Sound processing method, sound processing device, and program

Abstract

This sound processing method comprises: acquiring location information of a virtual wall arranged in a virtual space; acquiring information including sound transmission characteristics of the virtual wall, which are a first transmission characteristic of sound in instances of passing through the virtual wall along a first direction and a second transmission characteristic of sound in instances of passing through the virtual wall along a second direction that is the inverse direction of the first direction; acquiring information on a sound source location and a listening location; determining either the first transmission characteristic or the second transmission characteristic on the basis of the sound source location, the listening location, and the location information of the wall; and running sound processing on a sound signal of the sound source on the basis of the determined transmission characteristic.

Description

Sound processing method, sound processing device and program

[0001] An embodiment of the present invention relates to a sound processing method, a sound processing device, and a program.

[0002] Patent Document 1 discloses a virtual sound-insulating wall forming unit that blocks external sound and prevents sound from being emitted to the outside.

[0003] Patent Document 2 discloses an external information detection device that has a speaker installed inside a soundproof room and a microphone installed outside, allowing outside sounds to be heard from within the soundproof room without emitting noise from inside the soundproof room to the outside.

[0004] Patent Document 3 discloses a sound amplification area setting device that includes a detection means for detecting division information that divides a space surrounded by walls into a plurality of rooms, and a sound amplification means for amplifying an input audio signal into the space, and that amplifies a different audio signal for each of the divided rooms based on the division information.

[0005] JP 2010-107884 Utility Model Registration No. 3089220 JP 2001-128298

[0006] None of the inventions of Patent Documents 1 to 3 allows for the arbitrary setting of the passing characteristics of sound going out from a certain area and sound coming into the area from the outside.

[0007] One object of this embodiment is to provide a sound processing method that allows sound pass characteristics to be arbitrarily set according to the purpose.

[0008] A sound processing method according to one embodiment of the present invention acquires positional information of a virtual wall arranged in a virtual space, acquires information on sound pass characteristics of the virtual wall, including a first pass characteristic of sound when passing through the virtual wall along a first direction and a second pass characteristic of sound when passing through the virtual wall along a second direction opposite to the first direction, acquires information on a sound source position and a listening position, determines either the first pass characteristic or the second pass characteristic based on the sound source position, the listening position, and the positional information of the wall, and performs sound processing on a sound signal of the sound source based on the determined pass characteristic.

[0009] According to one embodiment of the present invention, sound transmission characteristics can be set arbitrarily depending on the purpose.

[0010] 1 is a block diagram showing the configuration of a PC 1. FIG. 2 is a plan view showing the configuration of a virtual space. FIG. 3 is a flowchart showing the operation of a processor 34. FIG. 4 is a list of transmission characteristics of virtual walls. FIG. 5 is a list of the relationship between first transmission characteristics and second transmission characteristics. FIG. 6 is a plan view showing the configuration of a virtual space in Modification 3. FIG. 7 is a plan view showing the configuration of a virtual space in Modification 5. FIG. 8 is a plan view showing the configuration of a virtual space in Modification 6. FIG. 9 is a plan view showing the configuration of a virtual space in Modification 8.

[0011] 1 is a block diagram showing the configuration of a PC 1. The PC 1 is an example of a sound processing device of the present invention and is a general-purpose information processing device. A user connects a head-mounted display (HMD) 51 and headphones 81 to the PC 1. The PC 1 includes a display interface (I / F) 31, a user I / F 32, a flash memory 33, a processor 34, a RAM 35, a communication I / F 36, and an audio I / F 37.

[0012] The display I / F 31 is connected to a display. The display I / F 31 of the PC 1 is connected to a head mounted display (HMD) 51, which is an example of a display. Note that, although the present embodiment shows an example in which the HMD 51 is connected to the PC 1, a display such as an LCD may also be connected to the PC 1.

[0013] The user I / F 32 is a keyboard, a mouse, or a touch panel that is stacked on a display. When the user I / F 32 is a touch panel, the user I / F 32 and the display constitute a GUI (Graphical User Interface).

[0014] The communication I / F 36 includes a network interface and is connected to a network such as the Internet via a router (not shown).

[0015] The audio I / F 37 has an audio terminal. The audio I / F 37 is connected to an audio device via an audio cable. In this embodiment, the audio I / F 37 of the PC 1 is connected to headphones 81. The audio I / F 37 outputs an audio signal to the headphones 81.

[0016] The processor 34 is composed of a CPU, a DSP, a SoC (System-on-a-Chip), or the like, and controls the components of the PC 1A and the PC 1B by reading a program stored in a flash memory 33, which is a storage medium, into a RAM 35. The flash memory 33 stores the program of this embodiment.

[0017] The processor 34 decodes audio data received from another device such as a server via the communication I / F 36, and outputs the decoded sound signal to the audio I / F 37. The audio data transmitted by another device such as a server includes a sound signal of a sound source located in a virtual space and position information of the sound source.

[0018] The processor 34 also decodes video data received from other devices via the communication I / F 36 and outputs the decoded video signal to the display via the display I / F 31. The video data transmitted by other devices such as a server includes information related to the shape of the virtual space, positional information of objects placed in the virtual space, CG images of the objects, etc. The information related to the shape of the virtual space (hereinafter referred to as space information) and the positional information of the objects are expressed in three-dimensional coordinates with a certain position as the origin.

[0019] 2 is a plan view showing the configuration of a virtual space, which includes a lobby space 101, a conference space 102, a terrace space 103, a meeting space 104, and an exhibition space 105.

[0020] The lobby space 101, conference space 102, terrace space 103, meeting space 104, and exhibition space 105 are each made up of virtual wall objects arranged in the virtual space.

[0021] The processor 34 renders a CG image of the virtual space based on the position information of the object, and generates a video image of the virtual space viewed in a predetermined direction from a certain viewpoint. Note that the video data transmitted by another device such as a server may be rendered video data.

[0022] The processor 34 performs level reduction processing on the sound signal of a sound source located in the virtual space according to the position of the sound source and the listening position. The level of the sound from the sound source decreases inversely proportional to the square of the distance from the sound source. To reproduce distance attenuation, the processor 34 performs level reduction processing, for example, inversely proportional to the square of the distance, according to the position of the sound source and the listening position. However, the level reduction processing does not necessarily have to be inversely proportional to the square of the distance. For example, the processor 34 may not attenuate the sound at a position very close to the sound source, but may perform level reduction processing that is inversely proportional to the distance at a medium distance and inversely proportional to the square of the distance at a long distance. The processor 34 may also perform level reduction processing based on a physical model that represents audible level attenuation according to distance.

[0023] The processor 34 also performs localization processing on the sound signals of sound sources located in the virtual space so that sound images are localized at the positions of the sound sources. The processor 34 performs localization processing based on, for example, HRTF (Head Related Transfer Function). HRTF represents a transfer function from a virtual sound source position to the user's right ear and left ear. For example, as shown in FIG. 2 , as viewed from the listening position L1, a first sound source 151 is located directly in front of the user, a second sound source 152 is located on the front right, and a third sound source 153 is located on the front left. The first sound source 151 is, for example, an announcement voice played in the lobby space 101. The second sound source 152 is the voice of a speaker in the conference space 102. The third sound source 153 is the voice of a conference participant in the meeting space 104.

[0024] The processor 34 performs binaural processing to convolve an HRTF on a sound signal corresponding to the first sound source 151 so that the sound is localized directly in front of the user. The processor 34 also performs binaural processing to convolve an HRTF on a sound signal corresponding to the second sound source 152 so that the sound is localized to the right in front of the user. The processor 34 also performs binaural processing to convolve an HRTF on a sound signal corresponding to the third sound source 153 so that the sound is localized to the left in front of the user. However, because the sound of the third sound source 153 is blocked by the walls of the meeting space 104 as described below, the processor 34 does not need to perform HRTF-based localization processing on the third sound source 153 when the listening position L1 is located outside the meeting space 104.

[0025] This allows the user to perceive as if they are at listening position L1 in the virtual space and are hearing the sound of first sound source 151 from directly in front of them. Also, the user can perceive as if they are at listening position L1 in the virtual space and are hearing the sound of second sound source 152 from directly in front of them.

[0026] Furthermore, the processor 34 performs sound processing based on the sound source position, the listening position, and wall position information. Figure 3 is a flowchart showing the operation of the sound processing method by the processor 34. The processor 34 acquires position information of a virtual wall (hereinafter referred to as a virtual wall) placed in a virtual space (S11). The processor 34 also acquires sound transmission characteristics of the virtual wall (S12). The transmission characteristics include a first transmission characteristic of sound when passing through the virtual wall along a first direction, and a second transmission characteristic of sound when passing through the virtual wall along a second direction opposite to the first direction.

[0027] 4 is a diagram showing the transmission characteristics of virtual walls. A lobby space 101, a conference space 102, a terrace space 103, a meeting space 104, and an exhibition space 105 each define transmission characteristics of the virtual walls that constitute them. A first transmission characteristic of sound passing through a virtual wall in a first direction is, for example, the transmission characteristic of sound entering the space (To Inside). A second transmission characteristic of sound passing through a virtual wall in a second direction opposite to the first direction is the transmission characteristic of sound leaving the space (To Outside).

[0028] The pass characteristics include a first characteristic "Insulation" of complete sound insulation, a second characteristic "Passage" of complete passage, and a third characteristic "Weak" other than complete sound insulation and complete passage.

[0029] For example, the first and second pass characteristics of the lobby space 101 are defined as the same "Weak". The first pass characteristic of the conference space 102 is complete sound insulation "Insulation", and the second pass characteristic of the conference space 102 is "Weak". The first and second pass characteristics of the terrace space 103 are the same "Passage". The first and second pass characteristics of the meeting space 104 are the same "Insulation". The first pass characteristic of the exhibition space 105 is "Insulation", and the second pass characteristic is "Passage". In this way, the first and second pass characteristics may be the same or different.

[0030] The processor 34 acquires information on the sound source position and the listening position (S13), and determines either the first passing characteristic or the second passing characteristic based on the sound source position, the listening position, and the position information of the virtual wall (S14).

[0031] 2 , there is a virtual wall of the lobby space 101 and a virtual wall of the conference space 102 between the second sound source 152 and the listening position L1. Therefore, the processor 34 determines the second pass characteristic (To Outside) of the conference space 102 to be "Weak" and the first pass characteristic (To Inside) of the lobby space 101 to be "Weak." In this case, the first pass characteristic (To Inside) and the second pass characteristic (To Outside) are both "Weak." Therefore, the processor 34 determines the "Weak" pass characteristic for the sound signal of the second sound source 152.

[0032] 5 is a diagram showing the relationship between the first and second pass characteristics. The processor 34 determines either the first pass characteristic (To Inside) or the second pass characteristic (To Outside) based on the relationship shown in FIG. 5. For example, when the first pass characteristic (To Inside) is "Insulation," the processor 34 determines the first pass characteristic to be "Insulation" even if the second pass characteristic is "Weak" or "Passage." Furthermore, when the second pass characteristic (To Outside) is "Insulation," the processor 34 determines the second pass characteristic to be "Insulation" even if the first pass characteristic is "Weak" or "Passage." When the first passing characteristic (To Inside) is “Weak”, the processor 34 determines the first passing characteristic to be “Weak” even if the second passing characteristic is “Passage”. When the second passing characteristic (To Outside) is “Weak”, the processor 34 determines the second passing characteristic to be “Weak” even if the first passing characteristic is “Passage”.

[0033] 2 , the virtual wall of the lobby space 101 and the virtual wall of the meeting space 104 are located between the third sound source 153 and the listening position L1. The processor 34 determines the pass characteristic of "Insulation" for the sound signal of the third sound source 153 by referring to the relationship between "Insulation" of the second pass characteristic (To Outside) of the meeting space 104 and "Weak" of the first pass characteristic (To Inside) of the lobby space 101.

[0034] 2, there is no virtual wall between the first sound source 151 and the listening position L1. In this case, the processor 34 determines the pass characteristic of "Passage" for the sound signal of the first sound source 151.

[0035] Then, the processor 34 performs sound processing on the sound signal of the sound source based on the determined pass characteristics (S15). If the determined pass characteristics are "Insulation", the processor 34 performs muting processing on the sound signal of the sound source. If the determined pass characteristics are "Passage", the processor 34 passes the sound signal of the sound source. If the determined pass characteristics are "Weak", the processor 34 performs filtering processing on the sound signal of the sound source.

[0036] The filtering process includes at least low-pass filtering. The low-pass filtering process attenuates the high frequencies of the sound from the sound source as it passes through the wall. In this case, the user can perceive the sound of the sound source as leaking through the wall. For example, the processor 34 applies low-pass filtering to the sound signal from the second sound source 152. This allows the user to perceive the speaker's voice as leaking through the wall of the conference space 102.

[0037] The filtering process may also include reverb processing. Reverb processing reproduces the reverberation of a space. Reverb processing parameters are determined for each space. The processor 34 applies reverb processing to the sound signal of the first sound source 151 using parameters corresponding to the lobby space 101. The processor 34 also applies reverb processing to the sound signal of the second sound source 152 using parameters corresponding to the conference space 102. At this time, it is preferable that the processor 34 does not apply reverb processing to the sound signal of the second sound source 152 using parameters corresponding to the lobby space 101. This allows users to perceive the speaker's voice, which is heard through the walls of the conference space 102, more realistically.

[0038] Furthermore, the filtering process is not limited to level attenuation processes such as low-pass filtering. For example, the filtering process may be amplification processes. As a result, the sound processing method of this embodiment can realize a wall with amplifying transmission characteristics that cannot be realized in a real space.

[0039] As shown in the example of FIG. 4 , the first pass characteristic (To Inside) and the second pass characteristic (To Outside) of each space may be the same or different. For example, the first pass characteristic (To Inside) of the conference space 102 is “Insulation,” and the second pass characteristic (To Outside) is “Weak.” This allows the voice of the speaker in the conference space 102 to leak out and be heard outside the conference space 102, but when inside the conference space 102, sounds outside the conference space 102 cannot be heard. Therefore, a person running a lecture in the conference space 102 can attract the interest of users outside the conference space 102 by letting them hear the speaker's voice. Furthermore, by not allowing users inside the conference space 102 to hear sounds outside the conference space 102, users can concentrate on the lecture.

[0040] Also, for example, the first pass characteristic (To Inside) and the second pass characteristic (To Outside) of the meeting space 104 are both "insulation." This means that the sound of the meeting in the meeting space 104 cannot be heard outside the meeting space 104, and if you are inside the meeting space 104, you cannot hear sounds outside the meeting space 104. Therefore, people holding a meeting in the meeting space 104 can concentrate on the meeting and ensure confidentiality by preventing the contents of the meeting from being overheard.

[0041] Furthermore, for example, by making the virtual walls that make up the meeting space 104 completely transparent, sound insulation can be ensured even in an open space. In other words, the sound processing method of this embodiment can realize a sound-insulating open space that cannot be realized in a real space.

[0042] Furthermore, for example, the first transmission characteristic (To Inside) of the exhibition space 105 is "Insulation," and the second transmission characteristic (To Outside) is "Passion." As a result, guidance audio and the like in the exhibition space 105 can be clearly heard outside the exhibition space 105, but sounds outside the exhibition space 105 cannot be heard when inside the exhibition space 105. Therefore, users of the exhibition space 105 can attract the interest of users outside the exhibition space 105 by letting them hear the guidance audio. Furthermore, users of the exhibition space 105 can prevent users inside the exhibition space 105 from hearing sounds outside the exhibition space 105, allowing them to concentrate on appreciating the exhibits. In other words, the sound processing method of this embodiment can realize a light-shielding wall that completely transmits sound, which is not possible in a real space.

[0043] As described above, the sound processing method of this embodiment can arbitrarily set the sound transmission characteristics according to the purpose. As a result, the sound processing method of this embodiment can provide a new customer experience by creating various virtual walls that were not possible with conventional methods, such as a light-shielding wall that completely transmits sound or an open space that completely blocks sound.

[0044] (Modification 1) The filtering process may include a first filtering process and a second filtering process that have relatively different intensities.

[0045] The strength is, for example, the height of the cutoff frequency in low-pass filtering. The higher the cutoff frequency, the weaker the filtering, and the lower the cutoff frequency, the stronger the filtering. A user of the sound processing method of this embodiment sets a low cutoff frequency for a virtual wall with high sound insulation, and a high cutoff frequency for a virtual wall with low sound insulation.

[0046] As a result, the sound processing method according to the first modification can change the sound insulation of the virtual wall.

[0047] (Variation 2) In the above-described embodiment, the processor 34 performs sound image localization processing on the sound signal of the sound source based on the sound source position and the listening position, and then performs sound processing based on the determined pass characteristics on the sound signal that has been subjected to the sound image localization processing. However, the processor 34 may also perform sound image localization processing on the sound signal that has been subjected to the sound processing based on the pass characteristics.

[0048] Furthermore, sound image localization processing is not essential. For example, sound whose quality has been degraded by filtering will have a lower sense of localization than sound that is not subjected to filtering. Therefore, for example, when the determined pass characteristics are "Weak," the processor 34 may not need to perform binaural processing in which an HRTF is convolved with the sound signal of the sound source. In this way, the sound processing method according to Modification 2 can reduce resource consumption of the processor 34 while suppressing the impact on the user's hearing by omitting sound image localization processing for leaking sounds whose quality is degraded.

[0049] (Variation 3) In the above embodiment, an example was shown in which the first pass characteristic corresponds to the pass characteristic of sound passing from a first area separated by a virtual wall to a second area different from the first area, and the second pass characteristic corresponds to the pass characteristic of sound passing from the second area to the first area. That is, in the above embodiment, an example was shown in which the first characteristic corresponds to the pass characteristic of sound entering a certain area (To Inside), and the second pass characteristic corresponds to the pass characteristic of sound leaving a certain area (To Outside).

[0050] However, the first and second pass characteristics do not need to be uniquely set for each area. Fig. 6 is a plan view showing the configuration of a virtual space in Modification Example 3. In the example of Fig. 6, a virtual wall 191 is defined to separate the lobby space 101 and the conference space 102. However, the virtual wall 191 separates half of the boundary between the lobby space 101 and the conference space 102. As a result, as shown in Fig. 6, at a listening position L1 separated by the virtual wall 191 from the position of the second sound source 152, the sound of the second sound source 152 is perceived as leaking out. At a listening position L2 visible from the position of the second sound source 152, the sound of the second sound source 152 can be clearly heard.

[0051] (Variation 4) The sound source includes a sound source corresponding to a speaker that is fixed as equipment. For example, the first sound source 151 shown in Fig. 2 is a sound source corresponding to a speaker that is fixed as equipment. The processor 34 may perform processing for the acoustic characteristics of the speaker on the sound signal of the sound source corresponding to the speaker, and may perform a level reduction process different from that for sound sources other than the speaker.

[0052] The processing of the acoustic characteristics of the speaker is, for example, high-pass filtering or distortion processing. High-pass filtering or distortion processing degrades the sound quality of the sound source. Generally, speakers fixed to the ceiling as equipment have low sound quality and low clarity. The processor 34 according to the fourth modification can reproduce the sound quality of such speakers fixed to the ceiling as equipment by processing the acoustic characteristics of the speaker.

[0053] Furthermore, the level reduction process that differs from that for sound sources other than speakers is a process that weakens distance attenuation. As described above, the level reduction process reduces the level in inverse proportion to the square of the distance from the sound source. However, the level reduction process for speakers weakens distance attenuation. This allows the processor 34 to further reproduce the sound quality of speakers fixed to the ceiling as equipment.

[0054] (Variation 5) The sound source may include environmental sound. Fig. 7 is a plan view showing the configuration of a virtual space in Variation 5. In the example of Fig. 7, an environmental sound source 171 is defined for the entire lobby space 101, and an environmental sound source 172 is defined for the entire terrace space 103. For example, the environmental sound source 171 for the lobby space 101 is background music. The environmental sound source 172 for the terrace space 103 is natural sounds such as birdsong. It is preferable not to perform localization processing on the environmental sound sources 171 and 172.

[0055] As a result, the sound processing method according to the fifth modification can reproduce the atmosphere of a lobby or a terrace.

[0056] (Variation 6) In the above-described embodiment, the processor 34 performs the first sound processing, such as muting or filtering, on the sound signal related to the direct sound of the sound source based on the determined pass characteristics. However, the processor 34 may perform the second sound processing on the sound signal related to the indirect sound of the sound source based on the determined pass characteristics.

[0057] Fig. 8 is a plan view showing the configuration of a virtual space in Modification 6. In the example of Fig. 8, the door to conference space 102 is open, and indirect sound from second sound source 152 reaches listening position L1. As second sound processing, processor 34 performs localization processing such that sound appears to arrive from the reflection position of second sound source 152 (the wall surface of meeting space 104 in the example of Fig. 8).

[0058] This allows users to more realistically perceive not only the sounds that leak through the walls of each space, but also the sounds that leak when the doors are open.

[0059] (Variation 7) The processor 34 according to Variation 7 acquires sound source information indicating pass characteristics determined for each sound source. The processor 34 performs sound processing on the sound signal of the sound source using the pass characteristics based on the sound source information. That is, pass characteristics may be determined for each sound source. For example, conversational voices may be blocked by the walls of each space, while environmental sounds such as background music may leak through the walls of each space and be heard. Alternatively, the voice of a speaker may be leaked through the walls of each space and be heard, while voices other than the speaker may be blocked by the walls of each space.

[0060] As a result, the sound processing method according to variant example 7 can provide a new customer experience by allowing various pass characteristics to be set for each sound source, such as a sound source that completely passes sound or a sound source that completely blocks sound.

[0061] (Variation 8) Fig. 9 is a plan view showing the configuration of a virtual space in Variation 8. In the example of Fig. 9, the virtual walls of the conference space 102 include a first virtual wall 102A and a second virtual wall 102B. The processor 34 acquires wall information indicating the pass characteristics defined for each of the first virtual wall 102A and the second virtual wall 102B. The processor 34 performs sound processing on the sound signal of the sound source using the pass characteristics based on the wall information. For example, in the example of Fig. 9, the wall information indicating the pass characteristics defined for the first virtual wall 102A is "Passage," which indicates complete passage. The wall information indicating the pass characteristics defined for the second virtual wall 102B is "Weak." The processor 34 applies filtering to the sound signal of the second sound source 152 so that the sound of the second sound source 152 leaks out and can be heard at a listening position L1 separated by the second virtual wall 102B when viewed from the position of the second sound source 152. The processor 34 passes the sound signal of the second sound source so that the sound of the second sound source 152 can be clearly heard at a listening position L2 separated by the first virtual wall 102A when viewed from the position of the second sound source 152.

[0062] As a result, the sound processing method according to variant 8 can provide a new customer experience by allowing various sound transmission characteristics to be set for each wall, such as a wall sound source that completely passes sound, or a wall that completely blocks sound, even within the same space.

[0063] The description of the present embodiment should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above-described embodiments. Furthermore, the scope of the present invention includes the scope equivalent to the claims.

[0064] 31: Display I / F, 32: User I / F, 33: Flash memory, 34: Processor, 35: RAM, 36: Communication I / F, 37: Audio I / F, 51: HMD, 81: Headphones, 101: Lobby space, 102: Conference space, 102A: First virtual wall, 102B: Second virtual wall, 103: Terrace space, 104: Meeting space, 105: Exhibition space, 151: First sound source, 152: Second sound source, 153: Third sound source

Claims

1. A sound processing method comprising: acquiring positional information of a virtual wall disposed in a virtual space; acquiring information on sound passing characteristics of the virtual wall, the information including a first passing characteristic of sound when passing through the virtual wall along a first direction and a second passing characteristic of sound when passing through the virtual wall along a second direction opposite to the first direction; acquiring information on a sound source position and a listening position; determining either the first passing characteristic or the second passing characteristic based on the sound source position, the listening position, and the wall position information; and performing sound processing on a sound signal of the sound source based on the determined passing characteristic.

2. The sound processing method according to claim 1, wherein the first pass characteristic and the second pass characteristic are different.

3. The sound processing method according to claim 1 or 2, wherein the pass characteristics include a first characteristic of complete sound insulation, a second characteristic of complete passage, and a third characteristic other than the complete sound insulation and complete passage, and when the determined pass characteristic is the first characteristic, a muting process is performed on the sound signal of the sound source, when the determined pass characteristic is the second characteristic, the sound signal of the sound source is allowed to pass, and when the determined pass characteristic is the third characteristic, a filter process is performed on the sound signal of the sound source.

4. The sound processing method according to claim 3, wherein the filtering process includes a first filtering process and a second filtering process having relatively different intensities.

5. The sound processing method according to claim 1 or 2, further comprising the step of: performing sound image localization processing on the sound signal of the sound source based on the sound source position and the listening position.

6. A sound processing method as described in claim 1 or claim 2, wherein the first pass characteristic corresponds to the pass characteristic of a sound passing from a first area separated by the virtual wall to a second area different from the first area, and the second pass characteristic corresponds to the pass characteristic of a sound passing from the second area to the first area.

7. The sound processing method according to claim 1 or 2, wherein the sound source includes a sound source corresponding to a speaker fixed as equipment, and a sound signal of the sound source corresponding to the speaker is subjected to processing for the acoustic characteristics of the speaker, and a level reduction processing different from that for sound sources other than the speaker is performed.

8. The sound processing method according to claim 1 or 2, wherein the sound source includes an environmental sound.

9. A sound processing method as described in claim 1 or claim 2, comprising: applying a first sound processing to a sound signal relating to a direct sound of the sound source based on the determined pass characteristics; and applying a second sound processing to a sound signal relating to an indirect sound of the sound source based on the determined pass characteristics.

10. A sound processing method according to claim 1 or 2, further comprising the steps of: acquiring sound source information indicating a pass characteristic determined for each sound source; and performing sound processing on a sound signal of the sound source using the pass characteristic based on the sound source information.

11. The sound processing method according to claim 1 or claim 2, wherein the virtual wall includes a first wall and a second wall, wall information indicating pass characteristics respectively determined for the first wall and the second wall is acquired, and sound processing is performed on the sound signal of the sound source using the pass characteristics based on the wall information.

12. A sound processing device having a processor that acquires position information of a virtual wall arranged in a virtual space; acquires information on sound passing characteristics of the virtual wall, the information including a first passing characteristic of sound when passing through the virtual wall along a first direction and a second passing characteristic of sound when passing through the virtual wall along a second direction opposite to the first direction; acquires information on a sound source position and a listening position; determines either the first passing characteristic or the second passing characteristic based on the sound source position, the listening position, and the position information of the wall; and performs sound processing on a sound signal of the sound source based on the determined passing characteristic.

13. The sound processing device according to claim 12, wherein the first pass characteristic and the second pass characteristic are different from each other.

14. A sound processing device as described in claim 12 or claim 13, wherein the pass characteristics include a first characteristic of complete sound insulation, a second characteristic of complete passage, and a third characteristic other than the complete sound insulation and complete passage, and the processor performs a muting process on the sound signal of the sound source when the determined pass characteristic is the first characteristic, passes the sound signal of the sound source when the determined pass characteristic is the second characteristic, and performs a filtering process on the sound signal of the sound source when the determined pass characteristic is the third characteristic.

15. The sound processing device according to claim 14, wherein the filtering process includes a first filtering process and a second filtering process having relatively different intensities.

16. The sound processing device according to claim 12 or 13, wherein the processor performs sound image localization processing on the sound signal of the sound source based on the sound source position and the listening position.

17. A sound processing device as described in claim 12 or claim 13, wherein the first pass characteristic corresponds to the pass characteristic of sound passing from a first area separated by the virtual wall to a second area different from the first area, and the second pass characteristic corresponds to the pass characteristic of sound passing from the second area to the first area.

18. The sound processing device according to claim 12 or 13, wherein the sound source includes a sound source corresponding to a speaker fixed as equipment, and the processor processes the sound signal of the sound source corresponding to the speaker in accordance with the acoustic characteristics of the speaker, and performs a level reduction process different from that performed on sound sources other than the speaker.

19. The sound processing device according to claim 12 or 13, wherein the sound source includes an environmental sound.

20. A program that causes a sound processing device to execute the following processes: acquire position information of a virtual wall arranged in a virtual space; acquire information on sound passing characteristics of the virtual wall, the information including a first passing characteristic of sound when passing through the virtual wall along a first direction and a second passing characteristic of sound when passing through the virtual wall along a second direction opposite to the first direction; acquire information on a sound source position and a listening position; determine either the first passing characteristic or the second passing characteristic based on the sound source position, the listening position, and the position information of the wall; and perform sound processing on the sound signal of the sound source based on the determined passing characteristic.

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