the other signal is added by the adder. Input to 13 and 12. The difference signal extractor 3 is a circuit for obtaining the difference between two input signals, and its output is given to the arithmetic circuits 4, 5, 6, 7. The arithmetic circuits 4 and 5 are listeners by FIR filtering
An FIR filter having an impulse response such that the sound image is localized to the right or rear of 16 and the arithmetic circuits 6 and 7 are impulse responses such that the sound image is localized to the left side or the left rear of the listener 16 by convolution calculation. Is a FIR filter having.

That is, the arithmetic circuit 4 uses the impulse response hRR (t)
The arithmetic circuit 5 has an impulse response hRL (t), the arithmetic circuit 6 has an impulse response hLR (t), and the arithmetic circuit 7 has an impulse response hLL (t). The output of the arithmetic circuit 4 is added to the adder 12 via the delay device 8, and the output of the arithmetic circuit 5 is delayed device.
The output of the arithmetic circuit 6 is given to the adder 13 via the delay circuit 10 and the output of the arithmetic circuit 7 is given to the adder 13 via the delay circuit 11 via the delay circuit 11. The delay devices 8, 9, 10, and 11 are circuits that delay the input signal by delay times τ1 and τ2, respectively.

The adder 12 includes an input terminal 2, a delay device 8 and a delay device 10.
Add the output signals of
This is a circuit that adds the output signals of 1, 1, 9 and 11 at an arbitrary ratio. The addition outputs of the adders 12 and 13 are output to the speakers 14 and 15, respectively. Although not shown, the signals output to the speakers 14 and 15 are output to the speakers 14 and 15 via a power amplifier that amplifies the signals.

The operation of the sound field signal reproducing apparatus according to the first embodiment having the above configuration will be described.

First, an acoustic signal such as voice or music is input from the input terminals 1 and 2, branched into two, one signal is input to the adders 12 and 13, and the other signal is a difference signal extractor. Entered in 3. The difference signal extractor 3 finds the difference between the input signals and inputs them to the arithmetic circuits 4, 5, 6, 7. The difference signal obtained by the difference signal extractor 3 is, for example, when the input signal is a music signal accompanied by a singer, the voice signal of the singer localized in the center is canceled, and the Lch and Rch inserted at the time of recording or broadcasting.
Often, the reverberation component of is mainly. Therefore, this difference signal is sometimes called a surround signal. Arithmetic circuit 6,
In 7, convolution calculation is performed so that the input signal localizes the sound image to the left side or the left rear side.

A method of virtually localizing a sound image in an arbitrary direction will be described with reference to FIG. FIG. 2 is a principle diagram of virtually generating a sound image localization equivalent to the case where a signal is reproduced from a speaker 45 provided on the left side by using the left channel speaker 15 and the right channel speaker 14. In the figure, speakers 14 and 15 are arranged on the left and right front sides of a listener 16. Then, the input signal S (t) is input to the arithmetic circuits 6 and 7. The arithmetic circuits 6 and 7 are FIR filters that perform convolutional calculations on the input signals with impulse responses hLR (t) and hLL (t), respectively. H1 (t) shown in the figure is an impulse response at the position of the left ear of the speaker 15 and the listener 16 (accurately, the position of the eardrum, which is the position of the ear canal when performing measurement). Similarly, h2 (t) is the impulse response at the position of the speaker 15 and the right ear of the listener 16 and h3 (t) is the speaker 14
And the impulse response at the position of the listener 16 left ear, h4
(t) is the impulse response at the position of the speaker 14 and the right ear of the listener 16, h5 (t) is the impulse response at the position of the speaker 45 and the left ear of the listener 16, h6 (t) is the speaker 45 and the listener 16 Is an impulse response at the position of the right ear of.

In such a structure, when the signal S (t) is output from the speaker 45, the sound reaching the ear of the listener 16 is as follows.

That is, the sound pressure L (t) in the left ear is expressed by (Equation 1).

[0035]

[Equation 1]

The sound pressure R (t) in the right ear is expressed by (Equation 2).

[0037]

[Equation 2]

However, * represents a convolution operation. In reality, the transfer function of the speaker itself is multiplied, but this is ignored, and it may be considered that the transfer function of the speaker is included.

The sound pressure, the impulse response, and the signal S (t) in (Equation 1) and (Equation 2) are considered as digital signals whose time is discrete, and they are (Equation 3), (Equation 4), and (Equation 4), respectively. 5), (Equation 6), (Equation 7)

[0040]

[Equation 3]

[0041]

[Equation 4]

[0042]

[Equation 5]

[0043]

[Equation 6]

[0044]

[Equation 7]

In this case, (Equation 1) and (Equation 2) become the following (Equation 8) and (Equation 9).

[0046]

[Equation 8]

[0047]

[Equation 9]

Here, the natural number n should actually be expressed by nT, and T represents a sampling time, but in general, T is omitted and expressed as (Equation 8) and (Equation 9).

Similarly, the signal S (t) is radiated from the speakers 14 and 15, and the following (Equation 10) and (Equation 11) are established for the sound reaching the listener 16. That is, the sound pressure of the left ear is
The following is (Equation 10).

[0050]

[Equation 10]

The sound pressure of the right ear is as follows (Equation 11).

[0052]

[Equation 11]

If it is assumed that the sound can be heard from the same direction if the head related transfer functions are equal (this assumption is generally correct), the following (Equation 12) to (Equation 15) are established.

[0054]

[Equation 12]

[0055]

[Equation 13]

[0056]

[Equation 14]

[0057]

[Equation 15]

Therefore, impulse responses hLL (n) and hLR (n) may be determined so that (Equation 13) and (Equation 15) are established.

For example, impulse responses h1 (t) to h6 (t), hL
Rewriting L (t) to hLR (t) in the frequency domain expression gives the following (Expression 16) to (Expression 23).

[0060]

[Equation 16]

[0061]

[Equation 17]

[0062]

[Equation 18]

[0063]

[Formula 19]

[0064]

[Equation 20]

[0065]

[Equation 21]

[0066]

[Equation 22]

[0067]

[Equation 23]

However, FFT () represents a Fourier transformed (FFT) function. Next, rewriting (Equation 13) and (Equation 15) in terms of frequency domain, the following (Equation 24) (Equation 2)
As in 5), the convolution operation is changed to multiplication, and after that, it becomes a transfer function obtained by Fourier transforming each impulse response.

[0069]

[Equation 24]

[0070]

[Equation 25]

In (Equation 24) and (Equation 25), since values other than the values of the transfer functions HLL (n) and HLR (n) are obtained by measurement, the following (Equation 26) and (Equation 27) are obtained. Transfer function HL
L (n) and HLR (n) can be obtained.

[0072]

[Equation 26]

[0073]

[Equation 27]

HLL (n) and HLR (n) thus determined
Inverse Fourier transform (IFFT) of hLL (n) and hLR (n) is used to apply the signal S (n) to the arithmetic circuits 6 and 7, and the signal output from the speaker 15 is given as hLL (n). , The signal output from the speaker 14 is convoluted with hLR (n), and the signal is emitted so that the listener 16 can hear the sound from that direction without actually sounding the speaker 45 on the left side. You can feel it is ringing.

By the above method, the sound image can be virtually localized in any direction.

FIG. 3 shows the basic configuration of the FIR filter that performs the convolution operation. In the figure, 46 is an input terminal for inputting a signal, 47 is a delay element for delaying the signal by τ, 48
Is a multiplier for multiplying an input signal by a value called a tap coefficient represented by h (n), 49 is an adder for adding the input signals, and 50 is an output terminal for outputting the signal. Usually such FIR
The filter is a DSP (Digital Signal) that performs multiplication and addition at high speed.
processor) or a dedicated LSI is used.

In the multiplier 48, the impulse response h (n) (n: 0 to N-1, where N is the required impulse response length) is set as a tap coefficient as shown in FIG. Further, the delay element 47 is set with a delay time corresponding to a sampling frequency when converting an analog signal into a digital signal. Then, the convolutional operation as shown in (Equation 8) and (Equation 9) is executed by repeating multiplication and addition and delay with respect to the signal input to the input terminal 46, respectively. This is because the signal processing is performed in the case of a digital signal, so in practice, an A / D converter for converting an analog signal into a digital signal before this FIR filter and a D / A for converting a digital signal into an analog signal after this. Although a converter is required, it is omitted in the figure (same below).

As described above, hLL (t) and hLR (t) are obtained, and the arithmetic circuits 6 and 7 virtually create a speaker on the left side or the left rear side of the sound image.

Similarly, the arithmetic circuits 4 and 5 perform a convolution operation so that the input signal localizes the sound image to the right side or the right rear side.

The output signals of the arithmetic circuits 4, 5, 6 and 7 are input to the delay units 8, 9, 10 and 11, respectively, and delayed by τ1 and τ2 time. It has been experimentally found that the optimum delay time for these signals is about 10 msec with respect to the input signal, and the difference between τ1 and τ2 has been experimentally found to be about 10 msec. The difference between the virtual signals localized on the right side and the left side of τ1 and τ2 is provided for separating the signals localized on the left and right sides.

Next, the output signals of the delay units 8, 9, 10, and 11 are input to the adders 12 and 13, respectively, and are arbitrarily combined with the signals MR (t) and ML (t) input to the input terminals 1 and 2. And the sound is reproduced from the speakers 14 and 15.

Next, a sound field signal reproducing apparatus according to the second embodiment of the present invention will be described with reference to FIG. Figure 2 is the second
3 is a block diagram showing a configuration of a sound field signal reproducing apparatus in the embodiment of FIG. The parts having the same functions as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In FIG. 4, the signals ML (t) and MR (t) input to the input terminals 1 and 2 are converted into difference signals by the difference signal extractor 3 and input to the arithmetic circuits 6 and 7. The output signals of the arithmetic circuits 6 and 7 are respectively branched into two, input to the delay units 8, 9, 10 and 11, and emitted from the speakers 14 and 15 via the adders 12 and 13.

With respect to the operation of the sound field signal reproducing apparatus in the second embodiment thus constructed, only the parts different from those in the first embodiment will be described below.

The output signals of the arithmetic circuits 6 and 7 are respectively branched into two, and the output signals of the arithmetic circuit 6 are delayed by the delay units 9 and 10.
The output signal of the arithmetic circuit 7 is input to the delay devices 8 and 11. When the sound image is localized left and right for the listener, two impulse responses hLL (t) and hL for localizing the sound image to the left
By setting R (t) to the left and right, it is possible to easily localize the sound image to the right. This is based on the assumption that the impulse responses of the listener's left and right ears are symmetrical. Therefore, as shown in this figure, the arithmetic circuits 6 and 7
By connecting the output signals of (1) and (2) through the delay units 8, 9, 10, and 11 so that one signal is straight and the other signal is left-right inverted, the left and right sound images are reduced in the scale of the arithmetic circuit. It is possible to generate. The subsequent operation is similar to that of the first embodiment.

Next, a sound field signal reproducing apparatus according to the third embodiment of the present invention will be described with reference to FIG. Figure 3 is the third
3 is a block diagram showing a configuration of a sound field signal reproducing apparatus in the embodiment of FIG. The parts having the same functions as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In FIG. 5, the signals ML (t) and MR (t) input to the input terminals 1 and 2 are converted into the difference signal S (t) by the difference signal extractor 3, and the delay units 19-1 and 19 are provided. -Entered in 2. Delay device 19-1,
19-2 delays the input signal S (t) by τ1 and τ2 time.

In addition, the signal ML input to the input terminals 1 and 2
(t) and MR (t) are input to the signal determination circuit 20 and the correlator 21. The signal determination circuit 20 detects a silent section of the input signal and determines whether the signal is a voice signal or a non-voice signal. The correlator 21 is a circuit that finds the amount of correlation between input signals. S (t-τ1) is the output signal from the delay device 19-2, and similarly S (t-τ2) is the output signal from the delay device 19-1 and is input to the adders 23 and 22. The output signals of the delay devices 19-1 and 19-2 and the signals input to the input terminals 1 and 2 are added to the adders 22 and 2, respectively.
Entered in 3. The adders 22 and 23 add the input signals by changing the addition amount from the results obtained by the signal determination circuit 20 and the correlation path 21, and radiate from the speakers 14 and 15.

Regarding the operation of the sound field signal reproducing apparatus according to the third embodiment having the above-mentioned configuration, only the part different from that of the first embodiment will be described below.

The signal discrimination circuit 20 inputs MR (t)
And ML (t) are added to each other to detect the frequency of occurrence of the silent section (interruption of the signal) of the sum signal, and the signal determination means determines whether the input signal is a voice signal or a non-voice signal based on the frequency of occurrence. .

FIG. 6 shows the waveform of the audio signal. In FIG. 6, the horizontal axis represents time and the vertical axis represents amplitude, and shows the case where "Thank you very much" is spoken as indicated by the Roman letters above the waveform. As this figure shows,
In the case of a voice signal, some silent sections are always generated at a certain time interval (in this example, a silent section is generated twice per second). In the signal determination circuit 20 of the present embodiment, by utilizing this property, it is assumed that the sound is generated when a certain number of silent sections are generated within a certain time, and when it is not, the signal is regarded as a non-voice signal, Or non-voice.
The determination degree A is A = (A + ΔA) for a non-voice signal and A = (A−ΔA) for a voice signal, where ΔA is the amount of change when it is determined to be voice. And According to this equation, A is small when the input signal is determined to be a voice signal, and A is large when the input signal is determined to be a non-voice signal. Thus, instead of determining whether the input signal is voice or non-voice by 0 or 1 each time, a certain amount of ΔA is determined, and the determination degree is updated for each determination as in the above equation. By adopting the method, it becomes possible to deal with the case where an erroneous determination occurs. Then, the determination degree A thus obtained is output to the adders 22 and 23.

The correlator 21 is a degree-of-correlation calculating means for calculating the correlation amount between the input signals, and calculates the correlation between the input signals by the following equation.

[0093]

[Equation 28]

According to the above equation, when the input 2ch signal is a monaural signal or a signal close to it, the numerator becomes zero or small, and α also becomes close to zero. Also, the input 2ch signal is a stereo signal (the correlation between ML (t) and MR (t) is low).
In this case, the molecule becomes large and α also becomes large.

The addition rate of each signal in the adders 22 and 23 is controlled by the determination result of the signal determination circuit 20 and the value obtained by the correlator 21. The adders 22 and 23 perform addition as in the following equation.

[0096]

[Equation 29]

[0097]

[Equation 30]

Here, MR '(t) and ML' (t) are output signals from the adders 22 and 23. In the above equation, ML (t), MR that should be localized forward
By adjusting the ratio of (t) and the surround signal, the addition calculation is performed so that a natural presence can be obtained. That is, according to this equation, when the correlation of the input signals is small (the stereo feeling is large), the signal extracted by the difference signal extractor 3 is reproduced large, and when the correlation of the input signals is large (the stereo feeling is small). The signal extracted by the difference signal extractor 3 is reproduced small. However, since it is determined at the same time whether the input signal is voice or non-voice, the clarity of voice can be ensured.

Also, in (Equation 29) and (Equation 30), α
The value of (Equation 28) is used as it is, but it is actually used after being converted into a value corresponding to about 0 to 1. Further, this value may be changed depending on the magnitude of the effect of enlarging the stereo feeling.

Further, ML (t), MR (t) is multiplied by (1-α · A), which is the whole volume ML '(t), MR' (t) depending on the value of α.
In order to prevent fluctuations in the input signal, the application of (1-α · A) to the input signal is not limited (that is, it may not be applied if the volume may change).

The timing of updating .alpha..multidot.A is set at a certain time interval because the effect may fluctuate.

Further, although α represents the correlation amount, it is not used and α = X, B = (B + ΔB) when α <X, B = (B−ΔB) However, X may be calculated as a certain value ΔB: a certain amount of change, and B may be used instead of α. This is also for avoiding a phenomenon in which the effect fluctuates depending on the timing of updating α and avoiding erroneous determination.

In the present embodiment, an example in which the signal discriminating circuit 20 discriminates whether the input signal is voice or non-voice is shown by the frequency of occurrence of the silent section of the signal. The determination may be made by the inclination of the envelope, or a combination of this method and the determination method of this embodiment may be used.

Further, although the signal discriminating circuit 20 makes the judgment by taking the sum of the input signals, it is also possible to adopt a method of making the decision by the respective signals without taking the sum. The subsequent operation is similar to that of the first embodiment.

Next, a sound field signal reproducing apparatus according to the fourth embodiment of the present invention will be described with reference to the drawings. FIG. 7 is a block diagram showing the arrangement of a sound field signal reproducing apparatus according to the fourth embodiment. The parts having the same functions as those in the first and third embodiments are designated by the same reference numerals and detailed description thereof will be omitted.

In FIG. 7, L input to the input terminal 1
The ch signal ML (t) and the Rch signal MR (t) input to the input terminal 2 are each branched into two, one signal is given to the difference signal extractor 3 and the other signal is added by the adder. 22-1, 23
-1 is input. The output of the difference signal extractor 3 is given to the arithmetic circuits 4, 5, 6, 7.

In addition, the signal ML input to the input terminals 1 and 2
(t) and MR (t) are input to the signal determination circuit 20 that determines whether the input signal is a voice signal or a non-voice signal and the correlator 21 that determines the amount of correlation between the input signals. The output of arithmetic circuits 4, 5, 6, and 7 is a delay device
It is given to the adders 22-1, 23-1 via 8, 9, 10, 11. In addition, the signals S1 (t), S2 (t), S3 (t), S4 (t) are the respective operation circuits 4, 5, 6, 7
Is the output signal of.

The adder 22-1 includes an input terminal 2, a delay device 8 and a delay device.
The output signals of 10 are weighted and added by the results obtained by the signal determination circuit 20 and the correlator 21, and the adder 23-1 has an input terminal
This is a circuit for weighting and adding the output signals of 1, the delay device 9 and the delay device 11 with the results obtained by the signal determination circuit 20 and the correlator 21. The signals MR1 '(t) and ML'1 (t) are added by adders 22-1, 23-
This is the signal output from 1. The addition outputs of the adders 22-1 and 23-1 are output to the speakers 14 and 15, respectively.

The operation of the sound field signal reproducing apparatus according to the fourth embodiment having the above configuration will be described below in the first and third embodiments.
Only the parts different from the embodiment will be described.

In this embodiment, the signal judgment circuit 20 and the correlator 21 are
Except for the above, the configuration is similar to that of the first embodiment, and its operation is basically the same as that of the first embodiment. The operations of the signal judging circuit 20 and the correlator 21 are also the same as those in the third embodiment. However, the operation of the adders 22-1 and 23-1 is slightly different from that of the third embodiment.

The adder 22-1 performs addition as in the following equation.

[0112]

[Equation 31]

Similarly, the adder 23-1 performs addition as in the following equation.

[0114]

[Equation 32]

The subsequent operation is the same as in the first, second and third embodiments. Further, in the present embodiment, the signal determination circuit 20,
The configuration excluding the correlator 21 and the adders 22-1, 23-1 can be configured as in the second embodiment, and by doing so, the configuration can be simplified.

Next, a sound field signal reproducing apparatus according to the fifth embodiment of the present invention will be described with reference to the drawings. FIG. 8 is a block diagram showing the arrangement of a sound field signal reproducing apparatus according to the fifth embodiment. The parts having the same functions as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 8, L input to the input terminal 1
The ch signal ML (t) and the Rch signal MR (t) input to the input terminal 2 are each branched into two, one signal is given to the difference signal extractor 3 and the other signal is added by the adder. Input to 12 and 13. Further, the output of the difference signal extractor 3 is given to reflected sound producing circuits 24 and 25 for simulating a sound field of a hall or the like and producing reflected sound and reverberant sound. In addition, the reflected sound creation circuit 24,
The output of 25 is given to the arithmetic circuits 4, 5, 6, and 7. Arithmetic circuit 4,
The outputs of 5, 6, and 7 are given to the adders 12 and 13 via the delay units 8, 9, 10, and 11.

The adders 12 and 13 add the output signals of the input terminal 2, the delay device 8 and the delay device 10 at an arbitrary ratio, and the adder 13 outputs the output signals of the input terminal 1, the delay device 9 and the delay device 11. Add at any ratio. The addition outputs of the adders 12 and 13 are speakers 14 and
Output to 15.

With regard to the operation of the sound field signal reproducing apparatus in the fifth embodiment thus constructed, only the parts different from those of the first embodiment will be described below.

The difference signal obtained by the difference signal extractor 3 is applied to the reflected sound producing circuits 24 and 25. Then, the reflected sound creating circuits 24 and 25 create reflected sounds and reverberant sounds that simulate the sound field of a hall or the like.

9 (a) and 9 (b) respectively show a reflected sound producing circuit 2
The reflected sound sequences created in 4 and 25 are schematically shown, where the horizontal axis represents time and the vertical axis represents amplitude. These reflected sounds are obtained by actual measurement in a hall or simulation using the ray method.

FIG. 10 is a diagram for explaining the reflected sound producing circuits 24 and 25 for producing this reflected sound. In FIG. 10, 50
Is an input terminal, 51 is a delay device that delays by a time indicated by τi (i is Saphox, and the same applies below), 52 is a value called a tap coefficient indicated by X (i) and the signal output from each delay device. A multiplier (called a tap) that performs multiplication, 53 is an adder that sums up the signals output from each tap, and 54 is an output terminal. This display shows the case where a digital signal is used. When handling an analog signal, it is necessary to convert it into a digital signal by an A / D converter before inputting it to the reflected sound creating circuits 24 and 25. (In this embodiment, this A / D converter is omitted in the part where analog to digital conversion is necessary).

The reflected sound producing circuits 24 and 25 have the same structure as the arithmetic circuits 4, 5, 6, and 7 in the first embodiment, and are composed of the delay device 51 and the tap 52 as described above. In this case, a reflected sound sequence as shown in FIG. 9B is obtained. On the contrary, when it is desired to set the reflected sound as shown in FIG. 10B, the amplitude Xi and the delay time .tau.i are set to the tap and the delay device shown in FIG. This is actually a DRAM
(Dynamic Random Access Memory) and D
It is composed of an SP (digital signal processor) or the like. The reflected sound creating circuits 24 and 25 and the arithmetic circuits 4, 5, 6, and 7
Since the configurations are the same, it is possible to include the characteristics of the reflected sound producing circuits 24 and 25 in the characteristics of the arithmetic circuits 4, 5, 6, and 7.

As described above, by adding the reflected sound to the difference signal, it is possible to emphasize the surround feeling of the difference signal (surround signal).

Next, the output signals of the reflected sound producing circuits 24 and 25 are respectively branched into two and input to the arithmetic circuits 4, 5, 6 and 7. The subsequent operation is the same as in the first embodiment.

In the present embodiment, the parts other than the signal judging circuit 20, the correlator 21, and the reflected sound producing circuits 24 and 25 can be configured as in the second embodiment. By doing so, the configuration can be simplified.

Next, a sound field signal reproducing apparatus according to the sixth embodiment of the present invention will be described with reference to the drawings. FIG. 11 is a block diagram showing the configuration of the sound field signal reproducing apparatus in the sixth embodiment. The parts having the same functions as those of the first, third and fifth embodiments are designated by the same reference numerals and detailed description thereof will be omitted.

In FIG. 11, the Lch signal ML (t) input to the input terminal 1 and the Rch signal input to the input terminal 2 are input.
Signal MR (t) is divided into two, one signal is given to the difference signal extractor 3 and the other signal is added to the adders 23-1, 2
Input to 2-1.

In addition, the signal ML input to the input terminals 1 and 2
(t) and MR (t) are input to the signal determination circuit 20 that determines whether the input signal is a voice signal or a non-voice signal and the correlator 21 that determines the amount of correlation between the input signals.

The output of the difference signal extractor 3 is applied to reflected sound producing circuits 24 and 25 for simulating a sound field of a hall or the like and producing reflected sound and reverberant sound. The outputs of the reflected sound producing circuits 24 and 25 are given to the arithmetic circuits 4, 5, 6, and 7. The outputs of the arithmetic circuits 4, 5, 6, 7 are given to the adders 22-1, 23-1 via the delay units 8, 9, 10, 11. The adder 22-1 weights and adds the output signals of the input terminal 2, the delay device 8 and the delay device 10 with the results obtained by the signal determination circuit 20 and the correlator 21, and the adder 23-1 adds the output signal to the input terminal 1 , The output signals of the delay device 9 and the delay device 11 are weighted by the results obtained by the signal determination circuit 20 and the correlator 21 and added. Adder
The added outputs of 22-1 and 23-1 are output to the speakers 14 and 15, respectively.

The operation of this embodiment is basically the same as that of the fourth embodiment, but the signals processed by the arithmetic circuits 4, 5, 6, 7 are reflected by the difference signal of the difference signal extractor 3. The only difference is the signal added with the reflected sound in the creation circuits 24 and 25.

Next, a sound field signal reproducing apparatus according to the seventh embodiment of the present invention will be described with reference to the drawings. FIG. 12 is a block diagram showing the configuration of the sound field signal reproducing device in the seventh embodiment. The parts having the same functions as those of the first, third and fifth embodiments are designated by the same reference numerals and detailed description thereof will be omitted.

In FIG. 12, the Lch signal ML (t) input to the input terminal 1 and the Rch signal input to the input terminal 2 are input.
Signal MR (t) of each is divided into two, one signal is given to the difference signal extractor 3, and the other signal is added to the adders 23-2, 2
Input to 2-2.

In addition, the signal ML input to the input terminals 1 and 2
(t) and MR (t) are input to the signal determination circuit 20 that determines whether the input signal is a voice signal or a non-voice signal and the correlator 21 that determines the amount of correlation between the input signals.

The output of the difference signal extractor 3 is the reflected sound producing circuit 2
Output signal SSR of reflected sound creation circuits 24 and 25 given to 4 and 25
(t) and SSL (t) are output to the speakers 14 and 15 via the adders 22-2 and 23-2. MR2 '(t) and ML2' (t) are output signals of the adders 22-2 and 23-2.

With regard to the operation of the sound field signal reproducing apparatus in the seventh embodiment thus constructed, only the parts different from those of the first, third and fifth embodiments will be explained below.

Reflected sounds are added to the difference signals obtained by the difference signal extractor 3 in the reflected sound producing circuits 24 and 25. The adder 22-2 weights and adds the output signals of the input terminal 2 and the reflected sound creating circuit 24 with the results obtained by the signal determination circuit 20 and the correlator 21, and the adder 23-2 adds the input terminal 1 and the reflected signal. Sound creation circuit 2
The output signals of 5 are weighted by the results obtained by the signal determination circuit 20 and the correlator 21 and added. Similar to the third embodiment, the addition is performed by the following equation.

[0138]

[Expression 33]

[0139]

[Equation 34]

The addition outputs of the adders 22-2 and 23-2 are output to the speakers 14 and 15, respectively. Next, a sound field signal reproducing device according to an eighth embodiment of the present invention will be described with reference to the drawings. FIG. 13 is a block diagram showing the configuration of the sound field signal reproducing apparatus in the eighth embodiment. The detailed description of the parts having the same functions as those of the first, third, fifth and seventh embodiments will be omitted.

In FIG. 13, a multiplier 30 is a multiplication circuit for multiplying an input signal by -1, and an adder 56 is an input terminal 2
Is added to the output of the multiplier 30, and the adder 55 is a circuit of adding the signal given to the input terminal 2 and the signal given to the input terminal 1.

The reflected sound creating circuits 26 and 27 add the reflected sound to the output of the adder 55, and the reflected sound creating circuits 28 and 29 add the reflected sound to the output of the adder 56. Adder 22-3, 23-3
Is a circuit for weighting and adding the input signals using the values obtained by the signal judging means 20 and the correlator 21,
S1 '(t), S2' (t), S3 '(t), S4' (t) are reflected sound creation circuits 26, 27, 2
Output signals of MRs 8 ', MR3' (t) and ML3 '(t) are output signals of the adders 22-3 and 23-3, and are output from the speakers 14 and 15.

Regarding the operation of the sound field signal reproducing apparatus according to the eighth embodiment thus constructed, only the parts different from those of the first, third, fifth and seventh embodiments will be explained below.

The signal MR (t) input from the input terminal 2 is 2
It is divided into two, one is input to the adder 55 and the other is input to the adder 56. The signal MR (t) input to the input terminal 2 is also input to the adder 22-3. The signal ML (t) input to the input terminal 1 is branched into two, one is multiplied by -1 via the multiplier 30 and input to the adder 56, and the other is input to the adder 55. Also, input terminal 1
The signal ML (t) input to is also input to the adder 23-3.

The adder 56 adds MR (t) and -ML (t) and outputs the result, MR (t) -ML (t). That is, the multiplier 30 and the adder 56 form a difference signal extracting means. The output from the adder 56 is divided into two and is input to the reflected sound creating circuits 28 and 29, respectively, and the reflected sound is added to MR (t) -ML (t). , 23-3.

Similarly, the adder 55 adds MR (t) and ML (t), and outputs the result, MR (t) + ML (t). That is, the adder 55 constitutes a sum signal creating means.
The output from the adder 55 is divided into two and input to the reflected sound creating circuits 26 and 27, respectively, and the reflected sound is added to MR (t) + ML (t), and the result is added to the adder 22-3, respectively. , 23-3.

The adder 22-3 outputs the output signals S1 '(t) and S2' (t) of the reflected sound producing circuits 26 and 28 and the signal MR input to the input terminal 2.
(t) signal is input, and the adder 23-3 outputs the output signals S3 ′ (t) and S4 ′ (t) of the reflected sound creating circuits 27 and 29 and the signal ML (t) signal input to the input terminal 1. Input and add as in the third embodiment as in the third embodiment.

[0148]

[Equation 35]

[0149]

[Equation 36]

MR3 '(t) and ML3' (t) are radiated from the speakers 14 and 15. The reflected sound creating circuits 26, 27, 28 and 29 are the fifth
It has the same function as the reflected sound producing circuits 24 and 25 described in the embodiment.

By thus providing the reflected sound creating circuit and convolving the reflected sound with the difference component of the input signal, it is possible to reproduce a sound field with a sense of natural expanse and a sense of reality without antisense. . In addition, by providing two reflection sound generation circuits for each channel, it is possible to reproduce a sound field in which the signals output from the two speakers 14 and 15 are different in the convoluted reflection sound. Sound can also be added in stereo. Further, by changing the delay amount of the delay device and the coefficient of the multiplier in the reflected sound creating circuit, it is possible to generate a plurality of types of sound fields such as a sound field with rich resonance and a sound field with few reflected sounds.

Next, a sound field signal reproducing apparatus according to the ninth embodiment of the present invention will be described with reference to the drawings. FIG. 14 is a block diagram showing the arrangement of a sound field signal reproducing apparatus according to the ninth embodiment. The detailed description of the parts having the same functions as those of the first, third, fifth and eighth embodiments will be omitted.

In FIG. 14, a multiplier 31 is a multiplication circuit for multiplying the input signal by -1, and adders 22-4 and 23-4 are input using the values obtained by the signal judging means 20 and the correlator 21. MR4 'is a circuit that weights and adds signals.
(t) and ML4 '(t) are output signals of the adders 22-4 and 23-4. or,
Signals SS1 (t) and SS3 (t) are output signals of adder 12-1 and signal SS2
(t) is the output signal of the multiplier 31, and signal SS4 (t) is the adder 13-1.
Is the output signal of.

With regard to the operation of the sound field signal reproducing apparatus in the ninth embodiment thus constructed, only the parts different from those of the third, fifth and eighth embodiments will be explained below.

The output signals of the reflected sound producing circuits 26, 27, 28 and 29 are input to the adders 12-1 and 13-1, respectively. Adder 12-
In 1, the output from the reflected sound creation circuits 26, 28 is added,
The result is divided into two, one is input to the adder 22-4 and the other is input to the adder 23-4. The adders 13-1 add the outputs from the reflected sound producing circuits 27 and 29, divide the result into two, and input one to the multiplier 31 and the other to the adder 23-4. . The multiplier 31 multiplies the output from the adder 13-1 by -1 and inputs the result to the adder 22-4.

The adder 22-4 outputs the output signal SS1 of the adder 12-1.
(t), the output signal SS2 (t) of the multiplier 31 and the signal MR (t) signal input to the input terminal 2 are input, and the adder 23-4 is added by the adder 1
The output signal SS3 (t) of 2-1 and the output signal SS4 (t) of the adder 13-1 and the signal ML (t) signal input to the input terminal 1 are input and the same as in the third embodiment. The addition as in the following formula is performed.

[0157]

[Equation 37]

[0158]

[Equation 38]

MR4 '(t) and ML4' (t) are speakers 14, 15
Emitted more. In this way, the outputs from the reflected sound producing circuits 26 and 28 are output from the speaker 14 in phase, but the outputs from the reflected sound producing circuits 27 and 29 are output from the speaker 15 in antiphase.

As described above, by adding the reflected sound to each of the difference signal and the sum signal of the stereo signals, which are reproduced in the same phase and those reproduced in the opposite phase, the sense of spread due to the reverse phase reproduction is added. Also, the uncomfortable sense of reverse phase can be softened by addition with the signal reproduced in phase.

[0161]

As described above, according to the sound field signal reproducing apparatus of the present invention, the sound signal can be clearly reproduced, and the natural spread with a realistic sensation can be reproduced with a simple system configuration.

[Brief description of drawings]

FIG. 1 is a hardware block diagram of a sound field signal reproducing device according to a first embodiment of the present invention.

FIG. 2 is a block diagram illustrating the principle of the arithmetic circuit of the sound field signal reproducing device according to the first embodiment of the present invention.

FIG. 3 is a block diagram illustrating a configuration of an arithmetic circuit of the sound field signal reproducing device according to the first embodiment of the present invention.

FIG. 4 is a hardware block diagram of a sound field signal reproducing device according to a second embodiment of the present invention.

FIG. 5 is a hardware block diagram of a sound field signal reproducing device according to a third embodiment of the present invention.

FIG. 6 is a diagram illustrating the principle of a signal determination circuit of a sound field signal reproducing device according to a third embodiment of the present invention.

FIG. 7 is a hardware block diagram of a sound field signal reproducing device according to a fourth embodiment of the present invention.

FIG. 8 is a hardware block diagram of a sound field signal reproducing device according to a fifth embodiment of the present invention.

FIG. 9 is a diagram for explaining a reflected sound adding method of a sound field signal reproducing device according to a fifth embodiment of the present invention.

FIG. 10 is a diagram illustrating a configuration of a reflected sound creating circuit of a sound field signal reproducing device according to a fifth embodiment of the present invention.

FIG. 11 is a hardware block diagram of a sound field signal reproducing device according to a sixth embodiment of the present invention.

FIG. 12 is a hardware block diagram of a sound field signal reproducing device according to a seventh embodiment of the present invention.

FIG. 13 is a hardware block diagram of a sound field signal reproducing device according to an eighth embodiment of the present invention.

FIG. 14 is a hardware block diagram of a sound field signal reproducing device according to a ninth embodiment of the present invention.

FIG. 15 is a hardware block diagram of a conventional sound field signal reproducing device.

[Explanation of symbols]

 1, 2 Input terminals 3 Difference signal extractor 4, 5, 6, 7 Arithmetic circuit 8, 9, 10, 11 Delay device 12, 13 Adder 14, 15 Speaker 16 Listener

Claims (8)

[Claims] 1. Input means for inputting a 2ch signal, signal extraction means for obtaining a difference or sum of two signals input to the input means, and operation means for performing a convolution operation for localizing a sound image in an arbitrary direction. A delay means for delaying the output signal of the arithmetic means by an arbitrary time; an adding means for adding the output signal of the delay means and the signal input to the input means at an arbitrary ratio; and an output of the adding means. A sound field signal reproducing device having an output means for outputting a signal to the outside. 2. Correlation between an input means for inputting a 2ch signal, a signal determining means for determining whether the 2ch signal input to the input means is a voice signal or a non-voice signal, and a signal input to the input means. Correlation degree calculating means to be obtained and input 2
Signal extraction means for obtaining the difference or sum of two signals, delay means for delaying the output signal of the signal extraction means by an arbitrary time, and the signal discrimination between the output signal of the delay means and the signal input to the input means A sound field signal reproducing apparatus having an adding means for weighting and adding the results obtained by the means and the correlation degree calculating means, and an output means for outputting the output signal of the adding means to the outside. 3. Correlation between an input means for inputting a 2ch signal, a signal determining means for determining whether the 2ch signal input to the input means is a voice signal or a non-voice signal, and a signal input to the input means. Correlation degree calculating means to be obtained and input 2
Signal extraction means for obtaining the difference or sum of two signals, operation means for performing convolution operation for localizing a sound image in an arbitrary direction, delay means for delaying an output signal of the operation means for an arbitrary time, and the delay means Output signal and the signal input to the input means are weighted from the results obtained by the signal determination means and the correlation degree calculation means and added, and the output signal of the addition means is externally output. A sound field signal reproducing device having output means for outputting. 4. Input means for inputting a 2ch signal, signal extraction means for obtaining a difference or sum of two signals input to the input means, and reflected sound or reverberation added to an output signal of the signal extraction means. Signal processing means, a computing means for performing a convolution operation for localizing a sound image in an arbitrary direction, a delay means for delaying an output signal of the computing means by an arbitrary time, an output signal of the delay means and the input means. A sound field signal reproducing apparatus having an adding means for adding the signals input to the device at an arbitrary ratio and an output means for outputting the output signal of the adding means to the outside. 5. A correlation between an input means for inputting a 2ch signal, a signal determining means for determining whether the 2ch signal input to the input means is a voice signal or a non-voice signal, and a correlation between the 2ch signal input to the input means. And a signal processing means for adding reflected sound or reverberation to the output signal of the signal extracting means, A calculation unit that performs a convolution calculation to localize a sound image in an arbitrary direction, a delay unit that delays an output signal of the calculation unit by an arbitrary time, and an output signal of the delay unit and a signal input to the input unit. A sound field signal having an adding means for weighting and adding the results obtained by the signal determining means and the correlation calculating means, and an output means for outputting the output signal of the adding means to the outside. Reproducing apparatus. 6. An input means for inputting a 2ch signal, a signal determining means for determining whether the 2ch signal input to the input means is a voice signal or a non-voice signal, and a correlation degree for obtaining a correlation between the input 2ch signals. The calculation means, the difference signal extraction means for obtaining the difference between the two signals input to the input means, the signal processing means for adding reflected sound or reverberation to the output signal of the difference signal extraction means, and the signal processing means. An adding means for weighting and adding the output signal and the signal input to the input means from the results obtained by the signal determining means and the correlation degree calculating means, and outputting the output signal of the adding means to the outside. Sound field signal reproducing device having an output means for 7. An input means for inputting a 2ch signal, a signal discriminating means for discriminating whether the 2ch signal input to the input means is a voice signal or a non-voice signal, and a correlation degree for obtaining a correlation between the input 2ch signals. The calculation means, the difference signal extraction means for calculating the difference between the two signals input to the input means, the sum signal generation means for calculating the sum of the two signals input to the input means, and the difference signal extraction means. The first signal processing means for adding reflected sound or reverberation to the output signal, the second signal processing means for adding reflected sound or reverberation to the output signal of the sum signal generating means, and the first signal processing means An adding unit for weighting and adding the output signal, the output signal of the second signal processing unit, and the signal input to the input unit from the results obtained by the signal determining unit and the correlation degree calculating unit. And the addition means Sound field signal reproducing apparatus and an output means for outputting a force signal to the outside. 8. An input means for inputting a 2ch signal, a signal discriminating means for discriminating whether the 2ch signal input to the input means is a voice signal or a non-voice signal, and a degree of correlation for obtaining a correlation between the input 2ch signals. The calculation means, the difference signal extraction means for calculating the difference between the two signals input to the input means, the sum signal generation means for calculating the sum of the two signals input to the input means, and the difference signal extraction means. First signal processing means for adding reflected sound or reverberation to the output signal, second signal processing means for adding reflected sound or reverberation to the output signal of the sum signal generation means, and first signal processing means First adding means for adding an output signal and an output signal of the second signal processing means, and first and second signal dividing means for dividing the output signal from the first adding means into two, respectively. Of the first and second signal dividing means Two second adding means for weighting and adding the force signal and the signal input to the input means from the results obtained by the signal determining means and the correlation degree calculating means; and the second adding means. Output means for outputting the output signal of the means to the outside, and one second adding means of the second adding means is one of the two output signals of the first and second signal dividing means. A sound field signal reproducing device, characterized in that one of the signals is multiplied by -1 and then added.