Sound field expansion method, device, audio device and computer-readable storage medium

Abstract

The present invention discloses a sound field expansion method, apparatus, audio device, and computer-readable storage medium, belonging to the technical field of audio processing. The sound field expansion method provided by the present invention includes the following steps: obtaining a target transfer function between a loudspeaker at an expansion target position and the user's binaural ears; performing sound field expansion processing on an input signal received by a near-ear open audio device according to the target transfer function to obtain an output signal; playing the output signal through the near-ear open audio device so that the binaural ears of a user wearing the near-ear open audio device receive sound signals from the expansion target position. The present invention provides a sound field expansion method for near-ear open audio devices, enabling users to feel a wider effect than the actual loudspeaker position when listening to audio while wearing near-ear open audio devices.

Description

Technical Field

[0001] The present invention relates to the technical field of audio processing, and in particular to a sound field expansion method, device, audio device and computer-readable storage medium. Background Art

[0002] Sound field expansion refers to an acoustic phenomenon in which the perceived sound field during listening is wider than the actual position of the speaker. Sound field expansion is similar to a virtual speaker, which can expand the sound source position to a wider position than the actual position of the speaker, that is, making the sound played by the sound source sound equivalent to the sound emitted from a virtual speaker at a wider position in the human ear.

[0003] Currently, sound field expansion technology is mainly applied to far-field sound sources, such as scenarios using speakers. In the prior art, there is not much attention paid to the sound field expansion function of near-ear open audio devices such as VR (Virtual Reality) and AR (Augmented Reality).

[0004] In recent years, with the increasing market shipments of near-ear open audio devices, adding a sound field expansion function to near-ear open audio devices can obviously have a positive impact on the sales market and user groups of near-ear open audio devices. Summary of the Invention

[0005] The main purpose of the present invention is to provide a sound field expansion method, device, audio device and computer-readable storage medium, aiming to add a sound field expansion function to near-ear open audio devices.

[0006] To achieve the above object, the present invention provides a sound field expansion method, and the sound field expansion method includes the following steps:

[0007] Obtain a target transfer function between a speaker at an extended target position and the user's binaural ears;

[0008] Perform sound field expansion processing on the input signal received by the near-ear open audio device according to the target transfer function to obtain an output signal;

[0009] Play the output signal through the near-ear open audio device, so that the binaural ears of the user wearing the near-ear open audio device receive sound signals from the extended target position.

[0010] Optionally, the step of obtaining the target transfer function between the speaker at the extended target position and the user's binaural ears includes:

[0011] Obtain an artificial head transfer function and a free field transfer function;

[0012] Determine the target transfer function between the loudspeaker at the extended target position and the user's binaural ears according to the artificial head transfer function and the free field transfer function.

[0013] Optionally, the step of determining the target transfer function between the loudspeaker at the extended target position and the user's binaural ears according to the artificial head transfer function and the free field transfer function includes:

[0014] Perform an inverse operation on the free field transfer function to obtain the free field inverse transfer function;

[0015] Multiply the artificial head transfer function by the free field inverse transfer function to obtain the target transfer function between the loudspeaker at the extended target position and the user's binaural ears.

[0016] Optionally, the step of obtaining the artificial head transfer function includes:

[0017] When the loudspeaker of the near-ear open audio device is placed at the extended target position and the loudspeaker outputs a sound signal, measure the artificial head transfer function through a preset microphone in the preset ear canal of the artificial head.

[0018] Optionally, the step of obtaining the free field transfer function includes:

[0019] When the artificial head is removed and the loudspeaker outputs a sound signal, measure the free field transfer function through preset microphones placed at the left and right ear positions before the artificial head is removed.

[0020] Optionally, the step of performing sound field expansion processing on the input signal received by the near-ear open audio device according to the target transfer function to obtain an output signal includes:

[0021] Multiply the input signal received by the near-ear open audio device by the target transfer function to obtain the output signal.

[0022] Optionally, the step of performing sound field expansion processing on the input signal received by the near-ear open audio device according to the target transfer function to obtain an output signal further includes:

[0023] Perform reduced-order fitting on the target transfer function to obtain a low-order fitting transfer function;

[0024] Multiply the input signal received by the near-ear open audio device by the low-order fitting transfer function to obtain the output signal.

[0025] In addition, to achieve the above object, the present invention further provides a sound field expansion device, and the sound field expansion device includes:

[0026] An acquisition module, which is used to acquire a target transfer function between a loudspeaker at an extended target position and the user's two ears;

[0027] A processing module, which is used to perform sound field expansion processing on an input signal received by a near-ear open audio device according to the target transfer function to obtain an output signal;

[0028] A playback module, which is used to play the output signal through the near-ear open audio device, so that the two ears of the user wearing the near-ear open audio device receive sound signals from the extended target position.

[0029] In addition, to achieve the above object, the present invention further provides an audio device, which includes: a memory, a processor, and a sound field expansion program stored on the memory and executable on the processor. When the sound field expansion program is executed by the processor, the steps of the sound field expansion method described above are implemented.

[0030] In addition, to achieve the above object, the present invention further provides a computer-readable storage medium, on which a sound field expansion program is stored. When the sound field expansion program is executed by a processor, the steps of the sound field expansion method described above are implemented.

[0031] The present invention proposes a sound field expansion method, device, audio device, and computer-readable storage medium, which solve the technical problem that existing near-ear open audio devices do not have a sound field expansion function. In the sound field expansion method, first, a target transfer function between a loudspeaker at an extended target position and the user's two ears is acquired; then, sound field expansion processing is performed on an input signal received by a near-ear open audio device according to the target transfer function to obtain an output signal; finally, the output signal is played through the near-ear open audio device, so that the two ears of the user wearing the near-ear open audio device receive sound signals from the extended target position. The present invention calculates the acoustic transfer function in different application scenarios through a sound source simulation method, which can eliminate the interference of the near-ear open audio device itself on the sound signal, and can also simulate the actual loudspeaker as a loudspeaker at the extended target position. When it is difficult to adjust the distance between the loudspeaker of the near-ear open audio device and the wearing user, the listening feeling when the sound played by the near-ear open audio device is transmitted to the user's two ears becomes wider, significantly improving the use experience of the user group of the near-ear open audio device and enhancing the function of the near-ear open audio device. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic flowchart of an embodiment of the sound field expansion method of the present invention;

[0033] Figure 2Schematic diagram of an application scenario of an embodiment of the sound field expansion method of the present invention;

[0034] Figure 3 Schematic diagram of functional modules of an embodiment of the sound field expansion device of the present invention;

[0035] Figure 4 Schematic diagram of the structure of an audio device involved in the solution of the embodiment of the present invention.

[0036] The realization of the object, functional characteristics and advantages of the present invention will be further described with reference to the embodiments and the accompanying drawings. Detailed implementation manners

[0037] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0038] The main solution of the embodiment of the present invention is: a sound field expansion method, the sound field expansion method includes the following steps:

[0039] Obtain the target transfer function between the loudspeaker at the expansion target position and the user's binaural ears;

[0040] Perform sound field expansion processing on the input signal received by the near-ear open audio device according to the target transfer function to obtain an output signal;

[0041] Play the output signal through the near-ear open audio device, so that the binaural ears of the user wearing the near-ear open audio device receive the sound signal from the expansion target position.

[0042] Since the sound field expansion technology in the prior art is mainly applied to far-field sound sources, such as the scenario of using speakers, there is not much attention paid to the sound field expansion function of near-ear open audio devices such as VR (Virtual Reality) and AR (Augmented Reality). In recent years, with the increasing market shipments of near-ear open audio devices, adding a sound field expansion function to near-ear open audio devices can obviously have a positive impact on the sales market and user groups of near-ear open audio devices.

[0043] The present invention provides a sound field expansion method. By calculating the acoustic transfer function in different application scenarios through the sound source simulation method, it can eliminate the interference of the near-ear open audio device itself on the sound signal, and can also simulate the actual loudspeaker as the loudspeaker at the expansion target position. When it is difficult to adjust the distance between the loudspeaker of the near-ear open audio device and the wearing user, the listening effect when the sound played by the near-ear open audio device is transmitted to the user's binaural ears becomes wider, effectively improving the listening feeling of the user group of the near-ear open audio device and enhancing the function of the near-ear open audio device.

[0044] An embodiment of the present invention provides a sound field expansion method. Refer to Figure 1 , Figure 1 which is a schematic flowchart of an embodiment of a sound field expansion method of the present invention.

[0045] In this embodiment, the sound field expansion method includes:

[0046] Step S10: Obtain the target transfer function between the speaker at the expansion target position and the user's binaural ears;

[0047] In this embodiment, the execution entity is a near-ear open audio device. The near-ear open audio device includes, but is not limited to, products such as AR, VR, smart audio glasses, neckband speakers, open headphones, etc. Compared with the speaker scenario, the position of the speaker or loudspeaker of the near-ear open audio device is closer to the human ear, and the near-ear open device is generally an all-in-one machine, and the distance between its sound generating module and the human ear is almost non-adjustable. That is, generally, the sound heard by the human ear from the near-ear open audio device is near-field sound effects. It can be understood in combination with Figure 2 for understanding. Figure 2 is a schematic diagram of an application scenario provided in this embodiment. Assuming that the relative position between the position of the user's head and the device speaker is as Figure 2 shown, then when the user uses the near-ear open audio device, even if the wearing position of the sound generating module can be finely adjusted, it cannot bring the listening feeling that the dotted-line speaker position in the figure can produce to the user. The user can only feel the near-field listening feeling from the actual speaker. When the user wants to feel a wider sound effect, for example, when the user wants to hear the sound emitted from the Figure 2 dotted-line speaker position in, the position can be set as the expansion target position. The target transfer function between the speaker at the expansion target position and the user's binaural ears represents the transfer function of the sound from the speaker at this position to the human ear after the sound is generated.

[0048] It should be noted that each transfer function mentioned in this embodiment is an acoustic transfer function. The acoustic transfer function is the transfer function from a sound source to the reproduction area. The transfer function refers to the ratio of the Laplace transform (or z-transform) of the response (i.e., output) of a linear system under zero initial conditions to the Laplace transform of the excitation (i.e., input) quantity. In this embodiment, the target transfer function between the near-ear open audio device and the user's binaural ears is the transfer function from the output sound source (i.e., the speaker or loudspeaker) of the near-ear open audio device to the user's binaural ears, which is used to reflect the change of the output signal during the process of the output signal of the near-ear open audio device being transmitted to the user's binaural ears.

[0049] Based on this, in a feasible embodiment, the above step S10 may include:

[0050] Step S11: Obtain the artificial head transfer function and the free field transfer function;

[0051] Step S12: Determine the target transfer function between the speaker at the extended target position and the user's binaural ears according to the artificial head transfer function and the free field transfer function.

[0052] It should be noted that in this embodiment, the above target transfer function can be understood as the influence of the user's head contour on the sound signal transmission result, and this target transfer function cannot be directly obtained, but is calculated after obtaining two different acoustic transfer functions based on two different sound transmission scenarios. Among them, the artificial head transfer function is the acoustic transfer function measured by the preset microphone in the artificial head ear canal when the speaker of the near-ear open audio device is placed at the extended target position (i.e., the position of the dotted-line speaker in Figure 2 ), and the speaker outputs a sound signal, which includes the influence of the sound generating module and the artificial head on the sound transmission result; the free field transfer function is the acoustic transfer function measured by the preset microphones placed at the left and right ear positions before the artificial head is removed when the speaker outputs a sound signal, which includes the influence of the sound generating module on the sound transmission result.

[0053] Furthermore, in a feasible embodiment, the step of obtaining the artificial head transfer function in the above step S11 may include:

[0054] Step S111: When the speaker of the near-ear open audio device is placed at the extended target position and the speaker outputs a sound signal, measure the artificial head transfer function through the preset microphone in the preset artificial head ear canal.

[0055] It should be noted that in this embodiment, the preset artificial head is an auxiliary device constructed to simulate the user's head for assisting in measuring the acoustic transfer function. It can simulate the scenario where the user receives the sound signal emitted by the speaker of the near-ear open audio device. The preset artificial head is provided with left and right ears and ear canals, and microphones for receiving sound signals can be pre-placed in the ear canals.

[0056] As an example, in combination with the Figure 2 application scenario shown, place the near-ear open audio device at the virtual speaker setting position, that is, the position of the dotted-line speaker in Figure 2 , and use the two preset microphones in the preset artificial head ear canal to measure the acoustic transfer function from the sound source (i.e., the speaker or horn of the near-ear open audio device) to the binaural ears of the preset artificial head, and record this acoustic transfer function as H1.

[0057] Furthermore, in a feasible embodiment, the step of obtaining the free field transfer function in the above step S11 may include:

[0058] Step S112, when the artificial head is removed and the loudspeaker outputs a sound signal, the free-field transfer function is measured by preset microphones placed at the left and right ear positions before the artificial head is removed.

[0059] As an example, in combination with Figure 2 the application scenario shown, first, two microphones consistent with those in the ear canals of the preset artificial head in the above step S111 are placed at the left and right ear positions of the preset artificial head, and then the preset artificial head is removed. The near-ear open audio device is still placed at the virtual loudspeaker setting position, that is, Figure 2 the position where the dotted-line loudspeaker is located in, and the acoustic transfer function of the sound source (i.e., the loudspeaker or speaker of the near-ear open audio device) when working in the free field is measured by two microphones not affected by the artificial head, and this acoustic transfer function is denoted as H2.

[0060] Furthermore, in a feasible embodiment, the above step S12 may include:

[0061] Step S121, perform an inverse operation on the free-field transfer function to obtain a free-field inverse transfer function;

[0062] Step S122, multiply the artificial head transfer function by the free-field inverse transfer function to obtain a target transfer function between the loudspeaker at the extended target position and the user's both ears.

[0063] In this embodiment, first, an inverse operation is performed on the free-field transfer function H2 obtained in the above step S112, which includes the influence of the sound generation module on the sound transmission result, to obtain a free-field inverse transfer function, denoted as H2'. Then, the artificial head transfer function H1 obtained in the above step S111, which includes the influence of the sound generation module and the artificial head on the sound transmission result, is multiplied by H2' to obtain the target transfer function H. It should be noted that H2' obtained after the inverse operation can eliminate the influence of the sound generation module on the sound transmission result. After multiplying it by H1, the part of the influence of the sound generation module on the sound transmission result in H1 can be eliminated, and the influence of the artificial head on the sound transmission result is retained as the target transfer function H.

[0064] Step S20, perform sound field expansion processing on the input signal received by the near-ear open audio device according to the target transfer function to obtain an output signal;

[0065] It can be understood that since the speaker or horn of the near-ear open audio device is not an ideal sound source, the transfer function of the sound generation module itself will affect the result of sound transmission during the sound transmission process. Before generating the output signal, the input signal is first subjected to sound field expansion processing, that is, to cancel the interference of the transfer function of the sound generation module itself on the sound signal during the transmission process after the output signal is played. That is, the output signal is obtained by subjecting the input signal to sound field expansion processing. It can cancel the influence of the transfer function of the sound generation module itself on the sound signal during the sound transmission process and retain the influence of the artificial head on the sound transmission result. When the output signal enters the user's ears, it can make the user feel that the source of the sound signal is the speaker at the extended target position at the far end.

[0066] Further, in a feasible embodiment, the above step S20 may include:

[0067] Step S21, multiplying the input signal received by the near-ear open audio device by the target transfer function to obtain an output signal.

[0068] As can be seen from the above steps, the target transfer function H represents the influence of the artificial head on the sound transmission result, and the input signal is set based on the actual speaker. If it is directly output without processing, the user's listening experience cannot be changed, and the user will still feel the near-field sound effect. However, if H is applied to the input signal and then output, the output signal can be approximated to the sound signal output by the speaker at the extended target position. When the user's ears receive this signal, what is felt is no longer the near-field sound effect reflected by the distance between the actual speaker and the user's ears, but the broader far-field sound effect from the virtual speaker. This embodiment reasonably utilizes the influence of the artificial head on the sound transmission result.

[0069] As an example, in combination with Figure 2 the application scenario shown, when the input signal X of the near-ear open audio device is given, the input signal X is processed by the sound field expansion algorithm module and then output through the SPK (speaker), and the output signal is transmitted to the human ear through the human head model. Among them, the basic idea implemented by the sound field expansion algorithm module is to first obtain the transfer function H of the sound from the SPK to the human ear after the SPK emits sound, and then the sound field expansion algorithm module applies this transfer function H to the input signal X. After the two act together, the effect of sound field expansion can be achieved, that is, the output signal Y = XH is the signal after sound field expansion.

[0070] Further, in another feasible embodiment, the above step S20 may further include:

[0071] Step S22, performing reduced-order fitting on the target transfer function to obtain a low-order fitting transfer function;

[0072] Step S23: Multiply the input signal received by the near-ear open audio device by the low-order fitting transfer function to obtain an output signal.

[0073] It should be noted that the target transfer function H in this embodiment can be regarded as similar to the function of a filter. When its order is too high, it can be reduced-order fitted to obtain a low-order fitting transfer function B. After applying B to the input signal and then outputting, the output signal can be approximated to the sound signal output by the speaker at the extended target position. When the user's ears receive this signal, what is felt is no longer the near-field sound effect reflected by the actual distance between the speaker and the user's ears, but a broader far-field sound effect from the virtual speaker. This embodiment reasonably utilizes the influence of the artificial head on the sound transmission result.

[0074] As an example, in combination with Figure 2 the application scenario shown, when the input signal X of the near-ear open audio device is given, the input signal X is processed by the sound field expansion algorithm module and then output by the SPK (speaker). The output signal is transmitted through the human head model to the human ear. Among them, the basic idea implemented by the sound field expansion algorithm module is to first obtain the transfer function H of the sound from the SPK to the human ear after the SPK emits sound. If the order of the transfer function H is too high, it is subjected to a reduced-order fitting process to obtain a low-order fitting transfer function B. Then, the sound field expansion algorithm module applies this low-order fitting transfer function B to the input signal X. After their combined action, the effect of sound field expansion can be achieved, that is, the output signal Y = XB is the signal after sound field expansion.

[0075] Step S30: Play the output signal through the near-ear open audio device so that the ears of the user wearing the near-ear open audio device receive the sound signal from the extended target position.

[0076] It should be noted that in this embodiment, the sound signal received by the ears of the user wearing the near-ear open audio device still comes from the actual speaker or speaker on the near-ear open audio device. Here, it is only to reflect the user's listening experience. In fact, there is no speaker at the extended target position. It's just that this embodiment can make the user feel that the sound signal received by their ears comes from the speaker located at this extended target position.

[0077] It can be understood that since the output signal has been subjected to sound field expansion processing based on the sound field expansion algorithm provided in this embodiment before being output via the speaker, the influence of the near-ear open audio device itself on the sound transmission result is eliminated. Therefore, when the output signal enters the user's ears, the user can perceive that the sound signal comes from a far end and is emitted by a virtual speaker located at the extended target position. In fact, the sound signal is still emitted by the actual speaker on the near-ear open audio device that is very close to the user, but it can bring a broader listening experience to the user.

[0078] This embodiment proposes a sound field expansion method, which solves the technical problem that the near-ear open audio device in the prior art does not have the function of sound field expansion. In the sound field expansion method, first, the target transfer function between the speaker at the extended target position and the user's ears is obtained; then, the input signal received by the near-ear open audio device is subjected to sound field expansion processing according to the target transfer function to obtain an output signal; finally, the output signal is played through the near-ear open audio device so that the ears of the user wearing the near-ear open audio device receive the sound signal from the extended target position. By calculating the transfer function in different application scenarios through the method of sound source simulation, this embodiment can eliminate the interference of the near-ear open audio device itself on the sound signal, and can also simulate the actual speaker as the speaker at the extended target position. When it is difficult to adjust the distance between the speaker of the near-ear open audio device and the wearing user, the listening feeling when the sound played by the near-ear open audio device reaches the user's ears becomes broader, significantly improving the use experience of the user group of the near-ear open audio device and enhancing the function of the near-ear open audio device.

[0079] In addition, the embodiment of the present invention also proposes a sound field expansion device, referring to Figure 3 , Figure 3 which is a schematic diagram of the functional modules of an embodiment of a sound field expansion device of the present invention.

[0080] In this embodiment, the sound field expansion device includes:

[0081] An acquisition module 10, which is used to acquire the target transfer function between the speaker at the extended target position and the user's ears;

[0082] A processing module 20, which is used to perform sound field expansion processing on the input signal received by the near-ear open audio device according to the target transfer function to obtain an output signal;

[0083] A playback module 30, which is used to play the output signal through the near-ear open audio device so that the ears of the user wearing the near-ear open audio device receive the sound signal from the extended target position.

[0084] Optionally, the obtaining module 10 is further configured to obtain a target transfer function between the near-ear open audio device and the user's binaural ears.

[0085] Optionally, the obtaining module 10 includes:

[0086] An acquisition unit configured to obtain an artificial head transfer function and a free field transfer function;

[0087] A first calculation unit configured to determine a target transfer function between the loudspeaker at the extended target position and the user's binaural ears according to the artificial head transfer function and the free field transfer function.

[0088] Optionally, the first calculation unit is further configured to perform an inverse operation on the free field transfer function to obtain a free field inverse transfer function;

[0089] The first calculation unit is further configured to multiply the artificial head transfer function by the free field inverse transfer function to obtain a target transfer function between the loudspeaker at the extended target position and the user's binaural ears.

[0090] Optionally, the acquisition unit is further configured to measure the artificial head transfer function through a preset microphone in a preset artificial head ear canal when the loudspeaker of the near-ear open audio device is placed at the extended target position and the loudspeaker outputs a sound signal.

[0091] Optionally, the acquisition unit is further configured to measure the free field transfer function through preset microphones placed at the left and right ear positions before the artificial head is removed when the artificial head is removed and the loudspeaker outputs a sound signal.

[0092] Optionally, the processing module 20 includes:

[0093] A second calculation unit configured to multiply the input signal received by the near-ear open audio device by the target transfer function to obtain an output signal.

[0094] Optionally, the second calculation unit is further configured to perform a reduced-order fitting on the target transfer function to obtain a low-order fitting transfer function;

[0095] The second calculation unit is further configured to multiply the input signal received by the near-ear open audio device by the low-order fitting transfer function to obtain an output signal.

[0096] The extended content of the specific implementation manner of the sound field expansion device is basically the same as that of the embodiments of the above sound field expansion method, and the sound field expansion device can achieve the same technical effects as those of the embodiments of the above sound field expansion method, which will not be elaborated here.

[0097] In addition, an embodiment of the present invention further provides an audio device. Refer to Figure 4 , Figure 4 , which is a schematic structural diagram of the audio device involved in the solution of the embodiment of the present invention.

[0098] As Figure 4 shown, the audio device may include: a processor 1001, a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. Among them, the processor 1001 may be a central processing unit (CPU). The communication bus 1002 is used to implement connection communication between these components. The user interface 1003 may include a display screen (Display) and an input unit such as a keyboard (Keyboard). Optionally, the user interface 1003 may further include a standard wired interface and a wireless interface. The network interface 1004 may optionally include a standard wired interface and a wireless interface (such as a wireless fidelity (WI-FI) interface). The memory 1005 may be a high-speed random access memory (Random Access Memory, RAM) or a stable non-volatile memory (Non-Volatile Memory, NVM), such as a disk memory. Optionally, the memory 1005 may also be a storage device independent of the aforementioned processor 1001.

[0099] Those skilled in the art can understand that Figure 4 the structure shown in

[0100] does not constitute a limitation on the audio device, and it may include more or fewer components than shown in the figure, or combine certain components, or have different component arrangements. Figure 4 As

[0101] shown, the memory 1005, as a storage medium, may include an operating system, a data storage module, a network communication module, a user interface module, and a sound field expansion program. Figure 4 In the audio device shown in

[0102] the network interface 1004 is mainly used for data communication with other devices; the user interface 1003 is mainly used for data interaction with users; in this embodiment, the processor 1001 and the memory 1005 may be disposed in the audio device. The audio device calls the sound field expansion program stored in the memory 1005 through the processor 1001 and performs the following operations:

[0103] Perform sound field expansion processing on the input signal received by the near-ear open audio device according to the target transfer function to obtain an output signal;

[0104] Play the output signal through the near-ear open audio device so that the user's binaural ears wearing the near-ear open audio device receive sound signals from the expanded target position.

[0105] Further, the processor 1001 can call the sound field expansion program stored in the memory 1005 and also perform the following operations:

[0106] Obtain the artificial head transfer function and the free field transfer function;

[0107] Determine the target transfer function between the loudspeaker at the expanded target position and the user's binaural ears according to the artificial head transfer function and the free field transfer function.

[0108] Further, the processor 1001 can call the sound field expansion program stored in the memory 1005 and also perform the following operations:

[0109] Perform an inverse operation on the free field transfer function to obtain the free field inverse transfer function;

[0110] Multiply the artificial head transfer function by the free field inverse transfer function to obtain the target transfer function between the loudspeaker at the expanded target position and the user's binaural ears.

[0111] Further, the processor 1001 can call the sound field expansion program stored in the memory 1005 and also perform the following operations:

[0112] When the loudspeaker of the near-ear open audio device is placed at the expanded target position and the loudspeaker outputs a sound signal, measure the artificial head transfer function through the preset microphone in the preset artificial head ear canal.

[0113] Further, the processor 1001 can call the sound field expansion program stored in the memory 1005 and also perform the following operations:

[0114] When the artificial head is removed and the loudspeaker outputs a sound signal, measure the free field transfer function through the preset microphones placed at the left and right ear positions before the artificial head is removed.

[0115] Further, the processor 1001 can call the sound field expansion program stored in the memory 1005 and also perform the following operations:

[0116] Multiply the input signal received by the near-ear open audio device by the target transfer function to obtain an output signal.

[0117] Further, the processor 1001 may call the sound field extension program stored in the memory 1005 and further perform the following operations:

[0118] Perform a reduced-order fitting on the target transfer function to obtain a low-order fitted transfer function;

[0119] Multiply the input signal received by the near-ear open audio device by the low-order fitted transfer function to obtain an output signal.

[0120] In addition, an embodiment of the present invention further provides a computer-readable storage medium, which is applied to a computer. The computer-readable storage medium may be a non-volatile computer-readable storage medium. A sound field extension program is stored on the computer-readable storage medium. When the sound field extension program is executed by a processor, the steps of the sound field extension method of the present invention as described above are implemented.

[0121] For each embodiment of the audio device and the computer-readable storage medium of the present invention, reference may be made to each embodiment of the sound field extension method of the present invention, which will not be elaborated herein.

[0122] It should be noted that in this article, the term "comprising", "including" or any other variant thereof is intended to cover a non-exclusive inclusion, so that a process, method, article or system including a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or system. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or system including that element.

[0123] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages and disadvantages of the embodiments.

[0124] Through the description of the above embodiments, those skilled in the art can clearly understand that the above embodiment methods can be implemented by means of software plus a necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. The computer software product is stored in a storage medium as described above (such as ROM / RAM, magnetic disk, optical disc), and includes several instructions for causing a terminal device (which may be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0125] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present invention.

Claims

1. An acoustic field expansion method, characterized in that, The sound field expansion method includes the following steps: Obtain the artificial head transfer function, including: when the speaker of the near-ear open audio device is placed at the expansion target position and the speaker outputs a sound signal, measure the artificial head transfer function through a preset microphone in the preset ear canal of the artificial head; Obtain the free field transfer function; Perform an inverse operation on the free field transfer function to obtain the free field inverse transfer function; Multiply the artificial head transfer function by the free field inverse transfer function to obtain the target transfer function between the speaker at the expansion target position and the user's binaural ears; Perform sound field expansion processing on the input signal received by the near-ear open audio device according to the target transfer function to obtain an output signal; Play the output signal through the near-ear open audio device so that the binaural ears of the user wearing the near-ear open audio device receive the sound signal from the expansion target position.

2. The sound field expansion method according to claim 1, characterized in that The step of obtaining the free field transfer function includes: When the artificial head is removed and the speaker outputs a sound signal, measure the free field transfer function through preset microphones placed at the left and right ear positions before the artificial head is removed.

3. The sound field expansion method according to claim 1 or 2, characterized in that The step of performing sound field expansion processing on the input signal received by the near-ear open audio device according to the target transfer function to obtain an output signal includes: Multiply the input signal received by the near-ear open audio device by the target transfer function to obtain an output signal.

4. The sound field expansion method according to claim 1 or 2, characterized in that, The step of performing sound field expansion processing on the input signal received by the near-ear open audio device according to the target transfer function to obtain an output signal further includes: Perform reduced-order fitting on the target transfer function to obtain a low-order fitting transfer function; Multiply the input signal received by the near-ear open audio device by the low-order fitting transfer function to obtain an output signal.

5. An acoustic field expansion device, characterized in that, The sound field expansion device includes: An acquisition module, where the acquisition module is used to obtain the artificial head transfer function, including: when the speaker of the near-ear open audio device is placed at the expansion target position and the speaker outputs a sound signal, measure the artificial head transfer function through a preset microphone in the preset ear canal of the artificial head; The acquisition module is further used to obtain the free field transfer function; The acquisition module is further used to perform an inverse operation on the free field transfer function to obtain the free field inverse transfer function; multiply the artificial head transfer function by the free field inverse transfer function to obtain the target transfer function between the speaker at the expansion target position and the user's binaural ears; A processing module, where the processing module is used to perform sound field expansion processing on the input signal received by the near-ear open audio device according to the target transfer function to obtain an output signal; A playback module, where the playback module is used to play the output signal through the near-ear open audio device so that the binaural ears of the user wearing the near-ear open audio device receive the sound signal from the expansion target position.

6. An audio device, characterized in that, The audio device includes: a memory, a processor, and a sound field expansion program stored on the memory and executable on the processor. When the sound field expansion program is executed by the processor, the steps of the sound field expansion method according to any one of claims 1 to 4 are implemented.

7. A computer-readable storage medium, characterized in that, A sound field expansion program is stored on the computer-readable storage medium. When the sound field expansion program is executed by a processor, the steps of the sound field expansion method according to any one of claims 1 to 4 are implemented.

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