JP2000224699A - Recording medium recording sound image localization processing program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an excellent surround effect with a simple configuration by acting a side localization means that outputs a signal to localize a surround signal to a side of a listener to a right and/or a left speaker, applying equal delay to a front left and a front right signal to a delay time of the side localization means and outputting the result to the left and the right speaker. SOLUTION: Surround left right signals SL, SR are given to left and right speakers via a side localization means 12 to localize the surround left right signals SL, SR to a side of a listener as virtual speakers. On the other hand, front left and right signals FL, FR are given to delay means 14L, 14R, which give an equal delay time to that by the side localization means 12 and adder means 16L, 16R, adder means 18L, 18R sum the result to an output of the side localization means and the sum is given to the left right speakers thereby compensating the delay among the front left, right signals FL, FR and the surround left, right signals SL, SR.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001] 1. Field of the Invention [0002] The present invention relates to a sound image localization processing technique, and more particularly, to a sound image localization processing technique capable of obtaining an excellent surround effect with a simple configuration.

2. Description of the Related Art Conventionally, a loudspeaker is provided by two
Various sound image localization processing techniques are proposed to obtain the sound effect.
Have been. Typically, a sound image localization processing as shown in FIG.
A processing device has been proposed in Japanese Patent Application Laid-Open No. 8-265899.
I have. This device includes left and right swaths arranged in front of the listener 2.
From the virtual speakers XL and XR by the speakers 4L and 4R
This is to make a sound emitted. this
With the device, even if there are only two speakers,
Also listener 2 as if there were speakers XL and XR behind
You can appeal to your hearing. In the device of FIG.
Using four filters 6a, 6b, 6c and 6d,
This has been achieved. Transfer function H1 of four filters
1, H12, H21 and H22 are as follows.
It is.Here, h_LLIs the left of the listener 2 from the speaker 4L
Transfer function to the ear 2L, h_LRIs the speaker 4L
Transfer function from the listener 2 to the right ear 2R, h_RLIs
The transfer function from the speaker 4R to the left ear 2L of the listener 2
Yes, h_RRIs from the speaker 4R to the right ear 2R of the listener 2.
Is the transfer function at_L'LIs received from the virtual left speaker.
Transfer function to the left ear of the listener, h_L'RIs a virtual left button
Transfer function from the peaker to the listener's right ear, h
_R'LIs the transfer function from the virtual right speaker to the listener's left ear.
A number and h_R'RIs heard from the virtual right speaker
Transfer function to the right ear of the person. By the way, speaker 4
L and 4R and the virtual speakers XL and XR.
Both are symmetrical with respect to the front axis 8 of the listener 2.
In the above equation, h_{L L}= H_RR, H_LR= H_RL,
h_L'L= H_R'R, And h_L'R= H_R'L Is established
I do. Therefore, H11 = H22 and H12 = H21.
As shown in FIG.
Can be realized. Here, the filters 10a and
Transfer function H of_SUMAnd H_DIFIs the following formula
It is represented by H_SUM= (H_{a '}+ H_{b '}) / (H_a+ H_b) H_DIF= (H_{a '}-H_{b '}) / (H_a-H_bNote that h_a= H_LL= H_RR, H_b= H_LR= H_RL,
h_{a '}= H_L'L= H_{R 'R}, H_{b '}= H_L'R= H
_R'LIt is. Thus, in the case of a symmetrical arrangement
Uses a simple configuration to create a sound image at a virtual speaker position.
Can be localized.

However, in the above prior art, although a surround effect can be obtained by two speakers, no consideration is given to increasing the stage width determined by the arrangement interval of the front speakers. Has not been made. Therefore, in a device (for example, a television) in which a speaker is built into the device and it is difficult to increase the position interval between the speakers, there is a problem that the front stage width is insufficient and a sufficient surround effect cannot be obtained. SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to provide a sound image localization processing technique which can obtain an excellent surround effect with a simple configuration.

The present invention is a recording medium recording a sound image localization processing program, which includes causing a computer to execute the following processing: Functioning the side localization means for outputting a signal for localizing the surround signal to the side of the listener to the right speaker and / or the left speaker; inputting the front left signal and the front right signal, and On the other hand, the delay means for outputting to the left speaker and the right speaker after a delay equal to the delay time of the lateral localization means is performed; and the front localization means is further provided with a forward left signal and / or a forward right signal. By providing a signal, a front left signal and a front right signal are localized between each of the left and right speakers and the side of the listener. In another embodiment of the present invention, the sound image localization processing program includes causing a computer to execute the following processing: functioning a difference signal generating means for generating a difference signal between a front left signal and a front right signal. Receiving the difference signal generated by the difference signal generating means,
Functioning first delay means for giving a delay equal to the delay time of the filter means to the front left signal; delaying the filter means to the front right signal Activating second delay means for providing a delay equal to time;
Functioning a central mono signal generating means for adding the output of the delay means and the output of the second delay means; adding the output of the filter means to the central mono signal and providing the result to the left or right speaker And a subtraction output means for subtracting the output of the filter means from the central mono signal to generate a signal to be provided to a left or right speaker. Here, the transfer function Hs is Hs = (h _{a '-h
b ')} represented by _{/ (h a -h b),} h a' is the transfer function from the right virtual speaker to right ear of the listener, h
_{b 'is} the transfer function from the left virtual speaker to the right ear of the listener, h _a is the transfer function from the right speaker to the right ear of the listener, and, h _b is from left to right speaker of the listener This is the transfer function to the ear. In still another embodiment of the present invention, a sound image localization processing program includes causing a computer to execute the following processing: a signal obtained by performing coefficient processing on a front left signal by a first coefficient; Functioning first adding means for adding a signal subjected to coefficient processing using a first coefficient to a signal; a signal obtained by performing coefficient processing using a second coefficient on a front left signal; Functioning a second adding means for subjecting the signal to coefficient processing using a second coefficient and adding the signal whose phase has been inverted; a signal obtained by subjecting a surround left signal to coefficient processing using a third coefficient And a third adding means for adding a signal obtained by subjecting the surround right signal to coefficient processing by a third coefficient; a signal obtained by subjecting the surround left signal to coefficient processing by a fourth coefficient To function fourth adding means for adding the signal obtained by phase inversion by performing coefficient processing according to the fourth coefficient with respect to the surround right signal; output and said third of said first addition means
Functioning a fifth addition means for adding the output of the addition means of the second addition means; functioning a sixth addition means for adding the output of the second addition means to the output of the fourth addition means; Causing the first filter means to perform a filtering process on the output of the fifth adding means substantially according to the transfer function H _SUM ; Functioning a second filter means for _{performing a} filtering process according to _DIF ; a first delay processing means for performing a delay process on a front left signal to compensate for a delay time caused by the first and second filter means; Functioning; functioning second delay processing means for performing delay processing on a front right signal in order to compensate for the delay time caused by the first and second filter means; A signal obtained by adding a signal obtained by subjecting the output of the first delay processing means to coefficient processing by a sixth coefficient and a signal obtained by subjecting the output of the second delay processing means to coefficient processing by a sixth coefficient to be added. Causing the addition means of the seventh delay means to function; a signal obtained by subjecting the output of the first delay processing means to coefficient processing by a fifth coefficient; the output of the seventh addition means; and the output of the first filter means. Functioning an eighth adding means for adding a signal subjected to coefficient processing using a seventh coefficient to a signal subjected to coefficient processing using a seventh coefficient to an output of the second filter means; The second
A signal obtained by subjecting the output of the delay processing means to coefficient processing by the fifth coefficient, the output of the seventh adding means, and the output of the first filter means to be subjected to coefficient processing by the seventh coefficient. Functioning ninth addition means for adding the signal and a signal obtained by performing a coefficient process using a seventh coefficient on the output of the second filter means and inverting the phase thereof;
The output of the eighth adding means is an output for providing to a left speaker, and the output of the ninth adding means is an output for providing a right speaker. Here, the transfer function H
_SUM and _{H DIF} has the formula: _{H SUM = (h a '+} h b') / (h a + h b) H DIF = (h a '-h b') / (h a -h b) h _{a = h LL = h RR,} h b = h LR = h RL, h a '
= _{H L'L} = _{h R'R,} a _{h b '= h L'R =} h R'L, h LL is a transfer function from the left speaker to the left ear of the _{listener, h LR} is a left speaker H _RL is the transfer function from the right speaker to the listener's left ear, h _RR is the transfer function from the right speaker to the listener's right ear, h h _{L′ L} is a transfer function from the virtual left speaker to the listener's left ear, and h _{L′ R}
Is the transfer function from the virtual left speaker to right ear of the listener, h _R'L is a transfer function from the virtual right speaker to the left ear of the listener, and, h _R'R is received from the virtual right speaker This is the transfer function to the right ear of the listener. In a preferred embodiment, the recording medium of the present invention is a CD, a CD-R,
It is selected from CD-ROM, DVD, DVD-ROM, MD or floppy disk.

(Embodiment 1) A sound image localization processing apparatus to which a preferred embodiment of the present invention is applied will be described. FIG. 1 shows a digital signal processor (DSP) 2 as a means for executing a program used in the present invention.
FIG. 2 is a block diagram showing a hardware configuration when using No. 2. According to this device, the front left signal FL, the front right signal FR, the surround left signal SL, and the surround right signal S
Give R as an input, signal _{L OU T} for the left speaker 4L
And a signal R _OUT for the right speaker 4R. The signals FL, FR, SL, and SR are input to a multi-channel surround decoder (not shown) to perform decoding by inputting a digital bit stream or an analog signal obtained by digitizing an analog signal by an A / D converter to a surround encoded digital bit stream. And provided to the DSP 22. Multi-channel surround decoder
It may be independent of the DSP 22, or may be built in the DSP 22. The DSP 22 performs processing according to the program recorded in the memory 26, and generates a signal L _OUT for the left speaker and a signal R _OUT for the right speaker.
These signals are converted into analog signals by the D / A converter 24 and supplied to the speakers 4L and 4R. Processing such as storage of a program in the memory 26 is performed by the microprocessor 20. Memory 26
The processing performed by the DSP 22 based on the program shown in FIG.
Shows the signal flow format. Surround left signal SL
The surround right signal SR is provided to a lateral localization unit (for example, a shuffler type filter) 12. The output from the lateral localization means 12 is transmitted to speakers 4L and 4R.
, The surround left signals SL and SR can be localized to the side of the listener 2 as virtual speakers XL and XR, as shown in FIG. on the other hand,
The front left signal FL and the front right signal FR are subjected to delay processing by delay means 14L and 14R, respectively, added to the output of the lateral localization means 12 by addition processing 18L and 18R, and given to the speakers 4L and 4R. Can be The delay unit 14L gives a delay time equal to the delay by the side localization unit 12 and the addition unit 16L. The delay unit 14R includes the side localization unit 12 and the addition unit 16
Give a delay time equal to the delay due to R. This allows
The delay between the front left signal FL and the front right signal FR and the surround left signal SL and the surround right signal SR can be compensated. Thus, the front left signal FL and the front right signal FR are provided to the speakers 4L and 4R, respectively, and form a sound image at the positions of the speakers 4L and 4R. Further, the front left signal FL and the front right signal FR are provided to the lateral localization means 12 via the addition means 16L and 16R. Thereby, the front left signal F
L is not only the position of the speaker 4L, but also the virtual speaker X
It is also localized at the position of L. As a result, the front left signal FL becomes
As shown in FIG. 3, it is located at a position XXL between the two positions. Similarly, the front right signal FR is located at the position XXR. Therefore, the localization positions of the front left signal FL and the front right signal FR can be extended outside the positions of the speakers 4L and 4R. That is, even if the interval between the front speakers 4L and 4R is small, the width of the front stage can be reduced. Further, since the processing for sharing the side localization means 12 is performed as a filter for performing the localization processing for increasing the width of the front stage, this can be realized with a simple configuration. Delay means 1 if necessary
Front left signal FL and front right signal FR applied to 4L and 14R, and front left signal FL applied to side localization means 12
By changing the ratio between the front left signal FL and the front right signal FR, the localization position XXL of the front left signal FL and the localization position XXR of the front right signal FR can be moved between the speakers 4L and 4R and the virtual speakers XL and XR. it can. (Embodiment 2) A sound image localization processing apparatus to which another embodiment of the present invention is applied will be described. According to this device, the center signal C, the front left signal FL, the front right signal FR, the surround left signal SL, the surround right signal SR, and the bass signal LF
E as inputs and connect these speakers 4L and 4R
And the subwoofer speaker 4S. Hardware configuration for realizing the device using the DSP22, except that the output SUB _{O UT} of input and subwoofer speaker signal of the center signal C and the bass signal LFE are provided is similar to that of FIG. 1 . Note that, in the present embodiment, as shown in FIG. 4, a case where the speakers 4L and 4R are symmetrically arranged with respect to the front axis 8 of the listener 2 and the virtual speakers XL and XR are symmetrically arranged. explain. Since the bass output from the woofer speaker 4S has a long wavelength and weak directivity, it can be arranged at any appropriate position. Processing performed by the DSP 22 based on the program in the memory 26
FIG. 5 shows a signal flow format. The surround left signal SL and the surround right signal SR are provided to a lateral localization unit (for example, a shuffler type filter) 12. The output from the lateral localization means 12 is transmitted to the speakers 4L and 4L.
By giving R, the surround left signals SL and SR can be localized as virtual speakers XL and XR beside the listener 2 as shown in FIG. On the other hand, the center signal C is added to the front left signal FL and the front right signal FR by the adding means 44 and 46, respectively. Next, these signals are subjected to delay processing by delay means 14L and 14R, respectively, and then applied to speakers 4L and 4R. As a result, FIG.
The center signal can be localized at the position XC. By using such a central signal C, it is possible to prevent a hollow phenomenon (a phenomenon in which the thickness of sound near the center is lost) when the front stage is expanded. The processing using the central signal C is performed in the vicinity of the center, such as in the case of movie sound.
This is particularly effective when a lot of important information is included. Further, the bass signal LFE is output from the filter 12.
After performing a delay process 30 for compensating for the delay of the _SUM and the 12 _DIF, the signal is added to the front left signal FL and the front right signal FR via addition processes 18L and 18R. Thereafter, the addition processing 54 adds the front left signal FL and the front right signal FR, and the low-pass filter 60 extracts only the bass part from the added signal. The low-pass filter LFE that has been subjected to the delay processing 30 is added to the output of the low-pass filter by the addition processing 62 to obtain a signal SUB _OUT to be provided to the woofer speaker 4S. further,
In the present embodiment, high-pass filter processing 56 and 58 are performed to cut low-frequency parts, and the speaker signal L
_OUT and R _OUT are obtained. According to the present embodiment, even when the speakers 4L and 4R cannot sufficiently reproduce bass, a sound field with a sense of reality can be obtained by the woofer speaker 4S. (Embodiment 3) A sound image localization processing apparatus to which still another embodiment of the present invention is applied will be described. According to this device, the MS system (mono-mode) is controlled by the two front speakers.
Virtual speaker X required for stereo playback of side method)
Implement M, XL, XR. That is, according to this device, the front left signal FL and the front right signal FR are input,
In order to localize the sound image at the positions of the virtual speakers XM, XL and XR in FIG. 6, signals L _OUT and R _OUT given to the speakers 4L and 4R are output. In addition, also in this embodiment, as shown in FIG. 6, the speakers 4L and 4R are symmetrically arranged with respect to the front axis 8 of the listener 2.
The case where the virtual speakers XL and XR are symmetrically arranged will be described. The hardware configuration when this device is implemented using the DSP 22 is basically the same as that in FIG. Inputs C, SL, SR and L as required
An FE may be provided. FIG. 7 shows a process performed by the DSP 22 based on the program stored in the memory 26 in a signal flow format. In the subtraction processing 70, a difference signal between the front left signal FL and the front right signal FR is calculated. This difference signal is
90-degree direction localization processing (typically, filter means) 80
(Representatively, a filtering process). Thereby, the S component is calculated. In addition, the front left signal FL and the front right signal FR are subjected to delay processing 78L and 78R in order to compensate for the delay of the signal subjected to the 90-degree localization processing. After the delay processing, the front left signal FL and the front right signal FR are added in the addition processing 72 to generate an M component (central mono component). In addition processing 74, it is added to the M component and S component, the signal _{L OUT} for the left speaker 4L is obtained. Also, subtraction processing 7
In 6, the S component is subtracted from the M component, and a signal R _OUT for the right speaker 4R is obtained. These signals are
When given to the speakers 4L and 4R, the M signal is localized at the intermediate XM between the speakers 4L and 4R, and the S signal is
, And the -S signal is located on the right side XR of the listener 2. In this way, stereo reproduction with a surround effect by the MS method can be realized only by the two speakers 4L and 4R. In the present embodiment, the above-described processing can be performed by one 90-degree direction localization processing (filter means) 80 for the following reason. In FIG. _{6, h a = h LL =} h RR, h
and _{b = h} LR = _{h RL,} defining a transfer function _{H MS} 90 ° direction localization processing 80 as follows.

(Equation 1) For the front left signal FL and the front right signal FR, the signal M
And S are defined as follows:

(Equation 2) The MS type localization process only needs to satisfy the following equation.

(Equation 3) _Here, unless ^h a ² _-h ^b 2 is 0, _{[H MS]}
Is obtained by calculating the following equation.

(Equation 4) When you solve this

(Equation 5) Is obtained. Here, when the distance between the actual speakers 4L and 4R is _small, h M, _{h a} and _{h b} are regarded as _equal, it can be a H M = 1/2. Therefore, one 90 ° direction localization processing 80 (the filtering means) having a transfer function of H _s only, can be realized.
As described above, according to the present embodiment, MS-type stereo reproduction can be realized with two speakers using only one filter unit. Therefore, simplification of the filtering process can be achieved. Further, as shown in FIG. 7, in the present embodiment, the delay processes 78L and 78L
8R-treated front left signal FL and front right signal FR
With the predetermined coefficient k3, respectively.
_OUT and R _OUT are added. Therefore, by adjusting the coefficient k3, the sensory width of the front stage can be changed. (Embodiment 4) A sound image localization processing apparatus to which still another embodiment of the present invention is applied will be described. The hardware configuration of this device is the same as that of the second embodiment. The processing performed by the DSP 22 based on the program in the memory 26 is shown in FIG.
Shows the signal flow format. 8, after the center signal C is subjected to coefficient processing 208a and 208b, it is added to the front left signal FL and the front right signal FR by addition processing 44 and 46. The coefficient processing 20
8a and 208b, arbitrarily set 0 to 0
Multiplied by a coefficient in the range of 1 (the same applies hereinafter). The outputs of the addition processes 44 and 46 are delayed by the delay processes 14L and 1
4R. In the delay processing 14L and 14R,
9 of the surround left signal SL and the surround right signal SR
A delay for compensating a delay due to the 0-degree direction localization processing is performed. The delay processing can be easily realized by the DSP 22 writing data to the memory 26 and reading the data after the elapse of the delay time. After the outputs of the delay processes 14L and 14R are multiplied by the coefficient k5 in the coefficient processes 205a and 205b, they are provided as second output elements to the addition processes 50 and 52. In addition, delay processing 14L
And 14R are output by coefficient processing 206a and 206R.
In b, after being multiplied by the coefficient k6, the result is added in the addition process 48, and is given to the addition processes 50 and 52 as a third output element. The front left signal FL and the front right signal FR are multiplied by coefficients k2 and -k2 by coefficient processes 202a and 202b, and then added in an addition process 42. Note that multiplying by a negative coefficient means inverting the phase. Therefore, in the addition process 42, as a result, a difference signal between the front left signal FL and the front right signal FR, both of which have been subjected to coefficient processing, is obtained. Surround left signal SL and surround right signal SR
Is calculated by the coefficient processing 204a and 204b.
After being multiplied by 4, -k4, they are added in an adding process 34. The output of the addition processing 34 is added to the output of the addition processing 42 described above in the addition processing 38, and is provided to the 90-degree direction localization processing _12DIF . Forward left signal FL
And the front right signal FR are also multiplied by a coefficient k1 by coefficient processing 201a and 201b,
It is added at 0. The surround left signal SL and the surround right signal SR are also subjected to coefficient processing 203a and 2
After multiplying the coefficient k3 by the coefficient k3b, the addition processing 32
Are added. The output of the addition processing 32 is added to the output of the addition processing 40 described above in the addition processing 36, and is provided to the 90-degree direction localization processing 12 _SUM . 9
The 0-degree direction localization processing 12 _SUM and the 90-degree direction localization processing 12 _DIF include the following transfer functions H _SUM and H _DIF.
Is performed. _{H SUM = (h a '+} h b') / (h a + h b) H DIF = (h a '-h b') / (h a -h b) In _{addition, ha = h LL = h RR} , -h _b = _hLR =
_{h RL, = h a '=} h L'L = h R'R, h b' = h
_{L′ R} = _hR′L . 90-degree direction localization processing 12
The output of the _SUM is multiplied by a coefficient k7 by a coefficient process 207a, and given to the addition processes 50 and 52 as a first output signal element. Also, the 90-degree direction localization processing 12
The output of the _DIF is multiplied by a coefficient k7 by a coefficient process 207b, provided to the addition process 50 as a first output signal element, multiplied by a coefficient −k7 by a coefficient process 207C, and added as a first output signal element. 52. After the bass signal LFE is subjected to the delay processing 30,
The result is multiplied by the coefficient k9 by the coefficient processing 209a and provided to the addition processings 50 and 52. The outputs of the addition processes 50 and 52 are multiplied by the coefficient k11 by the coefficient processes 211a and 211b,
6 and 58. The high-pass filter processing 56 and 58 can be selected to be on or off (that is, whether to perform a filtering operation or a through-pass). Outputs of the high-pass filter processes 56 and 58 become a left speaker signal L _OUT and a right speaker signal R _OUT . The outputs of summing operations 50 and 52 are also processed by coefficient operations 212a and 212b to obtain coefficient k
After being multiplied by 12, they are added in an adding process 54. The output of the addition processing 54 is a low-pass filter processing 60
Given to. The output of the low-pass filter processing 60 is obtained by multiplying the delay processing 30 by a coefficient k10 (coefficient processing 210
a) in the addition process 62. Addition processing 6
The output of 2 is a signal SUB _OUT for a woofer speaker. According to the present embodiment, while being one device,
By simply changing the count value of each coefficient process, various reproduction methods, surround effects, and the like can be easily selected. Hereinafter, some specific examples of the values of the respective coefficients k1 to k12 shown in FIG. First, a description will be given of a case where two-channel stereo reproduction is realized by two speakers 4L and 4R (a woofer speaker 4S is also used in some cases). The input signals in this case are the front left signal FL and the front right signal FR. k1, k2, k3, k4, k6,
k7, k8, k9 and k10 are set to substantially 0, and k5
When k11 and k11 are substantially non-zero values, normal two-channel stereo is obtained. In this case, 4 in FIG.
The sound image is localized at the positions of L and 4R. k3, k4, k
5, k6, k8, k9 and k10 are substantially 0,
When k1, k2, k7, and k11 are set to substantially non-zero values, the virtual speakers XL and XR shown in FIG.
Can be localized. k3, k4, k6,
Let k8, k9 and k10 be substantially 0, and k1, k
When k2, k5, k7 and k11 are substantially non-zero values, the virtual speakers XXL and XX shown in FIG.
It can be localized at the position of R. In this case, the localization position can be moved by adjusting the value of k5. Let k1, k3, k4, k5, k8, k9 and k10 be substantially 0, and k2, k6, k7 and k
When 11 is set to a value other than substantially 0, stereo reproduction by the MS method shown in FIG. 6 can be realized.
When k1, k3, k4, k8, k9, and k10 are substantially 0 and k2, k5, k6, k7, and k11 are substantially non-zero, M shown in FIGS.
-S stereo reproduction can be realized. Further, the sound image can be localized at the positions of the real speakers 4L and 4R. In any of the above cases, when the woofer speaker 4S is used, k12 may be set to substantially not zero. Next, a description will be given of a case of realizing 4-channel surround-sound reproduction by using two speakers 4L and 4R (a woofer speaker 4S may be used in some cases). The input signals in this case are the front left signal FL, the front right signal FR, the surround left signal SL, and the surround right signal SR. k1, k2,
Let k6, k8, k9 and k10 be substantially 0, k
When 3, k4, k5, k7, and k11 are substantially non-zero, the front left signal FL is localized on the speaker 4L, the front right signal FR is localized on the speaker 4R, and the surround left signal SL is XL. , And the surround right signal SR is localized to XR. Let k6, k8, k9 and k10 be substantially 0, and k1, k2, k3, k4, k5, k7 and k11
1 and FIG. 2 when
Can be realized. In this case, by changing k2 and / or k5,
Localization position XXL of front left signal FL and front right signal FR
And XXR can be moved. In any of the above cases, when the woofer speaker 4S is used, k12 may be set to substantially not zero. Next, in addition to the above four-channel surround, the center signal C
And a case where the bass signal LFE is input. k1, k2, k6, k9 and k12 are substantially 0
And k3, k4, k5, k7, k8, k10 and k
When 11 is a value that is not substantially 0, X in FIG.
4. Localize to C, 4L, 4R, XL, XR and XS
A one-channel surround system can be realized. k6, k9
And k12 are set to substantially 0, and k1, k2, k3, k
In the case where 4, k5, k7, k8, k10, and k11 are substantially non-zero, XC, XXL, XX in FIG.
A 5.1-channel surround system in which R, XL, XR, and XS are localized can be realized. k1, k2, k6, k1
0 and k12 are substantially 0, and k3, k4, k5,
When k7, k8, k9 and k11 are substantially non-zero values, XC, 4L, 4R, XL and X in FIG.
A 5.0 channel surround system without a woofer speaker positioned at R can be realized. In the above-described embodiment, the localization direction of the lateral localization unit 12 is set to 90 degrees. Further, although the shuffler type filter is used as the lateral localization means 12, a lattice type filter may be used. When a lattice filter is used, the processing is complicated, but the speaker arrangement is
It is not necessary to limit to symmetric. In the above embodiment, the processing performed by the DSP 22 based on the program in the memory 26 has been described. However, the program performing the processing of the present invention may be recorded on various recording media according to the hardware configuration. For example, a signal processed by a program can be recorded on an audio recording medium (for example, CD, MD, DVD, CD-R) in the same manner as a normal acoustic signal. Further, for example, a signal processed by the program can be recorded as a video / audio file (for example, a wave file or an AC3 file) on a computer recording medium (for example, a CD-ROM, a DVD-ROM, or a floppy disk). Further, the program for performing the processing of the present invention can be applied not only as DSP firmware but also as encoding software. The present invention is applicable not only to video / sound reproduction devices,
It can be suitably applied to a game machine (for example, a pachinko machine, a so-called arcade game machine), an effector, game software, and the like.

According to the present invention, there is provided a sound image localization processing technique capable of obtaining an excellent surround effect with a simple configuration.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a hardware configuration when a DSP is used as a means for executing a program used in the present invention.

FIG. 2 shows processing contents according to a preferred embodiment of the present invention;
It is the figure represented by the signal flow.

FIG. 3 is a schematic diagram for explaining a state of sound image localization by the processing of FIG. 2;

FIG. 4 is a schematic diagram for explaining a state of sound image localization by the processing of FIG. 5;

FIG. 5 is a diagram illustrating a processing content according to another embodiment of the present invention in a signal flow.

FIG. 6 is a schematic diagram for explaining a state of sound image localization by the processing of FIG. 7;

FIG. 7 is a diagram illustrating processing contents according to still another embodiment of the present invention in a signal flow.

FIG. 8 is a diagram illustrating a process flow according to still another embodiment of the present invention by a signal flow.

FIG. 9 is a schematic diagram for explaining a conventional sound image localization processing device (lattice type).

FIG. 10 is a schematic diagram for explaining a conventional sound image localization processing device (shuffler type).

[Explanation of symbols]

 12 Side localization means 14L, 14R Delay means 16L, 16R Addition means

Claims (4)

[Claims] 1. A recording medium recording a sound image localization processing program, wherein the sound image localization processing program causes a computer to execute the following processing. Functioning a side localization means for outputting a signal for localization to the side of a listener to a right speaker and / or a left speaker; inputting a front left signal and a front right signal; By providing a delay means for outputting to the left speaker and the right speaker, respectively, after applying a delay equal to the delay time of the means, and further providing the side localization means with a front left signal and / or a front right signal, The left front signal and the right front signal are localized between the left and right speakers and the side of the listener. 2. A recording in which a sound image localization processing program is recorded.
Medium, wherein the sound image localization processing program executes the following processing:
Recording medium including causing a computer to execute the processing:
A difference signal generator that generates a difference signal between the front left signal and the front right signal.
Functioning the difference signal generated by the difference signal generating means.
Function as a filter means for outputting according to the transfer function Hs
With respect to the front left signal, the delay time of the filter means, etc.
Operating the first delay means for providing a new delay, for the front right signal, the delay time of the filter means, etc.
Functioning a second delay means for providing a new delay, an output of the first delay means and an output of the second delay means
Functioning the central mono signal generating means for adding the output of the filter means to the central mono signal.
To generate a signal to feed the left or right speaker
Functioning addition output means; and
The output of the filter means is subtracted from the
A subtraction output means for generating a signal to be given to the speaker.
Function, where the transfer function Hs is Hs = (h_{a '}-H_{b '}) /
(H_a-H_b) And h_{a '}Is the virtual speaker on the right
From the listener to the right ear of the listener, h_{b '} Is on the left
Transfer function from the virtual speaker to the right ear of the listener.
H_aIs the transfer function from the right speaker to the listener's right ear
And h_bFrom the left speaker to the listener's right ear
Is the transfer function. 3. A recording medium storing a sound image localization processing program, the recording medium including causing a computer to execute the following processing:
Functioning first addition means for adding a signal obtained by subjecting the front left signal to coefficient processing by the first coefficient and a signal obtained by subjecting the front right signal to coefficient processing by the first coefficient; A second adding means for adding a signal obtained by subjecting the front left signal to coefficient processing by the second coefficient and a signal obtained by subjecting the front right signal to coefficient processing by the second coefficient and inverting the phase thereof; A third adding means for adding a signal obtained by subjecting the surround left signal to coefficient processing by the third coefficient and a signal obtained by subjecting the surround right signal to coefficient processing by the third coefficient. A fourth signal for adding a signal obtained by subjecting the surround left signal to coefficient processing using the fourth coefficient and a signal obtained by performing coefficient processing using the fourth coefficient on the surround right signal and inverting the phase thereof; Function of addition of Causing the fifth addition means to add the output of the first addition means and the output of the third addition means to function; and providing the output of the second addition means and the fourth addition means Causing the sixth adding means for adding the output to function, to substantially reduce the transfer function H to the output of the fifth adding means.
_Causing the first filter means for performing a filtering process in accordance with _SUM to function; and applying substantially the transfer function H to the output of the sixth adding means.
Functioning a second filter means for _{performing a} filtering process in accordance with _DIF; and a first delay processing means for performing a delay process on a front left signal to compensate for a delay time caused by the first and second filter means. Functioning; functioning a second delay processing means for performing a delay processing on a front right signal to compensate for a delay time caused by the first and second filter means; A seventh adding means for adding a signal obtained by subjecting the output to the coefficient processing by the sixth coefficient and a signal obtained by applying the coefficient processing by the sixth coefficient to the output of the second delay processing means to function. A signal obtained by subjecting an output of the first delay processing means to a coefficient processing by a fifth coefficient, an output of a seventh adding means, and a seventh coefficient for an output of the first filtering means. Functioning an eighth adding means for adding a signal subjected to coefficient processing according to the above and a signal subjected to coefficient processing according to a seventh coefficient to an output of the second filter means, the second delay processing A signal obtained by subjecting the output of the means to coefficient processing by a fifth coefficient, an output of a seventh adding means, and a signal obtained by subjecting the output of the first filter means to coefficient processing by a seventh coefficient; Ninth adding means for performing a coefficient process using a seventh coefficient on the output of the second filter means and adding a signal whose phase has been inverted, and
And the output of the eighth adding means is an output for giving to the left speaker, and the output of the ninth adding means is an output for giving to the right speaker, wherein the transfer functions H _SUM and H _DIF H _SUM has the formula: _{= (h a '+ h b} ') / (h a + h b) H DIF = (h a '-h b') / (h a -h b) h a = h LL = H _RR , h _b = h _LR = h _RL , ha _'
= _{H L'L} = _{h R'R,} a _{h b '= h L'R =} h R'L, h LL is a transfer function from the left speaker to the left ear of the _{listener, h LR} is a left speaker H _RL is the transfer function from the right speaker to the listener's left ear, h _RR is the transfer function from the right speaker to the listener's right ear, h h _{L′ L} is a transfer function from the virtual left speaker to the listener's left ear, and h _{L′ R}
Is the transfer function from the virtual left speaker to right ear of the listener, h _R'L is a transfer function from the virtual right speaker to the left ear of the listener, and, h _R'R is received from the virtual right speaker This is the transfer function to the right ear of the listener. 4. CD, CD-R, CD-ROM, DV
4. The recording medium according to claim 1, wherein the recording medium is selected from D, a DVD-ROM, an MD, and a floppy disk.