Audio device, audio control method, and program

Abstract

To enable the formation of a high-quality sound image.SOLUTION: An audio device includes: a separation unit which separates, from a left input signal and a right input signal, independent components uncorrelated between a left channel and a right channel and corresponding to end sounds in which a sound image is localized at the left end or right end of a designated area, uncorrelated components uncorrelated between the left channel and right channel and corresponding to background sounds with a range of the sound image wider than the end sounds, and correlated components correlated between the left channel and right channel and corresponding to intermediate sounds in which the sound image is localized inside the localization position of the sound image of the right and left end sounds; and a sound image localization adjustment unit which adjusts at least one of the correlated components and independent components to localize the right and left sound images of the end sounds generated from the independent components at the right and left ends of the designated area, and localize the sound image of the intermediate sound generated from the correlated components between the localization positions of the right and left sound images of the end sounds.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] An embodiment of the present invention relates to an audio device, an audio control method, and a program. [Background technology]

[0002] In devices that output audio, a sound image localization technology is used that separates correlated components, which have correlation between channels, and uncorrelated components, which have no correlation between channels, from a two-channel stereo signal, and allows the user to perceive the position of a virtual sound source using these correlated and uncorrelated components. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2003-333698 A Summary of the Invention [Problem to be solved by the invention]

[0004] When attempting to achieve sound image localization using sound output from multiple built-in speakers on a display device such as a television, conventional sound image localization technology can result in multiple sound images that should be separated overlapping each other, resulting in degradation of the sound and a perceived lack of realism.

[0005] An object of the present invention is to provide an audio device, an audio control method, and a program that are capable of forming a high-quality sound image. [Means for solving the problem]

[0006] One embodiment of the present invention is an audio device that performs processing to output sound from a plurality of speakers, and includes a separation unit that separates, from a left input signal corresponding to a left channel and a right input signal corresponding to a right channel, an independent component corresponding to end sound that has no correlation between the left channel and the right channel and whose sound image is localized at the left or right end of a predetermined region, an uncorrelated component corresponding to background sound that has no correlation between the left channel and the right channel and whose sound image range is wider than the end sound, and a correlated component corresponding to intermediate sound that has a correlation between the left channel and the right channel and whose sound image is localized inside the localization positions of the sound images of the left and right end sounds; a sound image localization adjustment unit that adjusts at least one of the correlated component and the independent component so that the left and right sound images of the end sound generated from the independent component are localized at the left and right ends of the predetermined region, and the sound image of the intermediate sound generated from the correlated component is localized between the localization positions of the left and right sound images of the end sound; and an output control unit that outputs the end sound, the background sound, and the intermediate sound from the plurality of speakers. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram illustrating an example of a hardware configuration of a display device according to the first embodiment. [Diagram 2] FIG. 2 is a diagram showing an example of a configuration of a plurality of speakers according to the first embodiment. [Diagram 3] FIG. 3 is a diagram illustrating an example of a functional configuration of a DSP according to the first embodiment. [Figure 4] FIG. 4 is a diagram illustrating an example of the configuration of the separation unit according to the first embodiment. [Diagram 5] FIG. 5 is a diagram illustrating an example of components included in an input signal according to the first embodiment. [Figure 6] FIG. 6 is a diagram showing an example of a method for separating an independent component and an uncorrelated component from the difference between an Lch input signal and an Lch target signal according to the first embodiment. [Figure 7] FIG. 7 is a diagram showing an example of a method for separating an independent component and an uncorrelated component from the difference between the Rch input signal and the Rch target signal according to the first embodiment. [Figure 8]FIG. 8 is a diagram showing an example of the relationship between the output location of each sound and a sound image in the first embodiment. [Figure 9] FIG. 9 is a diagram showing an example of a sound image localization adjustment process for correlation components according to the first embodiment. [Figure 10] FIG. 10 is a flowchart showing an example of processing by the DSP according to the first embodiment. [Figure 11] FIG. 11 is a diagram showing an example of the configuration of a plurality of speakers of the display device 1 according to the second embodiment. [Figure 12] FIG. 12 is a diagram illustrating an example of a functional configuration of a DSP according to the second embodiment. [Figure 13] FIG. 13 is a diagram showing an example of the relationship between the output location of each sound and a sound image in the second embodiment. [Figure 14] FIG. 14 is a diagram showing an example of a sound image localization adjustment process for independent components and uncorrelated components according to the second embodiment. [Figure 15] FIG. 15 is a flowchart showing an example of processing by the DSP according to the second embodiment. [Figure 16] FIG. 16 is a diagram showing an example of the configuration of a plurality of speakers of the display device 1 according to the third embodiment. [Figure 17] FIG. 17 is a diagram illustrating an example of a functional configuration of a DSP according to the third embodiment. [Figure 18] FIG. 18 is a diagram illustrating an example of an input signal to the second separator according to the third embodiment. [Figure 19] FIG. 19 is a diagram showing an example of a method for separating an independent component from the difference between an Lch input signal and an Lch target signal according to the third embodiment. [Figure 20] FIG. 20 is a diagram showing an example of a method for separating an independent component from the difference between the Rch input signal and the Rch target signal according to the third embodiment. [Figure 21] FIG. 21 is a diagram showing an example of a sound image localization adjustment process for correlation components according to the third embodiment. [Figure 22] FIG. 22 is a diagram illustrating an example of components included in an input signal according to the third embodiment. [Figure 23] FIG. 23 is a diagram showing an example of a method for separating an independent component from the difference between an Lch input signal and an Lch target signal according to the third embodiment. [Figure 24] FIG. 24 is a diagram showing an example of a method for separating an independent component from the difference between the Rch input signal and the Rch target signal according to the third embodiment. [Diagram 25] FIG. 25 is a flowchart showing an example of processing by the DSP according to the third embodiment. [Figure 26] FIG. 26 is a diagram showing an example of the configuration of a plurality of speakers of the display device 1 according to the fourth embodiment. [Figure 27] FIG. 27 is a diagram illustrating an example of a functional configuration of a DSP according to the fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Below, exemplary embodiments of the present invention are disclosed.

[0009] (First embodiment) 1 is a diagram showing an example of a hardware configuration of a display device 1 according to a first embodiment. The display device 1 is a device capable of displaying video and outputting audio, and may be, for example, a television. The display device 1 illustrated here includes a processor 11, a memory 12, a UI (User Interface) 13, a peripheral circuit 14, a communication circuit 15, an audio decoder 16, an audio input ADC (Analog Digital Converter) 17, a DSP (Digital Signal Processor) 21 (an example of an audio device), an amplifier 22, and a speaker 23.

[0010] The processor 11 executes predetermined arithmetic processing and control processing according to a program stored in the memory 12. The memory 12 includes a main storage device such as a random access memory (RAM) or a read only memory (ROM) and an auxiliary storage device such as a solid state drive (SSD) or a hard disk drive (HDD), and stores programs and various data required to realize the functions of the display device 1. The UI 13 is a unit that accepts user operations. The peripheral circuit 14 is a circuit that assists the operation of the processor 11, and may be, for example, a power supply circuit, an oscillation circuit, a reset circuit, etc.

[0011] The communication circuit 15 is a circuit that acquires video signals, audio signals, etc. via an antenna, a communication network, etc. The audio decoder 16 is a device that decodes encrypted audio signals. The audio input ADC 17 is a device that converts analog audio signals into digital signals.

[0012] The DSP 21 is an information processing device that performs a predetermined process on an audio signal acquired from the communication circuit 15, the audio decoder 16, or the audio input ADC 17. The DSP 21 can be configured, for example, using a CPU (Central Processing Unit), a memory, an input / output port, and the like. The DSP 21 of this embodiment performs a process for optimizing the output of audio for each of the multiple speakers 23 built into the display device 1 so that the audio output from the multiple speakers 23 forms a predetermined sound image. The audio signal processed by the DSP 21 is output to each speaker 23 via the amplifier 22.

[0013] Fig. 2 is a diagram showing an example of the configuration of a plurality of speakers 23 according to the first embodiment. In Fig. 2, a state in which the display device 1 is viewed from the front side of the display 31 is illustrated.

[0014] As shown in FIG. 2, the display device 1 of this embodiment includes a left main speaker 23ML (an example of a first left speaker), a right main speaker 23MR (an example of a first right speaker), a left side speaker 23SL (an example of a second left speaker), and a right side speaker 23SR (an example of a second right speaker). The left main speaker 23ML is disposed near the left end of the lower part of the display device 1 (display 31). The right main speaker 23MR is disposed near the right end of the lower part of the display device 1. The left side speaker 23SL is disposed on the left side of the left main speaker 23ML on the left side of the display device 1. The right side speaker 23SR is disposed on the right side of the right main speaker 23MR on the right side of the display device 1.

[0015] The arrangement of the left main speaker 23ML, the right main speaker 23MR, the left side speaker 23SL, and the right side speaker 23SR is merely an example, and is not limited to the above.

[0016] 3 is a diagram showing an example of the functional configuration of the DSP 21 according to the first embodiment. The DSP 21 of this embodiment includes a separation unit 101, a sound image localization adjustment unit 102, and an output control unit 103. These functional units are configured by cooperation between hardware and software constituting the DSP 21. Furthermore, at least one of these functional units may be configured by dedicated hardware (circuits, etc.).

[0017] The separation unit 101 separates independent components, uncorrelated components, and correlated components from each of the Lch input signal and the Rch input signal, which are audio signals input to the DSP 21. The Lch input signal is a signal corresponding to the left channel in two-channel stereo reproduction of audio, and the Rch input signal is a signal corresponding to the right channel in the stereo reproduction.

[0018] An independent component is a component that has no correlation between the left and right channels and corresponds to an end sound whose sound image is localized at the left or right end of the display 31 (an example of a predetermined area). An uncorrelated component is a component that has no correlation between the left and right channels and corresponds to a background sound whose sound image range is wider than that of the end sound. A correlated component is a component that has a correlation between the left and right channels and corresponds to an intermediate sound whose sound image is localized inside the localization position of the sound image of the end sound.

[0019] The sound image localization adjustment unit 102 performs a sound image localization adjustment process for localizing the sound image of the sound output from the multiple speakers 23 (in this embodiment, the left main speaker 23ML, the right main speaker 23MR, the left side speaker 23SL, and the right main speaker 23MR) at an appropriate location. The sound image localization adjustment process of this embodiment includes a process of adjusting at least one of the correlated components and the independent components so that the left and right sound images of the end sound are localized at the left and right ends of the display 31 (display device 1) and the sound image of the intermediate sound is localized between the left and right localization positions of the sound image of the end sound.

[0020] The output control unit 103 outputs the end sound generated from the independent component, the background sound generated from the uncorrelated component, and the intermediate sound generated from the intermediate component from the corresponding speakers 23. In this embodiment, the Lch end sound generated from the independent component separated from the Lch input signal and the Lch background sound generated from the uncorrelated component separated from the Lch input signal are output from the left side speaker 23SL. The Rch end sound generated from the independent component separated from the Rch input signal and the Rch background sound generated from the uncorrelated component separated from the Rch input signal are output from the right side speaker 23SR. The Lch intermediate sound generated from the correlated component separated from the Lch input signal is output from the left main speaker 23ML. The Rch intermediate sound generated from the correlated component separated from the Rch input signal is output from the right main speaker 23MR.

[0021] 4 is a diagram illustrating an example of the configuration of the separation unit 101 according to the first embodiment. The separation unit 101 illustrated here includes adaptive filters 201L and 201R (examples of a filter unit) and adaptive algorithms 211L and 211R (examples of a coefficient update unit).

[0022] The adaptive filters 201L and 201R output output signals ol and or by applying a finite impulse response based on predetermined coefficients xl0 to xl7 and xr0 to xr7 to the left and right input signals il and ir, respectively. That is, the Lch adaptive filter 201L corresponding to the left channel outputs an output signal ol included in the Lch input signal by applying a finite impulse response based on coefficients xl0 to xl7 to the Lch input signal il. The Rch adaptive filter 201R corresponding to the right channel outputs an output signal or included in the Rch input signal by applying a finite impulse response based on coefficients xr0 to xr7 to the Rch input signal ir. Note that, although a case where the number of taps of the finite impulse response is 8 is illustrated here, the present invention is not limited to this.

[0023] The adaptive algorithms 211L and 211R are algorithms for optimizing the coefficients xl0 to xl7 and xr0 to xr7 of the adaptive filters 201L and 201R. The adaptive algorithms 211L and 211R update the coefficients xl(n) and xr(n) so that the error signal values ​​el(n) and er(n) based on the difference between the target signals tl and tr based on the difference between the Lch input signal il and the Rch input signal ir, and the output signals ol and or output from the adaptive filters 201L and 201R are minimized. In this example, n corresponds to the number of taps 8 of the adaptive filters 201L and 201R, and takes any value from 0 to 7. The Lch adaptive algorithm 211L corresponding to the left channel updates the coefficient xl(n) so as to minimize the error signal value el(n) which is the difference between the value obtained by multiplying a target signal tl, which is the difference (il-ir) between the Lch input signal il and the Rch input signal ir, by a predetermined weight gl, and the output signal ol output from the Lch adaptive filter 201L. The Rch adaptive algorithm 211R corresponding to the right channel updates the coefficient xr(n) so as to minimize the error signal value er(n) which is the difference between the value obtained by multiplying a target signal tr, which is the difference (ir-il) between the Rch input signal ir and the Lch input signal il, by a predetermined weight gr, and the output signal or output from the Rch adaptive filter 201R.

[0024] The adaptive filters 201L, 201R, whose coefficients xl0-xl7, xr0-xr7 are optimized by the above-mentioned adaptive algorithms 211L, 211R, separate the independent components and uncorrelated components corresponding to the error signals el(n), er(n) from the input signals il, ir. Then, the independent components and uncorrelated components are subtracted from the input signals to separate the correlated components. Furthermore, the above-mentioned configuration makes it unnecessary for the adaptive filters 201L, 201R to filter (erase) the uncorrelated components, reduces abrupt changes in the frequency characteristics of the filters, and suppresses the generation of components that cause abnormal noise.

[0025] 5 is a diagram showing an example of components included in the input signals il and ir according to the first embodiment. In this example, the Lch input signal il includes an uncorrelated component UL, an independent component IL, and correlated components CC, CL1, CL2, CR1, and CR2, and the Rch input signal ir includes an uncorrelated component UR, an independent component IR, and correlated components CC, CL1, CL2, CR1, and CR2.

[0026] The uncorrelated component UL included in the Lch input signal il is a component that is not correlated with the Rch input signal ir and corresponds to background sound. The uncorrelated component UR included in the Rch input signal ir is a component that is not correlated with the Lch input signal il and corresponds to background sound. The background sound is, for example, a sound whose sound image is localized so as to spread across the entire left and right areas of the display 31.

[0027] The independent component IL included in the Lch input signal il is a component that is not correlated with the Rch input signal ir and corresponds to the left end sound. The independent component IR included in the Rch input signal ir is a component that is not correlated with the Lch input signal il and corresponds to the right end sound. The end sound is, for example, a sound whose sound image is localized at the left or right end of the display 31 or near the end. For example, the sound image of the left end sound is localized at the left end of the display 31, and the sound image of the right end sound is localized at the right end of the display 31. In FIG. 5, the weight 1.0, which is the value accumulated on the independent components IL and IR, indicates the difference in sound output level (volume) between the left and right channels. That is, it is shown that the left end sound corresponding to the independent component IL is output entirely from the left channel side and not output from the right channel side, and the right end sound corresponding to the independent component IR is output entirely from the right channel side and not output from the left channel side.

[0028] The correlation components CC, CL1, CL2, CR1, and CR2 are correlated between the Rch input signal ir and the Lch input signal il, and are components corresponding to intermediate sound. The intermediate sound is, for example, a sound whose sound image is localized inside the localization positions of the left and right sound images of the end sound. The correlation component CC is a component corresponding to a sound whose sound image is localized at the center position in the left and right sound image range of the intermediate sound. The correlation component CL1 is a component corresponding to a sound whose sound image is localized at a position to the left of the center position in the sound image range. The correlation component CL2 is a component corresponding to a sound whose sound image is localized at a position to the left of the localization position of the sound of the correlation component CL1 and to the right of the localization position of the left sound image of the end sound in the sound image range. The correlation component CR1 is a component corresponding to a sound whose sound image is localized at a position to the right of the center position in the sound image range. The correlated component CR2 is a component corresponding to a sound whose sound image is localized to the right of the localization position of the sound of the correlated component CR1 and to the left of the localization position of the sound image on the right side of the end sound in the sound image range.

[0029] In Fig. 5, the weights (0.90, 0.80, 0.70, 0.60, 0.44 in this example) which are values ​​accumulated in the correlation components CC, CL1, CL2, CR1, and CR2 respectively, indicate the difference in audio output level between the left and right channels. In other words, it is shown that the output level from the left channel of the intermediate audio corresponding to the correlation components CL1 and CL2 is greater than the output level from the right channel. It is also shown that the output level difference between the left and right channels in the correlation component CL2 is greater than the output level difference between the left and right channels in the correlation component CL1. The same is true for the correlation components CR1 and CR2. Note that the weights exemplified here are, when the weight in the left channel is Wl and the weight in the right channel is Wr, Wl 2 +Wr 2 is set to be 1 or approximately 1. For example, the left and right weights of the correlation component CL1 are set to 0.90 2 +0.44 2 ≒1.0, and the left and right weights of the correlation component CL2 are 0.80 2 +0.64 2 = 1.0. The same is true for the correlation components CR1 and CR2.

[0030] Based on the difference between the above-mentioned input signals il, ir and the target signals tl, tr, the independent components IL, IR and the uncorrelated components UL, UR can be separated.

[0031] 6 is a diagram showing an example of a method for separating an independent component IR and an uncorrelated component UR from the difference between an Lch input signal il and an Lch target signal tl according to the first embodiment. As described above, the Lch target signal tl is a signal obtained by subtracting the Rch input signal ir from the Lch input signal il. As shown in FIG. 6, since both the Lch input signal il and the Lch target signal tl contain the Lch independent component IL, the Lch uncorrelated component UL, and the correlated components CL1, CL2, CR1, and CR2, the Rch independent component IR and the Rch uncorrelated component UR contained in the Rch input signal ir can be separated by taking the difference between the Lch input signal il and the Lch target signal tl.

[0032] 7 is a diagram showing an example of a method for separating an independent component IL and an uncorrelated component UL from the difference between an Rch input signal ir and an Rch target signal tr according to the first embodiment. As described above, the Rch target signal tr is a signal obtained by subtracting an Lch input signal il from an Rch input signal ir. As shown in FIG. 7, since both the Rch input signal ir and the Rch target signal tr contain an Rch independent component IR, an Rch uncorrelated component UR, and correlated components CL1, CL2, CR1, and CR2, the Lch independent component IL and the Lch uncorrelated component UL contained in the Lch input signal il can be separated by taking the difference between the Rch input signal ir and the Rch target signal tr.

[0033] Then, by taking the difference between the Lch independent component IL and the Lch uncorrelated component UL separated as described above and the Lch input signal il, the Lch correlated components CC, CL1, CL2, CR1, and CR2 corresponding to the left channel can be separated. Also, by taking the difference between the Rch independent component IR and the Rch uncorrelated component UR separated as described above and the Rch input signal ir, the Rch correlated components CC, CL1, CL2, CR1, and CR2 corresponding to the right channel can be separated.

[0034] Fig. 8 is a diagram showing an example of the relationship between the output location of each sound and the sound image in the first embodiment. In Fig. 8, sound image LL indicates the sound image on the left side of the end sound, and sound image RR indicates the sound image on the right side of the end sound. Sound image UU indicates the sound image of the background sound. Sound images C, L1, L2, R1, and R2 indicate the sound images of the middle sound.

[0035] The output control unit 103 of this embodiment outputs the Lch end sound generated from the Lch independent component IL from the left side speaker 23SL, and outputs the Rch end sound generated from the Rch independent component IR from the right side speaker 23SR. This allows the left sound image LL of the end sound to be localized at the installation position of the left side speaker 23SL, and the right sound image RR of the end sound to be localized at the installation position of the right side speaker 23SR.

[0036] In addition, the output control unit 103 outputs the Lch background sound generated from the Lch uncorrelated component UL from the left side speaker 23SL, and outputs the Rch background sound generated from the Rch uncorrelated component UR from the right side speaker 23SR. This allows the sound image UU of the background sound to be localized so as to spread in the space between the installation positions of the left side speaker 23SL and the right side speaker 23SR.

[0037] Furthermore, the output control unit 103 outputs the Lch intermediate sound generated from the Lch correlation components CC, CL1, CL2, CR1, and CR2 from the left main speaker 23ML, and outputs the Rch intermediate sound generated from the Rch correlation components CC, CL1, CL2, CR1, and CR2 from the right main speaker 23MR. This allows the sound images C, L1, L2, R1, and R2 of the intermediate sounds to be localized between the localization positions of the sound images LL and RR of the left and right end sounds.

[0038] At this time, the sound image localization adjustment unit 102 of this embodiment adjusts the left and right weights of the correlation components CC, CL1, CL2, CR1, and CR2 so that the leftmost sound image L2 of the intermediate sound is localized at the installation position of the left main speaker 23ML, and the rightmost sound image R2 is localized at the installation position of the right main speaker 23MR.

[0039] Fig. 9 is a diagram showing an example of sound image localization adjustment processing for correlation components CC, CL1, CL2, CR1, and CR2 according to the first embodiment. In Fig. 9, the upper part shows an example of a state before adjustment, and the lower part shows an example of a state after adjustment. In the pre-adjustment state, since the weight of the right channel of the left end correlation component CL2 is a value greater than 0 (0.44 in this example), the left end sound image L2 of the intermediate sound is localized inside the installation position of the left main speaker 23ML. Similarly, since the weight of the left channel of the right end correlation component CR2 is a value greater than 0 (0.44 in this example), the right end sound image R2 of the intermediate sound is localized inside the installation position of the right main speaker 23MR.

[0040] 9, the left end sound image L2 of the intermediate sound can be localized at the installation position of the left main speaker 23ML by setting the right channel weight of the left end correlation component CL2, i.e., the output level from the right main speaker 23MR, to 0 and adjusting the other weights as appropriate. Similarly, the right end sound image R2 of the intermediate sound can be localized at the installation position of the right main speaker 23MR by setting the left channel weight of the right end correlation component CR2, i.e., the output level from the left main speaker 23ML, to 0 and adjusting the other weights as appropriate.

[0041] 10 is a flowchart showing an example of processing by the DSP 21 according to the first embodiment. In step S101, the separation unit 101 separates the independent components IL and IR, the uncorrelated components UL and UR, and the correlated components CC, CL1, CL2, CR1, and CR2 from the input signals il and ir. That is, the separation unit 101 separates the Lch independent component IL, the Lch uncorrelated component UL, and the Lch correlated components CC, CL1, CL2, CR1, and CR2 from the Lch input signal il, and the separation unit 101 separates the Rch independent component IR, the Rch uncorrelated component UR, and the Rch correlated components CC, CL1, CL2, CR1, and CR2 from the Rch input signal ir.

[0042] In step S102, the sound image localization adjustment unit 102 performs a sound image localization adjustment process on the independent components and the correlated components so that the left and right sound images LL and RR of the end sound are localized at the installation positions of the left and right side speakers 23SL and 23R (one example of the left and right ends of the display device 1), respectively, and the sound images C, L1, L2, R1, and R2 of the middle sound are localized between the localization positions of the left and right sound images LL and RR of the end sound. At this time, for example, the Lch independent component IL is adjusted so that the output level of the R channel is 0, and the Rch independent component IR is adjusted so that the output level of the LR channel is 0. In addition, the correlated components CC, CL1, CL2, CR1, and CR2 are adjusted so that the output level of the R channel of the leftmost component is 0 and the output level of the L channel of the rightmost component is 0, as illustrated in FIG. 9, for example.

[0043] In step S103, the output control unit 103 outputs the end sound generated from the independent components and the background sound generated from the uncorrelated components from the side speakers 23SL and 23SR. As a result, the left sound image LL of the end sound is localized at the installation position of the left side speaker 23SL, and the right sound image RR of the end sound is localized at the installation position of the right side speaker 23SR. In addition, the sound image UU of the background sound is localized so as to spread in the space between the installation positions of the left side speaker 23SL and the right side speaker 23SR.

[0044] In addition, in step S104, the output control unit 103 outputs the intermediate sound generated from the correlation components from the main speakers 23ML and 23MR. As a result, the sound images C, L1, L2, R1, and R2 of the intermediate sound are localized between the left and right sound images LL and RR of the end sound. Note that steps S103 and S104 are actually executed in parallel.

[0045] As described above, according to this embodiment, the input signal is separated into independent components, uncorrelated components, and correlated components, and the intermediate sound generated from the correlated components is output from the main speakers 23ML and 23MR, and the end sound generated from the independent components is output from the side speakers 23SL and 23R arranged outside the main speakers 23ML and 23MR. This allows the sound images LL and RR of the end sound to be localized at the end of the display 31, and it is possible to secure a wide area for localizing the sound images C, L1, L2, R1, and R2 of the intermediate sound. This makes it possible to suppress deterioration of the sound and reduction in the sense of realism caused by the sound images C, L1, L2, R1, and R2 of the intermediate sound and the sound images LL and RR of the end sound overlapping each other. In addition, by outputting the background sound generated from the uncorrelated components from the side speakers 23SL and 23SR, it is possible to localize the sound image UU of the background sound so that it spreads across the entire left and right area of ​​the display 31. This makes it possible to form a high-quality sound image and output high-quality audio with a high sense of realism.

[0046] Other embodiments will be described below with reference to the drawings, but descriptions of parts that are the same as or similar to the first embodiment will be omitted as appropriate.

[0047] Second embodiment 11 is a diagram showing an example of the configuration of the multiple speakers 23 of the display device 1 according to the second embodiment. In this embodiment, the side speakers 23SL and 23SM in the first embodiment do not exist. That is, in this embodiment, the end sound, background sound, and middle sound are all output from the main speakers 23ML and 23MR.

[0048] Fig. 12 is a diagram showing an example of the functional configuration of the DSP 21 according to the second embodiment. Fig. 13 is a diagram showing an example of the relationship between the output location of each sound and a sound image in the second embodiment.

[0049] As shown in FIG. 12, the output control unit 103 of this embodiment outputs the Lch end sound, the Lch background sound, and the Lch intermediate sound to the left main speaker 23ML, and outputs the Rch end sound, the Rch background sound, and the Rch intermediate sound to the right main speaker 23MR.

[0050] The sound image localization adjustment unit 102 of this embodiment adjusts the independent components so that the left sound image LL of the end sound is localized to the left of the installation position of the left main speaker 23ML, and the right sound image RR of the end sound is localized to the right of the installation position of the right main speaker 23MR, as shown in Fig. 13. The sound image localization adjustment unit 102 of this embodiment adjusts the uncorrelated components so that the left end of the sound image UU of the background sound reaches to the left of the installation position of the left main speaker 23ML, and the right end of the sound image UU reaches to the right of the installation position of the right main speaker 23MR. The sound image localization adjustment unit 102 of this embodiment adjusts the correlated components so that the left end sound image L2 of the middle sound is localized to the installation position of the left main speaker 23ML, and the right end sound image R2 of the middle sound is localized to the installation position of the right main speaker 23MR.

[0051] 14 is a diagram showing an example of a sound image localization adjustment process for the independent components IL, IR and the uncorrelated components UL, UR according to the second embodiment. The sound image localization adjustment unit 102 of this embodiment adjusts the independent components IL, IR and the uncorrelated components UL, UR by utilizing crosstalk canceling.

[0052] In FIG. 14, the components indicated by the dashed lines correspond to the correction components for realizing crosstalk canceling. That is, as the Lch components, a correction component -0.96*IR' having an opposite phase to the independent component 1.96*IR of the Rch and a correction component -0.96*UR' having an opposite phase to the uncorrelated component 1.96*UR of the Rch are added. Also, as the Rch components, a correction component -0.96*IL' having an opposite phase to the independent component 1.96*IL of the Lch and a correction component -0.96*UL' having an opposite phase to the uncorrelated component 1.96*UL of the Lch are added. Such correction components can be generated, for example, by using a known crosstalk canceling circuit or the like. By using such correction components, the left sound image LL of the end sound can be shifted to the left from the installation position of the left main speaker 23ML, and the right sound image RR of the end sound can be shifted to the right from the installation position of the right main speaker 23MR. Also, the sound image UU of the background sound can be expanded so that its left end reaches to the left of the installation position of the left main speaker 23ML and its right end reaches to the right of the installation position of the right main speaker 23MR.

[0053] 15 is a flowchart showing an example of processing by the DSP 21 according to the second embodiment. In step S201, the separation unit 101 separates independent components IL, IR, uncorrelated components UL, UR, and correlated components CC, CL1, CL2, CR1, and CR2 from the input signals il, ir.

[0054] In step S202, the sound image localization adjustment unit 102 performs a sound field localization tonality process to adjust independent components so that the left sound image LL of the end sound is localized to the left of the installation position of the left main speaker 23ML, and the right sound image RR of the end sound is localized to the right of the installation position of the right main speaker 23MR. The sound image localization adjustment unit 102 also performs a sound field localization adjustment process to adjust uncorrelated components so that the left end of the sound image UU of the background sound reaches the left side of the installation position of the left main speaker 23ML, and the right end of the sound image UU reaches the right side of the installation position of the right main speaker 23MR. The sound image localization adjustment unit 102 also performs a sound field localization adjustment process to adjust correlated components so that the left end sound image L2 of the middle sound is localized to the installation position of the left main speaker 23ML, and the right end sound image R2 of the middle sound is localized to the installation position of the right main speaker 23MR.

[0055] In step S203, the output control unit 103 outputs the end sound generated from the independent components, the background sound generated from the uncorrelated components, and the intermediate sound generated from the correlated components from the main speakers 23ML and 23MR. As a result, the left and right sound images LL and RR of the end sound are localized at positions outside the left and right main speakers 23ML and 23MR, respectively, and the sound images C, L1, L2, R1, and R2 of the intermediate sound are localized between the left and right sound images LL and RR of the end sound. In addition, the sound image UU of the background sound is localized so that its left end reaches to the left of the installation position of the left main speaker 23ML and its right end reaches to the right of the installation position of the right main speaker 23MR.

[0056] As described above, according to this embodiment, the sound images LL and RR of the end sound generated from the independent components can be localized near the left and right ends of the display 31 without using the side speakers 23SL and 23SM, and a wide area can be secured for localizing the sound images C, L1, L2, R1, and R2 of the intermediate sound. In addition, the sound image UU of the background sound can be localized so as to spread across the entire left and right areas of the display 31. This makes it possible to form a high-quality sound image using two speakers, and to output high-quality sound with a high sense of realism while suppressing increases in costs.

[0057] Third embodiment 16 is a diagram showing an example of the configuration of a plurality of speakers 30 of a display device 1 according to a third embodiment. In this embodiment, an example is shown in which three center speakers are added to the speakers in the first embodiment. The display device 1 of this embodiment includes a left main speaker 30ML (an example of a first left speaker), a right main speaker 30MR (an example of a first right speaker), a left side speaker 30SL (an example of a second left speaker), and a right side speaker 30SR (an example of a second right speaker), as well as a left center speaker 30SCL (an example of a third left speaker), a right center speaker 30SCR (an example of a third right speaker), and a center speaker 30SC.

[0058] The left main speaker 30ML is disposed near the left end of the lower part of the display 31. The right main speaker 30MR is disposed near the right end of the lower part of the display 31. The left side speaker 30SL is disposed on the left side of the display 31, at a position above and to the left of the left main speaker 30ML. The right side speaker 30SR is disposed on the right side of the display 31, at a position above and to the right of the right main speaker 30MR. Furthermore, the center speaker 30SC is disposed below the center of the display 31. The left center speaker 30SCL is disposed between the center speaker 30SC and the left main speaker 30ML. The right center speaker 30SCR is disposed between the center speaker 30SC and the right main speaker 30MR.

[0059] The sound images LL and RR are end sounds output from the left side speaker 30SL and the right side speaker 30SR and localized at the positions of the left side speaker 30SL and the right side speaker 30SR. The sound images L2 and R2 are left and right main sounds output from the left main speaker 30ML and the right main speaker 30MR and localized at the positions of the left main speaker 30ML and the right main speaker 30MR. The sound images L1 and R1 are left and right center sounds output from the left center speaker 30SCL and the right center speaker 30SCR and localized at the positions of the left center speaker 30SCL and the right center speaker 30SCR. The sound image C is a center sound output from the center speaker 30SC and localized at the position of the center speaker 30SC.

[0060] Therefore, independent components of sound are output from each speaker. Note that the above arrangement of the speakers is an example, and is not limited to the above. That is, the speaker may be arranged at the top instead of the bottom. Furthermore, although an example is given in which an end sound, a background sound, and a middle sound are respectively assigned to each speaker, the number of speakers is not limited.

[0061] 17 is a diagram showing an example of the functional configuration of the DSP 21 according to the third embodiment. The DSP 21 of the third embodiment includes separation sections 301-303, sound image localization adjustment sections 311-312, and output control sections 321-327.

[0062] The separation unit includes a first separation unit 301, a second separation unit 302, and a third separation unit 303. The first separation unit 301 separates each of an Lch input signal and an Rch input signal, which are audio signals input to the DSP 21, into an independent component, an uncorrelated component, and a correlated component. The input signal is also called an input audio signal. Then, the first separation unit 301 sends the independent component and the uncorrelated component to an output control unit 321 and an output control unit 322. Furthermore, the first separation unit 301 sends the correlated component to a first sound image localization adjustment unit 311. The Lch input signal is a signal corresponding to the left channel in two-channel stereo reproduction of audio, and the Rch input signal is a signal corresponding to the right channel in the stereo reproduction. The uncorrelated component indicates, for example, that the correlation between the audio signal output on the left channel and the audio signal output on the right channel is less than a predetermined value. The correlated component indicates, for example, that the correlation between the left channel and the right channel is greater than a predetermined value.

[0063] The second separation unit 302 separates each of the Lch input signal and the Rch input signal, which are audio signals input from the first sound image localization adjustment unit 311, into a second correlated component and a second independent component. Then, the second independent component is sent to the output control units 323 and 324. Furthermore, the second correlated component is sent to the second sound image localization adjustment unit 312. Similarly, the third separation unit 303 separates each of the Lch input signal and the Rch input signal, which are audio signals input from the second sound image localization adjustment unit 312, into a third correlated component and a third independent component. Then, the third independent component is sent to the output control units 325 and 326. Furthermore, the third correlated component is sent to the output control unit 327. Note that, although the third separation unit 303 has been described as an example, a plurality of further separation units may be provided.

[0064] The sound image localization adjustment unit includes a first sound image localization adjustment unit 311 and a second sound image localization adjustment unit 312. The first sound image localization adjustment unit 311 adjusts the weights of the left and right channels so as to derive a second independent component from the correlated component input from the first separation unit 301. This allows weight adjustment from the correlated component to the second independent component and the second correlated component, and makes it possible to derive the second independent component that localizes the sound image at the position of the speakers. That is, the correlated component is adjusted to the second independent component and the second correlated component so that the sound image is localized at the positions of the left main speaker 30ML and the right main speaker 30MR.

[0065] The second sound image localization adjustment unit 312 performs the same process as the first sound image localization adjustment unit 311. The weights of the left and right channels are adjusted so as to derive a third independent component from the second correlated component of the second separation unit 302. This allows weight adjustment from the second correlated component to the third independent component and the third correlated component, and makes it possible to derive the third independent component that localizes the sound image at the position of the speakers. That is, the second correlated component is adjusted to the third independent component and the third correlated component so that the sound image is localized at the positions of the left center speaker 30SCL and the right center speaker 30SCR.

[0066] Each speaker is assigned to the output control units 321 to 327. For example, the output control unit 321 is assigned to the left side speaker 30SL and controls to output the Lch end sound and the Lch background sound. The output control unit 322 is assigned to the right side speaker 30SR and controls to output the Rch end sound and the Rch background sound. In addition, the uncorrelated components and the independent components are input from the first separation unit 301 to the output control units 321 to 322.

[0067] The output control unit 323 is assigned to the left main speaker 30ML and controls to output the Lch main sound. The output control unit 324 is assigned to the right main speaker 30MR and controls to output the Rch main sound. The output control unit 323 and the output control unit 324 also receive the second independent component from the second separation unit 302.

[0068] The output control unit 325 is assigned to the left center speaker 30SCL and controls to output the Lch center audio. The output control unit 326 is assigned to the left center speaker 30SCR and controls to output the Rch center audio. The output control unit 325 and the output control unit 326 also receive the third independent component from the third separation unit 303. The output control unit 327 is assigned to the center speaker 30SC and controls to output the center audio. The output control unit 327 also receives the third correlated component from the third separation unit 303. Other configurations may be the same as those in the first embodiment.

[0069] In the third embodiment, an input signal input to first separation section 301 is shown in, for example, FIG. 5. A method for separating uncorrelated components and independent components by first separation section 301 is shown in, for example, FIG. 6 and FIG. 7. Next, an adjustment process by first sound image localization adjustment section 311 is shown in, for example, FIG. 9. The adjusted signal shown in FIG. 9 is output to second separation section 302.

[0070] 18 is a diagram showing an example of an input signal to the second separating section 302 according to the third embodiment. In the third embodiment, the Lch input signal il includes a second independent component CL2 and second correlated components CC, CL1, and CR1, and the Rch input signal ir includes a second independent component CR2 and second correlated components CC, CL1, and CR1.

[0071] The second independent component CL2 included in the Lch input signal il is a component that is uncorrelated with the Rch input signal ir and corresponds to the left Lch main sound. The second independent component CR2 included in the Rch input signal ir is a component that is uncorrelated with the Lch input signal il and corresponds to the right Rch main sound.

[0072] The main sound is, for example, a sound whose sound image is localized inside an end sound whose sound image is localized at or near the left or right end of the display 31. For example, the sound image of the Lch main sound on the left side is localized at the position of the left main speaker 30ML. The sound image of the Rch main sound on the right side is localized at the position of the right main speaker 30MR.

[0073] 18, the weight 1.34, which is the value accumulated in the second independent components CL2 and CR2, indicates the difference in sound output level (volume) between the left and right channels. That is, it is shown that the Lch main sound on the left side corresponding to the second independent component CL2 is entirely output from the left channel side and not output from the right channel side, and the Rch main sound on the right side corresponding to the second independent component CR2 is entirely output from the right channel side and not output from the left channel side.

[0074] The second correlation components CC, CL1, and CR1 are correlated between the Rch input signal ir and the Lch input signal il, and correspond to the center sound. The weights (0.99, 0.70, and 0.41 in this example) that are multiplied by the second correlation components CC, CL1, and CR1 respectively indicate the output level difference of the sound between the left and right channels.

[0075] That is, it is shown that the output level from the left channel of the Lch center sound corresponding to the second correlation component CL1 is higher than the output level from the right channel, and the output level from the right channel of the Rch center sound corresponding to the second correlation component CR1 is higher than the output level from the left channel.

[0076] Based on the difference between the above-mentioned input signals il, ir and the target signals tl, tr, the second independent components CL2, CR2 can be separated.

[0077] 19 is a diagram showing an example of a method for separating the second independent component CR2 from the difference between the Lch input signal il and the Lch target signal tl to the second separation unit 302 according to the third embodiment. As described above, the Lch target signal tl is a signal obtained by subtracting the Rch input signal ir from the Lch input signal il. As shown in FIG. 19, since both the Lch input signal il and the Lch target signal tl contain the Lch second independent component CL2 and the second correlation components CL1 and CR1, the Rch second independent component CR2 contained in the Rch input signal ir can be separated by taking the difference between the Lch input signal il and the Lch target signal tl. The Rch second independent component CR2 is sent to the output control unit 324.

[0078] 20 is a diagram showing an example of a method for separating the second independent component CL2 from the difference between the Rch input signal ir and the Rch target signal tr to the second separation unit 302 according to the third embodiment. As described above, the Rch target signal tr is a signal obtained by subtracting the Lch input signal il from the Rch input signal ir. As shown in FIG. 20, since the Rch second independent component CR2 and the second correlation components CL1 and CR1 are included in both the Rch input signal ir and the Rch target signal tr, the Lch second independent component CL2 included in the Lch input signal il can be separated by taking the difference between the Rch input signal ir and the Rch target signal tr. The Lch second independent component CL2 is sent to the output control unit 323.

[0079] As described above, the second separator 302 can separate the Lch second correlated components CC, CL1, and CR1 corresponding to the left channel by taking the difference between the Lch second independent component CL2 and the Lch input signal il. Also, the second separator 302 can separate the Rch second correlated components CC, CL1, and CR1 corresponding to the right channel by taking the difference between the Rch second independent component CR2 separated as described above and the Rch input signal ir.

[0080] Fig. 21 is a diagram showing an example of a sound image localization adjustment process for the second correlation components CC, CL1, and CR1 according to the third embodiment by the second sound image localization adjustment unit 312. In Fig. 21, the upper part of Fig. 21 illustrates a state before adjustment, and the lower part of Fig. 21 illustrates a state after adjustment.

[0081] The sound image L1 of the Lch center sound is adjusted so as to be localized at the installation position of the left center speaker 30SCL. In the state before adjustment shown in the upper part of Fig. 21, the weight of the right channel of the second correlation component CL1 on the left side is a value greater than 0 (0.41 in this example), so the sound image L1 of the Lch center sound is localized inside the installation position of the left center speaker 30SCL.

[0082] Similarly, it is desired that the sound image R1 of the Rch center sound be localized at the installation position of the right center speaker 30SCR. In the pre-adjustment state shown in the upper part of Fig. 21, the weight of the left channel of the second correlation component CR1 on the right side is a value greater than 0 (0.41 in this example), so the sound image R1 of the Rch center sound is localized inward from the installation position of the right center speaker 30SCR.

[0083] Therefore, as shown in the post-adjustment state in the lower part of Fig. 21, the weight of the right channel of the second correlation component CL1 on the left side, i.e., the output level of the right center speaker 30SCR, is set to 0, and other weights are adjusted appropriately. This allows the sound image L1 of the Lch center sound to be localized at the installation position of the left center speaker 30SCL.

[0084] Similarly, the weight of the left channel of the second correlation component CR1 on the right side, i.e., the output level of the left center speaker 30SCL, is set to 0, and the other weights are adjusted appropriately. This allows the sound image R1 of the Rch center sound to be localized at the installation position of the right center speaker 30SCR.

[0085] 22 is a diagram showing an example of an input signal to the third separator 303 according to the third embodiment. In the third embodiment, the Lch input signal il includes a third independent component CL1 and a third correlated component CC, and the Rch input signal ir includes a third independent component CR1 and a third correlated component CC.

[0086] The third independent component CL1 included in the Lch input signal il is a component that is uncorrelated with the Rch input signal ir and corresponds to the Lch center sound on the left side. The third independent component CR1 included in the Rch input signal ir is a component that is uncorrelated with the Lch input signal il and corresponds to the Rch center sound on the right side.

[0087] The center sound is, for example, a sound whose sound image is localized more inward than the main sound whose sound image is localized more inward than the left and right ends of the display 31. For example, the sound image of the Lch center sound on the left side is localized at the position of the left center speaker 30SCL. The sound image of the Rch center sound on the right side is localized at the position of the right center speaker 30SCR.

[0088] As shown in Fig. 22, the weight 1.40, which is the value accumulated in the third independent components CL1 and CR1, indicates the difference in audio output level (volume) between the left and right channels. That is, it is shown that the left Lch center audio corresponding to the third independent component CL1 is output entirely from the left channel side and not output from the right channel side, and the right Rch center audio corresponding to the third independent component CR1 is output entirely from the right channel side and not output from the left channel side.

[0089] The third correlation component CC is a component that is correlated between the Rch input signal ir and the Lch input signal il and corresponds to the center sound. The weight (0.70 in this example) that is the value integrated into the third correlation component CC indicates the difference in sound output level between the left and right channels.

[0090] Based on the difference between the above-mentioned input signals il, ir and the target signals tl, tr, the third independent components CL1, CR1 can be separated.

[0091] 23 is a diagram showing an example of a method for separating the third independent component CR1 from the difference between the Lch input signal il and the Lch target signal tl to the third separation section 303 according to the third embodiment. As described above, the Lch target signal tl is a signal obtained by subtracting the Rch input signal ir from the Lch input signal il. As shown in FIG. 23, since the Lch third independent component CL1 is included in both the Lch input signal il and the Lch target signal tl, the Rch third independent component CR1 included in the Rch input signal ir can be separated by taking the difference between the Lch input signal il and the Lch target signal tl. The Rch third independent component CR1 is sent to the output control section 326.

[0092] 24 is a diagram showing an example of a method for separating the third independent component CL1 from the difference between the Rch input signal ir and the Rch target signal tr to the third separation unit 303 according to the third embodiment. As described above, the Rch target signal tr is a signal obtained by subtracting the Lch input signal il from the Rch input signal ir. As shown in FIG. 24, since the Rch third independent component CR1 is included in both the Rch input signal ir and the Rch target signal tr, the Lch third independent component CL1 included in the Lch input signal il can be separated by taking the difference between the Rch input signal ir and the Rch target signal tr. The Lch third independent component CL1 is sent to the output control unit 325.

[0093] As described above, the third separation unit 303 can separate the Lch third correlated component CC corresponding to the left channel by taking the difference between the Lch third independent component CL1 and the Lch input signal il. Also, the third separation unit 303 can separate the Rch third correlated component CC corresponding to the right channel by taking the difference between the Rch third independent component CR1 separated as described above and the Rch input signal ir.

[0094] Then, one of the left and right channel signals of the third correlated component CC is sent to the output control unit 327. Alternatively, the left and right channel signals are added and multiplied by 0.5 to produce the third correlated component CC, which is sent to the output control unit 327. Thus, the center sound generated from the third correlated component CC is output from the center speaker 30SC. As a result, the sound image C of the center sound is localized at the position of the center speaker 30SC.

[0095] Next, Fig. 25 is a flowchart showing an example of processing by the DSP 21 according to the third embodiment. In step S301, the first separator 301 separates the independent components IL and IR, the uncorrelated components UL and UR, and the correlated components CC, CL1, CL2, CR1, and CR2 from the input signals il and ir. That is, the Lch independent component IL, the Lch uncorrelated component UL, and the Lch correlated components CC, CL1, CL2, CR1, and CR2 are separated from the Lch input signal il, and the Rch independent component IR, the Rch uncorrelated component UR, and the Rch correlated components CC, CL1, CL2, CR1, and CR2 are separated from the Rch input signal ir (step S301).

[0096] In step S302, the first sound image localization adjustment unit 311 performs a sound field localization adjustment process to further generate a second independent component from the Lch and Rch correlated components CC, CL1, CL2, CR1, and CR2. Specifically, the Lch correlated component CL2 is adjusted so that the output level of the R channel becomes 0, resulting in the Lch second independent component CL2. Similarly, the Rch correlated component CR2 is adjusted so that the output level of the L channel becomes 0, resulting in the Rch second independent component CR2 (step S302).

[0097] In step S303, the second separation unit 302 separates the second independent components CL2, CR2 and the second correlated components CC, CL1, CR1 from the Lch and Rch input signals il, ir from the first sound image localization adjustment unit. That is, the Lch second independent component CL2 and the Lch second correlated components CC, CL1, CR1 are separated from the Lch input signal il, and the Rch second independent component CR2 and the Rch second correlated components CC, CL1, CR1 are separated from the Rch input signal ir (step S303).

[0098] In step S304, the second sound image localization adjustment unit 312 performs a sound field localization adjustment process to generate a third independent component from the second correlated components CC, CL1, and CR1 of Lch and Rch. Specifically, the Lch second correlated component CL1 is adjusted so that the output level of the R channel becomes 0, resulting in the Lch third independent component CL1. Similarly, the Rch second correlated component CR1 is adjusted so that the output level of the L channel becomes 0, resulting in the Rch third independent component CR1 (step S304).

[0099] In step S305, the third separation unit 303 separates the third independent components CL1, CR1 and the third correlated component CC from the Lch and Rch input signals il, ir from the second sound image localization adjustment unit. That is, the Lch third independent component CL1 and the Lch third correlated component CC are separated from the Lch input signal il, and the Rch third independent component CR1 and the Rch third correlated component CC are separated from the Rch input signal ir (step S305).

[0100] In step S306, the first separation unit 301 assigns the independent component IL and the uncorrelated component UL to the output control unit 321. The independent component IR and the uncorrelated component UR are assigned to the output control unit 322. The second separation unit 302 assigns the second independent component CL2 to the output control unit 323. The second independent component CR2 is assigned to the output control unit 324. The third separation unit 303 assigns the third independent component CL1 to the output control unit 325. The third independent component CR1 is assigned to the output control unit 326. Furthermore, the third correlated component CC is assigned to the output control unit 327 (step S306).

[0101] In step S307, the output control unit 321 controls the left side speaker 30SL to output the Lch end sound generated from the independent component IL and the Lch background sound generated from the uncorrelated component UL. Similarly, the output control unit 322 controls the right side speaker 30SR to output the Rch end sound generated from the independent component IR and the Rch background sound generated from the uncorrelated component UR.

[0102] Moreover, the output control unit 323 controls so that the Lch main sound generated from the second independent component CL2 is output from the left main speaker 30ML. Similarly, the output control unit 324 controls so that the Rch main sound generated from the second independent component CR2 is output from the right main speaker 30MR.

[0103] Furthermore, the output control unit 325 controls so that the Lch center sound generated from the third independent component CL1 is output from the left center speaker 30SCL. Similarly, the output control unit 326 controls so that the Rch center sound generated from the third independent component CR1 is output from the right center speaker 30SCR. The output control unit 327 controls so that the center sound generated from the third correlated component CC is output from the center speaker 30SC (step S307).

[0104] As a result, the left sound image LL of the end sound is localized at the installation position of the left side speaker 30SL, and the right sound image RR of the end sound is localized at the installation position of the right side speaker 30SR. Also, the sound image UU of the background sound is localized so as to spread in the space between the installation positions of the left side speaker 30SL and the right side speaker 30SR.

[0105] Further, the sound image L2 of the Lch main sound is localized at the installation position of the left main speaker 30ML, and the sound image R2 of the Rch main sound is localized at the installation position of the right main speaker 30MR.

[0106] Furthermore, the sound image L1 of the Lch center sound is localized at the installation position of the left center speaker 30SCL, the sound image R1 of the Rch center sound is localized at the installation position of the right center speaker 30SCR, and the sound image C of the center sound is localized at the installation position of the center speaker 30SC.

[0107] As described above, according to this embodiment, the independent components, uncorrelated components, and correlated components to be assigned to each speaker are separated from the left and right input signals, and further, the correlated components are separated into the second independent components and the second correlated components, so that the background sound generated from the uncorrelated components and the end sound generated from the independent components can be assigned to the left and right speakers and output. Also, the sound consisting of the correlated components can be assigned to the center speaker and output. This makes it possible to generate sound images localized in each speaker, and to prevent the sound images from overlapping each other. As a result, it is possible to suppress deterioration of the sound and a decrease in the sense of realism. Also, by generating independent components by the first separation unit and the second separation unit, it is possible to form sound images independent of the independent components from each speaker.

[0108] Furthermore, by separating the sound into independent components and correlated components by the third separation unit, it is possible to assign sound consisting of independent components to each speaker. Specifically, it is possible to assign sound consisting of independent components to the left side speaker, the right side speaker, the left main speaker, the right main speaker, the left center speaker, and the right center speaker. This makes it possible to form an independent sound image from each speaker, and to output high-quality sound with a high sense of presence.

[0109] (Fourth embodiment) 26 is a diagram showing an example of the configuration of a plurality of speakers of a display device 1 according to a fourth embodiment. In this embodiment, a configuration is shown in which one center speaker is removed from the speakers in the third embodiment. The display device 1 of this embodiment includes a left main speaker 40ML (an example of a first left speaker), a right main speaker 40MR (an example of a first right speaker), a left side speaker 40SL (an example of a second left speaker), and a right side speaker 40SR (an example of a second right speaker), as well as a left center speaker 40SCL (an example of a third left speaker) and a right center speaker 40SCR (an example of a third right speaker).

[0110] 27 is a diagram showing an example of the functional configuration of the DSP 21 according to the fourth embodiment. The DSP 21 of the fourth embodiment includes separation units 401-402, sound image localization adjustment units 411-412, and output control units 421-426. The third separation unit 403 and the output control unit assigned to the center speaker of the third embodiment are omitted.

[0111] The processing of the first separation unit 401, the second separation unit 402, the first sound image localization adjustment unit 411, and the second sound image localization adjustment unit 412 is the same as that of the third embodiment. Note that configurations that are not described in the fourth embodiment are omitted because they are the same as those of the third embodiment.

[0112] The third correlated component and the third independent component of the Lch output signal and the Rch output signal, which are the audio signals output from the second sound image localization adjustment section 412, are sent to the output control sections 425 and 426.

[0113] In the fourth embodiment, since there is no speaker to be assigned to the third correlation component, the left and right channel signals of the third correlation component are assigned to the left center speaker 40SCL and the right center speaker 40SCR, respectively. This allows the third correlation component to localize a sound image between the left center speaker 40SCL and the right center speaker 40SCR.

[0114] Although the audio device of the present embodiment is provided in a display device such as a television set, the functions of the audio device of the present invention may be provided in a speaker that is connected to a television set.

[0115] The program for realizing the functions of the display device 1 (DSP21) as described above may be provided by being recorded in a computer-readable recording medium such as a CD-ROM, a flexible disk (FD), a CD-R, or a digital versatile disk (DVD) in the form of a file that can be installed on a computer or that can be executed by a computer. The program may also be configured to be provided by being stored on a computer connected to a network such as the Internet and downloaded via the network. The program may also be configured to be provided or distributed via a network such as the Internet.

[0116] Although the embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the invention and its equivalents described in the claims. [Explanation of symbols]

[0117] 1...display device, 21...DSP (audio device), 23ML...left main speaker (first left speaker), 23MR...right main speaker (first right speaker), 23SL...left side speaker (second left speaker), 23SR...right side speaker (second right speaker), 101...separation unit, 102...sound image localization adjustment unit, 103...output control unit, 201, 201R...adaptive filter (filter unit), 211L, 211R...adaptive algorithm (coefficient update unit), C, L1, L2, LL, R1, R2, RR, UU...sound image

Claims

1. An audio device that performs processing to output audio from a plurality of speakers, a separation unit that separates, from each of a left input signal corresponding to a left channel and a right input signal corresponding to a right channel, an independent component that has no correlation between the left channel and the right channel and corresponds to an end sound whose sound image is localized at the left end or the right end of a predetermined region, an uncorrelated component that has no correlation between the left channel and the right channel and corresponds to a background sound whose sound image range is wider than the end sound, and a correlated component that has a correlation between the left channel and the right channel and corresponds to an intermediate sound whose sound image is localized inside the localization positions of the sound images of the left and right end sounds; a sound image localization adjustment unit that adjusts at least one of the correlated component and the independent component so that left and right sound images of the end sound generated from the independent component are localized at the left and right ends of the predetermined area, and a sound image of the intermediate sound generated from the correlated component is localized between the localization positions of the left and right sound images of the end sound; an output control unit that outputs the end sound, the background sound, and the intermediate sound from the plurality of speakers; An audio device comprising:

2. the plurality of speakers include a first left speaker, a first right speaker disposed to the right of the first left speaker, a second left speaker disposed to the left of the first left speaker, and a second right speaker disposed to the right of the first right speaker; the output control unit outputs the intermediate sound from the first left speaker and the first right speaker, and outputs the end sound and the background sound from the second left speaker and the second right speaker; the sound image localization adjustment unit adjusts the independent components so that a left sound image of the end sound is localized at an installation position of the second left speaker and a right sound image of the end sound is localized at an installation position of the second right speaker, and adjusts the correlated components so that a left end sound image of the intermediate sound is localized at an installation position of the first left speaker and a right end sound image of the intermediate sound is localized at an installation position of the first right speaker.

2. The audio device of claim 1.

3. the plurality of speakers includes a first left speaker and a first right speaker disposed to the right of the first left speaker, the output control unit outputs the end sound, the background sound, and the intermediate sound from the first left speaker and the first right speaker; the sound image localization adjustment unit adjusts the independent components so that a left sound image of the end sound is localized to the left of an installation position of the first left speaker and a right sound image of the end sound is localized to the right of an installation position of the first right speaker, and adjusts the correlated components so that a left end sound image of the intermediate sound is localized to the installation position of the first left speaker and a right end sound image of the intermediate sound is localized to the installation position of the first right speaker.

2. The audio device of claim 1.

4. the sound image localization adjustment unit adjusts the uncorrelated components so that the left end of the sound image of the background sound reaches the left side of the installation position of the first left speaker and the right end of the sound image reaches the right side of the installation position of the first right speaker.

4. An audio device as claimed in claim 3.

5. The separation unit includes a filter unit that applies a finite impulse response based on a predetermined coefficient to the left input signal and the right input signal to output an output signal corresponding to a component correlated with a target signal based on a difference between the left input signal and the right input signal, and a coefficient update unit that updates the coefficient so that a value of an error signal based on a difference between the target signal and the output signal is minimized.

5. An audio device according to claim 1.

6. An audio control method for outputting audio from a plurality of speakers, comprising: a step of separating, from each of a left input signal corresponding to a left channel and a right input signal corresponding to a right channel, an independent component corresponding to an end sound having no correlation between the left channel and the right channel and a sound image localized at the left end or the right end of a predetermined region, an uncorrelated component corresponding to a background sound having no correlation between the left channel and the right channel and a sound image range wider than that of the end sound, and a correlated component corresponding to an intermediate sound having a correlation between the left channel and the right channel and a sound image localized inside the localization position of the sound image of the left and right end sounds; adjusting at least one of the correlated component and the independent component so that left and right sound images of the end sound generated from the independent component are localized at the left and right ends of the predetermined area, and a sound image of the intermediate sound generated from the correlated component is localized between the localization positions of the left and right sound images of the end sound; outputting the end sound, the background sound, and the intermediate sound from the plurality of speakers; 23. An audio control method comprising:

7. An information processing device that performs processing for outputting audio from a plurality of speakers, a process of separating, from each of a left input signal corresponding to a left channel and a right input signal corresponding to a right channel, an independent component corresponding to an end sound whose sound image is localized at the left end or right end of a predetermined region, an uncorrelated component corresponding to a background sound whose sound image is localized at a wider range than the end sound whose sound image is localized at the left end or right end of a predetermined region, and a correlated component corresponding to an intermediate sound whose sound image is localized at a position inside the localization positions of the sound images of the left and right end sounds whose sound images are localized at a position inside the localization positions of the sound images of the left and right end sounds; a process of adjusting at least one of the correlated component and the independent component so that left and right sound images of the end sound generated from the independent component are localized at the left and right ends of the predetermined area, and a sound image of the intermediate sound generated from the correlated component is localized between the localization positions of the left and right sound images of the end sound; outputting the edge sound, the background sound, and the intermediate sound from the plurality of speakers; A program that executes the following.

8. a first separation unit that separates, from each of a left input signal corresponding to a left channel and a right input signal corresponding to a right channel, an independent component that has no correlation between the left channel and the right channel and localizes a sound image by one of the channels, an uncorrelated component that has no correlation between the left channel and the right channel and corresponds to a background sound in a wider range than the sound image of the independent component, and a correlated component that has a correlation between the left channel and the right channel and localizes a sound image inward from the sound image of the independent component by the left channel and the right channel; a first sound image localization adjustment unit that adjusts the correlated components to a second independent component that is generated on the left side by the left channel and on the right side by the right channel, and a second correlated component whose sound image is localized inward from the sound image of the second independent component; a second separation unit that separates the adjusted second independent component and the adjusted second correlated component into the second independent component and the second correlated component; and an output control unit that controls the components output from the first separation unit and the second separation unit to be output from a plurality of speakers. Audio equipment.

9. a second sound image localization adjustment unit that adjusts the second correlated component to a third independent component that is generated on the left side by the left channel and on the right side by the right channel, and a third correlated component whose sound image is localized inward from the sound image of the third independent component; a third separation unit that separates the adjusted third independent component and the adjusted third correlated component into the third independent component and the third correlated component, the output control unit controls the components output from the first separation unit, the second separation unit, and the third separation unit to be output from the plurality of speakers.

9. An audio device as claimed in claim 8.

10. An audio control method for outputting audio from a plurality of speakers, comprising: a first separation step of separating, from each of a left input signal corresponding to a left channel and a right input signal corresponding to a right channel, an independent component that has no correlation between the left channel and the right channel and localizes a sound image by one of the channels, an uncorrelated component that has no correlation between the left channel and the right channel and corresponds to a background sound in a wider range than the sound image of the independent component, and a correlated component that has a correlation between the left channel and the right channel and localizes a sound image inward from the sound image of the independent component by the left channel and the right channel; adjusting the correlated components to a second independent component generated on the left side by the left channel and on the right side by the right channel, and a second correlated component whose sound image is localized inward from the sound image of the second independent component; a second separation step of separating the adjusted second independent component and the adjusted second correlated component into the second independent component and the second correlated component; and an output control step of controlling the components output from the first separation step and the second separation step to be output from the plurality of speakers. Audio control methods.

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