Spatial sound image correction in vehicle

Abstract

In general, a system and method for correcting audio spatial images within a vehicle is disclosed herein. Gains and delays of sound sources, such as loudspeakers in a vehicle, are adjusted such that the sound sources arrive at the listener simultaneously and at the same amplitude. A pair of symmetric output channels may be identified from a sound source, and a power spectrum difference between the pair of symmetric output channels may be calculated. A power spectrum equalization transfer function may be obtained and applied to each output channel pair. A center image of the sound source may be detected and adjusted by applying an additional amplitude or phase shift so that the center image may be placed in a desired position.

Description

Background Art

[0001] The automotive acoustic environment is significantly different from other types of enclosed spaces for audio playback. For example, the speakers in a vehicle are not symmetrically positioned relative to the driver in the driver's seat or the passenger in the passenger seat. Listeners in the driver's or passenger seats are usually fixed to their respective seats, so they are not positioned at the symmetrical center of the entire vehicle speaker system. Also, because the distance between the left and right speakers and the driver is different from the distance between the left and right speakers and the passenger, the sound image may be biased to one side, causing the driver and passenger to experience sound image localization errors or ambiguity.

[0002] Certain techniques have been developed to adjust the amplitude and time delay of a speaker system to correct the sound image to the desired or intended position of the user. However, adjusting the amplitude and time delay alone cannot resolve the spectral imbalance between the side output channels. Atypical direct or reflected path energy ratios in a vehicle can cause spectral imbalance. In addition, differences in head-related transfer functions (HRTFs) due to asymmetric speaker positions can also contribute to spectral imbalance. Summary of the invention

[0003] In general, a mechanism for correcting an audio spatial image within a vehicle is disclosed herein. Gains and delays of sound sources, such as speakers within a vehicle, are adjusted so that the sound sources arrive at a listener at the same time and with the same amplitude. Symmetrical output channel pairs relative to a center of the vehicle can be identified from the speakers in the vehicle, and power spectral differences between the symmetric output channel pairs can be calculated. A power spectral equalization transfer function can be obtained and applied to each output channel pair. A center sound image can be detected or obtained from an audio input signal, and the center sound image position can be adjusted by applying additional amplitude or phase shifts so that the center image can be placed at a desired location.

[0004] One aspect of the present disclosure provides a method for performing spatial sound image correction in a vehicle. The method includes detecting amplitude and time delay of two or more speakers, each speaker playing back one or more output channels; aligning the amplitude and time delay of the two or more speakers; capturing the spectrum of each output channel of the two or more speakers, wherein each output channel of a first speaker has a symmetrical output channel, which is one of the one or more output channels of a second speaker; analyzing the power spectrum difference between each output channel of the first speaker and each symmetrical output channel of the second speaker; calculating a power spectrum equalizer transfer function for each symmetrical output channel pair; and applying the power spectrum equalizer transfer function to each output channel of the two or more speakers.

[0005] In another example, the method further includes detecting a central sound image based on sound sources from the two or more speakers; and applying an additional amplitude panning to the central sound image to localize the central sound image to a desired location of the user.

[0006] Another aspect of the present disclosure provides a system for performing spatial image correction in a vehicle. The system includes a memory and one or more processors that communicate with the memory and are configured to receive detected amplitudes and time delays of two or more speakers, each speaker playing back one or more output channels; receive a captured spectrum of each output channel of the two or more speakers, wherein each output channel of a first speaker has a symmetrical output channel, which is one of the one or more output channels of a second speaker; receive an analyzed power spectrum difference between each output channel of the first speaker and each symmetrical output channel of the second speaker; receive a power spectrum equalizer transfer function calculated for each symmetrical output channel pair; align the amplitudes and time delays of the two or more speakers; receive a power spectrum equalizer transfer function for each symmetrical output pair; and apply the power spectrum equalizer transfer function to each output channel of the two or more speakers in the vehicle, the power spectrum equalizer transfer function being derived by a process comprising the following operations: capturing a spectrum of each output channel of the two or more speakers, wherein each output channel of the first speaker has a symmetrical output channel, which is one of the one or more output channels of the second speaker; analyzing the power spectrum difference between each output channel of the first speaker and each symmetrical output channel of the second speaker; and calculating the power spectrum equalizer transfer function for each symmetrical output channel pair.

[0007] In another example, the one or more processors are further configured to detect a central sound image based on sound sources from the two or more speakers; and apply additional amplitude panning to the central sound image to localize the central sound image to a desired location of the user.

[0008] Another aspect of the present disclosure provides a non-transitory machine-readable medium including machine-readable instructions encoded thereon for performing a spatial sound image correction method. The method includes detecting amplitudes and time delays of two or more speakers, each speaker playing back one or more output channels; aligning the amplitudes and time delays of the two or more speakers; capturing the spectrum of each output channel of the two or more speakers, wherein each output channel of the first speaker has a symmetrical output channel, which is one of the one or more output channels of the second speaker; analyzing the power spectrum difference between each output channel of the first speaker and each symmetrical output channel of the second speaker; calculating a power spectrum equalizer transfer function for each symmetrical output channel pair; and applying the power spectrum equalizer transfer function to each output channel of the two or more speakers.

[0009] The above and other aspects of the present disclosure may include one or more of the following features. In some examples, aspects of the present disclosure provide all of the following features in combination.

[0010] In another example, a power spectral equalizer transfer function is calculated using pre-measured frequency responses of each output channel of two or more loudspeakers.

[0011] In yet another example, the power spectrum equalizer transfer function is calculated using pre-measured head-related transfer function (HRTF) data based on the positions of two or more speakers in azimuth, elevation, or 3D coordinates.

[0012] In yet another example, a power spectrum equalizer transfer function is calculated using HRTF data modeled based on the positions of two or more speakers in azimuth, elevation, or 3D coordinates.

[0013] In yet another example, the power spectrum equalizer transfer functions are complementary for each symmetrical output channel.

[0014] In yet another example, a power spectrum equalizer transfer function is calculated based on head position and rotation information using one or more sensors.

[0015] In yet another example, the one or more sensors include one or more cameras equipped within the vehicle.

[0016] In yet another example, additional equalizer is used to make the center sound image clearer. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1A-1B Depicted is a block diagram illustrating a vehicle speaker system and artifact centering according to aspects of the present disclosure.

[0018] Figure 2A-2C Depicted is a block diagram illustrating psychoacoustic errors in left and right sound source perception in a vehicle in accordance with aspects of the present disclosure.

[0019] Figure 3A Depicted are graphs illustrating power spectra captured using left and right sides of a dummy head within a vehicle in accordance with aspects of the present disclosure.

[0020] Figure 3B Depicted are graphs illustrating power spectrum equalizer filter responses based on a power spectrum captured using a dummy head in accordance with aspects of the present disclosure.

[0021] Figure 4 Depicted is a flow chart illustrating an example power spectrum equalizer design method in accordance with aspects of the present disclosure.

[0022] Figure 5 Depicted is a block diagram illustrating an example power spectral equalization and gain / delay adjustment process for a stereo signal in accordance with aspects of the present disclosure.

[0023] Figure 6 Depicted is a block diagram illustrating an example center repositioning module for multiple input audio signals in accordance with aspects of the present disclosure.

[0024] Figure 7 Depicted is a block diagram illustrating example spatial image correction in a vehicle according to aspects of the present disclosure.

[0025] Figure 8 Depicted is a block diagram illustrating an example automotive aerial image correction system in accordance with aspects of the present disclosure. DETAILED DESCRIPTION

[0026] In general, a system and method for automatically correcting spectral imbalance between two or more speakers that output multiple lateral output channels in a vehicle is disclosed herein. The gain and delay of the sound output from the speakers can be aligned. Symmetrical output channel pairs can be identified from the speaker layout of the vehicle. For example, a first speaker can have a first channel output, and a second speaker can have a second channel output, wherein the first channel output and the second channel output are a laterally symmetrical pair. The power spectrum difference between the first output channel pair from the first speaker and the second output channel pair from the second speaker can be calculated. A power spectrum equalization transfer function can be obtained based on the power spectrum difference of the symmetrical output channel pair. The power spectrum equalization transfer function can be applied to the sound output channel. The sound image of the sound output can be further adjusted to the desired position of the user by adopting selective equalization and amplitude and / or time delay alignment.

[0027] Figure 1A-1BA block diagram illustrating a vehicle speaker system and artifact center positioning is depicted. The vehicle 100 may include an interior cabin equipped with a driver seat 120, a passenger seat 130, and a steering wheel 140. In this example, the driver seat 120 is located on the left side of the vehicle 100, while the passenger seat 130 is located on the right side. It should be understood that the above arrangement may be different in other vehicles.

[0028] Figure 1A The diagram illustrates the unequal distances between the left and right sound sources within the vehicle 100. The vehicle 100 may be equipped with four speakers: speakers 104-110. Speakers 104 and 108 are located on the left side of the vehicle, while speakers 106 and 110 are located on the right side of the vehicle. In this example, the user 102 is a driver sitting in a driver's seat 120. Since the user 102 is positioned toward the left side of the vehicle, the distance d_L1 between the speaker 104 and the user 102 is shorter than the distance d_R1 between the speaker 106 and the user 102. Similarly, the distance d_L2 between the speaker 108 and the user 102 is shorter than the distance d_R2 between the speaker 110 and the user 102.

[0029] refer to Figure 1B , due to the difference in distance between the left and right speakers and the user 102, a sound image can be formed biased to one side. The sound image can refer to the spatial position of the sound source perceived by the user. The position of the sound image can be ambiguous, for example, if the sound from both sides does not arrive at the user at the same time and the difference between the first arrival time when the sound from the left speaker arrives and the second arrival time when the sound from the right speaker arrives is greater than a certain time value. For example, when the difference between the above arrival times is greater than 3ms and less than 15ms, positioning ambiguity occurs. Due to the above difference, an artifact center 112 can be formed toward the left side of the user 102. The artifact center can refer to a psychoacoustic phenomenon in which a sound source seems to emanate from a point between at least two speakers. For the purposes of the present disclosure, psychoacoustics can refer to any type of scientific study of sound perception and audiology.

[0030] Gain and delay adjustments can correct or adjust the sound image to a desired or expected position. For example, if the gain of the right speaker 106 is increased to match the gain of the left speaker 104 and the delay of the left speaker 104 is matched to the delay of the right speaker 106, then the artifact center 112 can be moved to the right to be positioned in the middle of where the wheels are located. However, since the environment in the vehicle is a closed environment and each sound source can be reflected in various ways from the surfaces of various objects in the vehicle, adjusting the gain and delay of the direct sound source may not be sufficient to correct the sound localization error or ambiguity.

[0031] Figure 2AThe sound energy of direct sound and reflected sound measured using microphones is illustrated. Reflected sound can refer to the sound reflected from the surface of any object. In the example shown, six microphones are attached to the driver's seat, and one of the six microphones, i.e., microphone 200, can be used to measure the energy of the sound output from the right speaker 230. For example, two different sound energy measurements can be detected using microphone 200. Direct sound 204 and reflected sound 202 can be measured and compared. Reflected sound 202 can be reflected from the driver's side window. Since reflected sound 202 arrives later than direct sound 204, the energy (S1) of direct sound 204 can be lower than the energy (S2) of reflected sound 202. In other examples, different numbers of microphones can be used.

[0032] refer to Figure 2B , user 201 sits on driver's seat 222, and reflects sound 206 and direct sound 208 are measured. In this example, unlike conventional microphone measurements in which the arrangement of microphones does not have a head and torso, the head of user 201 attenuates direct sound 208 relative to the left ear of user 201. Since the right side of the head of user 201 can block the path of direct sound 208, the energy of direct sound 208 measured at the left ear of user 201 can be lower than the energy of reflected sound 206 measured at the left ear of user 201. In addition, the azimuth difference between the left and right speakers and user 201 can cause spectral imbalance between left and right sounds. Azimuth can refer to the angle between the sound or response position, the center of the head of user 201 and the middle plane in front of the head of user 201. Spectral imbalance can refer to the unbalanced distribution of sound energy between the left and right ears of the listener.

[0033] refer to Figure 2C , illustrating the timbre differences and sound image segmentation caused by the spectral differences. Timbre may refer to the perceived sound quality of a musical sound or tone. A head-related transfer function (HRTF) may vary due to different positions of the sound relative to the user 201. HRTF may refer to a transfer function that describes how a sound from a particular point reaches the ear of the user 201. Sounds 210 (HLL) and 212 (HLR) are output from the left speaker 220. Sounds 214 (HRL) and 216 (HRR) are output from the right speaker 230. Since the total energy of sounds 210 and 212 is not equal to the total energy of sounds 214 and 216, Figure 2C Amplitude and time delay alignment of the left and right speakers may not be sufficient to resolve perceived timbre differences and sound image segmentation.

[0034] According to some embodiments, power spectrum equalization (PSE) may be performed to compensate for the spectral difference between the left speaker 220 and the right speaker 230 described above. The HRTF may be measured using a dummy head or a human in a vehicle, or may be obtained using modeling (e.g., a spherical head model). In one example, the power sum of the ipsilateral and contralateral HRTFs as shown in the following equation may be used to correct Figure 2C The perceived timbre differences shown in .

[0035] Equation 1: Hpse_L = (|HRR| + |HRL|) / (|HLL| + |HLR|)

[0036] Equation 2: Hpse_R = (|HLL| + |HLR|) / (|HRR| + |HRL|)

[0037] Equations 1 and 2 may represent the power spectrum difference between the left sound and the right sound. According to some examples, only one of the above two equations may be applied to the right / left audio channel audio, since both equations 1 and 2 represent the entire spectrum difference.

[0038] According to some embodiments, an equalizer (EQ) may be applied to the right channel audio as represented in the following equation.

[0039] Equation 3: HLout = HLin * Z -m ,HRout=HRin*Hpse,Z represents the equalizer, and “m” may refer to the time delay in samples from the PSE filter.

[0040] According to some embodiments, a power preservation EQ may be used in place of the original EQ. If the original EQ is applied to a channel, energy may be subtracted from or added to different frequency bins, where the overall timbre is not preserved relative to the unequalized sound. The power preservation EQ is applied using the following equation.

[0041] Equation 4:

[0042] Equation 5:

[0043] Figure 3A A graph illustrating the power spectra of the left and right speakers is depicted. Graph line 302 represents the power spectrum of the left speaker, and graph line 204 represents the power spectrum of the right speaker. As shown in the graph, the difference between the power spectra of the left and right speakers is obvious.

[0044] Figure 3BDepicted are graphs illustrating power spectrum equalizer filter responses. Graph line 302 represents the power spectrum with EQ applied to the left speaker only. Graph line 304 represents the power spectrum with power-preserving EQ applied to the left speaker only. Graph line 306 represents the power spectrum with power-preserving EQ applied to the right speaker only. Because different combinations of filtering effects can be caused by various time delays caused by reflections of sound from the left and right speakers, the power spectrum equalizer can be smooth as shown in graphs 304 and 306. The PSEQ represented by graphs 302 or 308 cannot be applied at the same time. However, both power-preserving PSEQ 304 and 306 can be applied to the left and right speakers.

[0045] According to some embodiments, multiple microphone measurements can be used so that multiple measurements can average the sound power measured at various head positions of the listener. PSE can be measured and modeled in a similar manner so that multiple positions of the user's head can be averaged to minimize errors based on the position of the listener. In another example, various sensors (such as event cameras) can be used to capture head position and rotation information to apply PSE to the sound captured at a given head position to further optimize PSE.

[0046] Figure 4 A flow chart illustrating an example power spectrum equalizer design method is depicted. According to block 402, the amplitude and time delay of the sound from two or more speakers are measured. According to some embodiments, the automotive spatial image correction system may include two or more speakers equipped in the vehicle. The driver and the passenger may sit in a driver seat and a passenger seat, respectively. The position of the driver seat or the passenger seat cannot be adjusted laterally. The distance between the left speaker and the driver or the passenger may be different from the distance between the right speaker and the driver or the passenger.

[0047] According to block 404, the amplitude and time delay of the sounds from the two or more speakers may be aligned. Since the distance between the left speaker and the driver / passenger is different from the distance between the right speaker and the driver / passenger, the sound from the left speaker does not reach the driver / passenger's ears at the same time as the sound from the right speaker.

[0048] According to block 406, the spectrum of each output channel from two or more speakers is captured. Each speaker can output one or more different sound channels. For example, the left front channel (input signal) can be played back by (one or more) left door speakers and (one or more) left rear door speakers. Rear seat passengers may need to hear the front sound. At the same time, (one or more) left rear door speakers can also play the left sound channel (input).

[0049] According to block 408, the power spectrum differences of each symmetrical sound channel pair are analyzed. For example, direct sound from the left speaker reaches both ears of the listener; one is directed to the right ear of the driver / passenger, and the other is directed to the left ear of the driver / passenger. The right speaker also outputs sound directed to each ear of the driver / passenger. The sum of the power spectra can be identified by grouping the sound directed to each ear of the driver / passenger from the left speaker with the sound directed to each ear of the driver / passenger from the right speaker, and vice versa.

[0050] According to block 410, a power spectrum equalizer transfer function is designed for each symmetrical output channel pair. According to some embodiments, power spectrum equalization (PSE) may be performed using the HRTF data to calculate the equalization transfer function. In an example, the sum of the power of the sound channels on one side of the speaker is divided by the sum of the power of the sound channels on the other side of the speaker. According to some embodiments, a power-preserving EQ may be applied by taking the square root of the PSE mentioned above for one of the sound channels.

[0051] Figure 5 A block diagram illustrating an example power spectrum equalization and gain / delay adjustment process for a stereo signal is depicted. According to some embodiments, the spatial image correction process can be a cascaded process of PSE with amplitude and time delay alignment. Since they are all linear time-invariant (LTI) processes, the results can be the same even if the processing order changes. For example, an automotive spatial image correction system can include right and left speakers. The left speaker can include a left channel audio signal input 502, a left channel PSE 504, a left channel delay line 506-512, a left channel gain line 514-520, and a left channel output 522-526. The right speaker can include a right channel audio signal input 532, a right channel PSE 534, a right channel delay line 536-542, a right channel gain line 544-550, and a right channel output 552-556. The right and left channel audio signal inputs can be divided into multiple sound channels. Each sound channel can correspond to one of the different sound components. The gain and time delay of each channel can be adjusted separately. For example, each of the delay lines 506-512 and 536-542 can adjust the time delay of each sound channel. Similarly, the gain of each sound channel can be adjusted separately. Gain lines 514-520 and 544 and 550 can adjust the gain of each sound channel.

[0052] According to some embodiments, the right and left PSE may be applied to each of the left or right sound channel outputs 522-526 and 552-556, or to the left and right audio signal inputs 502 and 532 before each channel is assigned to each delay and gain line. The power spectrum equalization process shown is a linear time-invariant process, so even if the order of processing is changed, the results are exactly the same.

[0053] Figure 6 A block diagram illustrating an example center repositioning module 600 for multiple input audio signals is depicted. According to some embodiments, PSE and amplitude and time delay alignment may allow for adjustment of the center image position in a vehicle. Even if there is a center speaker in the vehicle, the center image may not be effectively adjusted by utilizing amplitude panning methods alone due to the asymmetric speaker location and the unbalanced spectrum of left and right sounds perceived by the driver / passenger. By applying source panning in combination with PSE and amplitude and time delay alignment, the center sound image may be modified to be located at the driver / passenger's preferred position.

[0054] The center repositioning module may include a 5.1 surround sound system. The 5.1 surround sound system may include five sound channels: a left sound channel 602, a center sound channel 604, a right sound channel 606, a left surround sound channel 608, and a right surround sound channel 610. The center repositioning module 600 may receive a driver / passenger's desired center image position 612 via a graphical user interface on an electronic device (such as a smart watch, smart phone, or tablet) that is communicable with the vehicle's stereo system. Once the center repositioning module 600 receives the user's desired center image position 612, the center image may be repositioned using amplitude / phase shifting and power normalization. Once the center image is repositioned to the center repositioning 614, the center repositioning may be divided into center-left, center-center, center-right, center-left surround, and center-right surround channels and distributed to a gain and delay alignment unit 616. The gain and delay alignment unit 616 may perform gain and delay alignment and apply PSE to each sound channel before sending the modified sound channels to speakers 618-624. The gain and delay alignment unit 616 may receive not only the center repositioned channel, but also the original and unmodified sound channels, such as the left sound channel 602 , the right sound channel 606 , the left surround sound channel 608 , and the right surround sound channel 610 .

[0055] According to some embodiments, the center image may be repositioned using additional power normalization applied to conventional audio source panning. Audio source panning may refer to the distribution of sound across a stereo or surround sound spectrum to create a balanced sound. Since the panned center image may reside in a stereo mix along with the original panning, the gain from the original panning must be removed before repositioning the center image. For example, the panned center output level may be 3dB lower than the output level of the original signal because even though the center sound source in the left and right sound channel levels was already reduced by 3dB during the original mixing stage, the original panning may further reduce it by 3dB. The normalization process may be performed using the following equation.

[0056] Equation 6: L_c = cos(45)*C and R_c = sin(45)*C

[0057] The above equation provides the panned center of the artifact by setting the original adjusted center position to 0 degrees. The re-panned left and right sound channels can be expressed as follows:

[0058] Equation 7: L_c' = norm_coeff*cos(45+alpha)*L_c, where alpha is the angle from the center position of the speaker, and its range is = / -45 degrees.

[0059] Equation 8: R_c' = norm_coeff*sin(45+alpha)*R_c

[0060] If alpha is 0 degrees, then norm_coeff becomes 1 / cos(45) or 1 / sin(45).

[0061] Figure 7 A block diagram of an example spatial image correction in an illustrated vehicle is depicted. User 702 is a driver sitting in driver's seat 701. Vehicle 700 is equipped with a left speaker 704 and a right speaker 706. Without amplitude and delay alignment, center image 714 is located on the left side of the vehicle near left speaker 704. If the automotive spatial image correction system aligns the amplitude, time delay, and power spectrum equalization of the sound from left speaker 704 and right speaker 706, then center image 714 can be moved to a position that forms an adjusted center image 710. Figure 6 As shown in , the center repositioning module 600 can receive the user's desired center image information and reposition the center image 710 to the repositioned center image 712 based on the amplitude / phase shift and power normalization of the sound.

[0062] Figure 8 A block diagram of an example automotive spatial image correction system is depicted. A user computing device 812 and a server computing device 815 may be communicatively coupled to one or more storage devices 830 via a network 860. The storage device(s) 830 may be a combination of volatile and non-volatile memory and may be located at the same or different physical location as the computing devices 812, 815. For example, the storage device(s) 830 may include any type of non-transitory computer-readable medium capable of storing information, such as a hard drive, a solid-state drive, a tape drive, an optical storage device, a memory card, a ROM, a RAM, a DVD, a CD-ROM, a writable memory, and a read-only memory. The user computing device 812 may be attached to a vehicle and may communicate with the vehicle's stereo system to control output sound channels from two or more speakers in the vehicle.

[0063] The server computing device 815 may include one or more processors 813 and memory 814. The memory 814 may store information accessible to the processor(s) 813, including instructions 821 that the processor(s) 813 may execute. The memory 814 may also include data 823 that the processor(s) 813 may retrieve, manipulate, or store. The memory 814 may be a type of non-transitory computer-readable medium capable of storing information accessible to the processor(s) 813, such as volatile and non-volatile memory. The processor(s) 813 may include one or more central processing units (CPUs), graphics processing units (GPUs), field programmable gate arrays (FPGAs), and / or application specific integrated circuits (ASICs), such as tensor processing units (TPUs).

[0064] Instructions 821 may include one or more instructions that, when executed by (one or more) processors 813, cause the one or more processors to perform actions defined by the instructions. Instructions 821 may be stored in an object code format so that they are directly processed by (one or more) processors 813, or in other formats, including a collection of interpretable scripts or independent source code modules that are interpreted or compiled in advance as needed. Instructions 821 may include instructions for implementing processing consistent with aspects of the present disclosure. Such processing may be performed using (one or more) processors 813 and / or using other processors placed away from the server computing device 815.

[0065] Data 823 can be retrieved, stored, or modified by (one or more) processors 813 according to instructions 821. Data 823 can be stored in computer registers, relational or non-relational databases, as tables with multiple different fields and records, or as JSON, YAML, proto, or XML documents. Data 823 can also be formatted in a computer readable format, such as but not limited to binary values, ASCII, or Unicode. In addition, data 823 can include information sufficient to identify relevant information, such as numbers, descriptive text, proprietary codes, pointers, references to data stored in other memories (including other network locations), or information that functions are used to calculate relevant data.

[0066] The user computing device 812 may also be configured similarly to the server computing device 815, with one or more processors 816, memory 817, instructions 818, and data 819. The user computing device 812 may also include a user output 826 and a user input 824. The user input 824 may include any suitable mechanism or technology for receiving input from a user, such as a keyboard, a mouse, a mechanical actuator, a soft actuator, a touch screen, and a microphone. The user computing device 812 may send the user's preferred position for the sound image via a graphical user interface on a display.

[0067] The server computing device 815 may be configured to transmit data to the user computing device 812, and the user computing device 812 may be configured to display at least a portion of the received data on a display implemented as part of the user output terminal 826. The user output terminal 826 may also be used to display the interface between the user computing device 812 and the server computing device 815. For example, if the user computing device 812 sends the user's preferred location information to the server computing device 815, the server computing device 813 sends information about the appropriate gain and delay levels of each of the two or more output channels of the speaker. Once the user computing device 812 receives the information from the server computing device 815, the user computing device 812 can adjust or modify the gain and delay levels of one or more sound output channels to adjust the position of the sound image. In some examples, the user output terminal 826 may alternatively or additionally include one or more speakers, transducers or other audio output terminals, tactile interfaces, or other tactile feedback that provides non-visual and non-auditory information to the platform user of the user computing device 812.

[0068] Although Figure 8 The processors 813, 816 and memories 814, 817 are illustrated as being located within computing devices 815, 812, but the components described in this specification (including processors 813, 816 and memories 814, 817) may include multiple processors and memories that may operate at different physical locations rather than within the same computing device. For example, some of instructions 821, 818 and data 823 and 819 may be stored on a removable SD card, and other instructions and data may be stored within a read-only computer chip. Some or all of the instructions and data may be stored in a location physically away from the processors 813, 816 but still accessible thereto. Similarly, processors 813 and 816 may include a collection of processors that may perform concurrent and / or sequential operations. Computing devices 815 and 812 may each include one or more internal clocks that provide timing information, which may be used for time measurement of operations and programs run by computing devices 815 and 812.

[0069] Devices 812 and 815 may be able to communicate directly and indirectly through network 860. Devices 812 and 815 may be provided with listening sockets that may accept initiated connections for sending and receiving information. Network 860 itself may include various configurations and protocols, including the Internet, the World Wide Web, an intranet, a virtual private network, a wide area network, a local network, and a private network using one or more company-specific communication protocols. Network 860 may support various short-range and long-range connections. Additionally or alternatively, network 860 may also support wired connections between devices 812 and 815, including through various types of Ethernet connections.

[0070] Although Figure 8 A single server computing device 815 and user computing device 812 are shown in FIG, but it should be understood that aspects of the present disclosure can be implemented in accordance with a variety of different computing device configurations and quantities, including in a paradigm for sequential or parallel processing, or on a distributed network of multiple devices. In some implementations, aspects of the present disclosure can be performed on a single device, as well as on any combination thereof.

[0071] Aspects of the present disclosure may be implemented in digital circuits, computer-readable storage media, as one or more computer programs, or a combination of one or more of the above. The computer-readable storage medium may be non-transitory, for example, as one or more instructions executable by a cloud computing platform and stored on a tangible storage device.

[0072] In this specification, the phrase "configured to" is used in different contexts related to a computer system, hardware, or part of a computer program, engine, or module. When a system is referred to as being configured to perform one or more operations, it means that the system has appropriate software, firmware, and / or hardware installed on the system, which, when in operation, causes the system to perform one or more operations. When certain hardware is referred to as being configured to perform one or more operations, it means that the hardware includes one or more circuits, which, when in operation, receive inputs and generate outputs corresponding to the one or more operations based on the inputs. When a computer program, engine, or module is referred to as being configured to perform one or more operations, it means that the computer program includes one or more program instructions, which, when executed by one or more computers, cause the one or more computers to perform one or more operations.

[0073] Although the present technology has been described herein with reference to specific examples, it should be understood that these examples are only used to illustrate the principles and applications of the present technology. Therefore, it should be understood that various modifications can be made and other arrangements can be designed without departing from the spirit and scope of the present technology as defined by the appended claims.

[0074] Unless otherwise stated, the above alternative examples are not mutually exclusive, but can be implemented in various combinations to achieve unique advantages. Since these and other variations and combinations of the above features can be utilized without departing from the subject matter defined by the claims, the above description should be taken as an illustration, not as a limitation on the subject matter defined by the claims. In addition, the provision of examples described herein and the terms "such as", "including", etc. should not be interpreted as limiting the subject matter of the claims to specific examples; on the contrary, these examples are intended to illustrate only one of many possible implementations. In addition, the same reference numbers in different figures may identify the same or similar elements.

Claims

1. A method for performing spatial sound image correction in a vehicle, the method comprising: detecting amplitude and time delay of two or more loudspeakers, each of which plays back one or more output channels; aligning amplitudes and time delays of the two or more speakers; capturing a frequency spectrum of each output channel of the two or more speakers, wherein each output channel of a first speaker has a symmetrical output channel that is one of the one or more output channels of a second speaker; analyzing a difference in power spectra between each output channel of the first loudspeaker and each symmetrical output channel of the second loudspeaker; calculating a power spectrum equalizer transfer function for each symmetrical output channel pair; as well as A power spectral equalizer transfer function is applied to each output channel of the two or more loudspeakers.

2. The method of claim 1, wherein the power spectral equalizer transfer function is calculated using pre-measured frequency responses of each output channel of the two or more loudspeakers.

3. The method of claim 1, wherein the power spectrum equalizer transfer function is calculated using head-related transfer function (HRTF) data pre-measured based on the positions in azimuth, elevation, or 3D coordinates of the two or more speakers. 4 . The method of claim 1 , wherein the power spectrum equalizer transfer function is calculated using HRTF data modeled based on the positions of the two or more speakers in azimuth, elevation, or 3D coordinates.

5. The method of claim 1, wherein the power spectrum equalizer transfer function is complementary for each symmetrical output channel pair.

6. The method of claim 1, wherein the power spectrum equalizer transfer function is calculated based on head position and rotation information using one or more sensors.

7. The method of claim 6, wherein the one or more sensors include one or more cameras equipped in the vehicle.

8. The method of claim 1, further comprising: detecting a central sound image based on sound sources from the two or more speakers; as well as An additional amplitude shift is applied to the central sound image to position the central sound image to the user's desired location.

9. The method of claim 8, wherein an additional equalizer is used to make the central sound image clearer.

10. A system for performing spatial sound image correction in a vehicle, the system comprising: Memory; as well as one or more processors in communication with the memory and configured to: receiving detected amplitudes and time delays of two or more speakers, each speaker playing back one or more output channels; receiving a captured spectrum for each output channel of the two or more speakers, wherein each output channel of a first speaker has a symmetrical output channel that is one of the one or more output channels of a second speaker; receiving an analyzed power spectrum difference between each output channel of the first speaker and each symmetrical output channel of the second speaker; receiving a power spectrum equalizer transfer function calculated for each symmetrical output channel pair; aligning amplitudes and time delays of the two or more speakers; receiving a power spectrum equalizer transfer function for each symmetrical output pair; as well as Applying a power spectral equalizer transfer function to each output channel of the two or more speakers in the vehicle, the power spectral equalizer transfer function being derived by a process comprising the following operations: capturing a frequency spectrum of each output channel of the two or more speakers, wherein each output channel of a first speaker has a symmetrical output channel that is one of the one or more output channels of a second speaker; analyzing a difference in power spectra between each output channel of the first loudspeaker and each symmetrical output channel of the second loudspeaker; as well as The power spectrum equalizer transfer function is calculated for each symmetrical output channel pair.

11. The system of claim 10, wherein the power spectrum equalizer transfer function is calculated using pre-measured frequency responses of each output channel of the two or more speakers.

12. The system of claim 10, wherein the power spectrum equalizer transfer function is calculated using pre-measured head-related transfer function (HRTF) data based on the positions of the two or more speakers in azimuth, elevation, or 3D coordinates.

13. The system of claim 10, wherein the power spectrum equalizer transfer function is calculated using HRTF data modeled based on the positions of the two or more speakers in azimuth, elevation, or 3D coordinates.

14. The system of claim 10, wherein the power spectrum equalizer transfer function is complementary for each symmetrical output channel.

15. The system of claim 10, wherein the power spectrum equalizer transfer function is calculated based on head position and rotation information using one or more sensors.

16. The system of claim 15, wherein the one or more sensors include one or more cameras equipped in the vehicle.

17. The system of claim 10, wherein the one or more processors are further configured to: detecting a central sound image based on sound sources from the two or more speakers; and An additional amplitude shift is applied to the central sound image to position the central sound image to the user's desired location.

18. The system of claim 17, wherein an additional equalizer is used to sharpen the central sound image.

19. A non-transitory machine-readable medium comprising machine-readable instructions encoded thereon for performing a spatial sound image correction method, the method comprising: detecting amplitude and time delay of two or more loudspeakers, each of which plays back one or more output channels; aligning amplitudes and time delays of the two or more speakers; capturing a frequency spectrum of each output channel of the two or more speakers, wherein each output channel of a first speaker has a symmetrical output channel that is one of the one or more output channels of a second speaker; analyzing a difference in power spectra between each output channel of the first loudspeaker and each symmetrical output channel of the second loudspeaker; calculating a power spectrum equalizer transfer function for each symmetrical output channel pair; as well as A power spectral equalizer transfer function is applied to each output channel of the two or more loudspeakers.

20. The non-transitory machine-readable medium of claim 19, wherein the power spectrum equalizer transfer function is calculated using HRTF data modeled based on the positions of the two or more speakers in azimuth, elevation, or 3D coordinates.

Images