A headrest-speaker-based in-vehicle spatial audio output method, device, equipment and medium

Abstract

The application discloses a headrest loudspeaker-based in-vehicle spatial audio output method and device, equipment and medium, and relates to the technical field of computers. The method comprises the following steps: acquiring in-vehicle loudspeaker layout information; determining the relative spatial position relationship between the seat where the headrest loudspeaker is located and the surround, rear surround and rear sky channel loudspeakers according to the layout information, and calculating the spatial compensation parameters of the to-be-compensated channels accordingly; determining the current rendering mode in the full-vehicle mode and the headrest mode based on in-vehicle passenger information; generating the audio signal of the headrest loudspeaker by using the spatial compensation parameters according to the processing mode corresponding to the mode, rendering the to-be-rendered spatial audio signal to obtain a multi-channel loudspeaker rendering signal, and synchronously outputting the two signals. Thus, the adverse effects of the seat backrest on the rear channels can be overcome, and the spatial atmosphere and sound source orientation of the in-vehicle spatial audio can be restored.

Description

Technical Field

[0001] This invention relates to the field of computer technology, and in particular to a method, apparatus, device, and medium for in-vehicle spatial audio output based on headrest speakers. Background Technology

[0002] With the advancement of automotive intelligence and the continuous upgrading of the cabin experience, in-vehicle audio systems are evolving from traditional stereo playback to multi-channel spatial audio. Immersive audio formats, represented by object-oriented audio, divide audio content into bed signals and object signals, and use rendering algorithms such as Vector Base Amplitude Panning (VBAP) and Head-Related Transfer Function (HRTF) to map the sound source into the three-dimensional space surrounding the listener. To support this, mainstream high-end models are now equipped with multi-channel speaker systems. Common layouts include 5.1 (front left FL, front right FR, center C, left surround SL, right surround SR, low-frequency effect LFE), 5.1.4, 7.1, and 7.1.4, with each speaker arranged according to the vehicle's acoustic design in locations such as the dashboard, doors, rear window sill, and roof, achieving basic spatial audio rendering effects. At the same time, more and more high-end models are starting to integrate speakers (i.e., headrest speakers) into the seat headrests. Some models are equipped only in the driver's seat, while others are also equipped in the passenger seat and other seats. Each set of headrest speakers usually contains two independent channel speaker units, distributed on both sides of the occupant's head, very close to the occupant's ears.

[0003] See Figure 1 As shown, Figure 1 This diagram illustrates a typical in-vehicle speaker layout and addresses seat obstruction issues. Taking layout 7.1.4 as an example, the left front channel speaker FL, right front channel speaker FR, and center channel speaker C are located on the dashboard at the front of the passenger compartment. The left surround channel speaker SL and right surround channel speaker SR are located on either side of the passenger compartment. The left rear surround channel speaker RL and right rear surround channel speaker RR are located on either side of the rear of the passenger compartment. The left front sky channel speaker TFL, right front sky channel speaker TFR, left rear sky channel speaker TRL, and right rear sky channel speaker TRR are located at the front and rear of the roof. These speakers together constitute a multi-channel speaker system in the vehicle. Furthermore, the headrests of the driver's and passenger's seats can each integrate headrest speakers with two independent left and right channels, respectively. Figure 1As shown in the sound wave propagation path diagram, for occupants in the driver's seat and front passenger seat, the surround sound speakers, rear surround sound speakers, and rear sky sound speakers are all located to their sides or above. The sound waves of the corresponding channels must pass through the area where the seat back and headrest are located before reaching the occupants' ears, thus inevitably being blocked by the seat back and headrest. However, the headrest speakers integrated into the headrest are located outside the blockage, and their sound waves can reach the occupants' ears directly.

[0004] However, due to the confined and heavily obstructed listening environment inside a vehicle, the aforementioned technologies still have significant shortcomings in practical applications. For vehicles without headrest speakers, this obstruction causes significant energy attenuation and mid-to-high frequency loss in the surround sound channels, rear surround sound channels, and rear ceiling sound channels. This significantly weakens the sense of spatial atmosphere and blurs or even shifts the location of rear-facing sound sources, making it difficult to form a complete and continuous surround sound field. Even in vehicles equipped with headrest speakers, in existing solutions, these speakers are typically used as independent channels for personalized audio content such as navigation prompts and phone calls. They operate independently from other speakers in the vehicle, neither integrated into a unified spatial audio rendering system nor effectively compensating for the obstructed surround sound channels. Furthermore, most existing spatial audio rendering algorithms are designed for individual conventional speaker layouts or individual near-field headrest speakers. The differences in gain, delay, frequency response, and phase between the two types of speakers, as well as their relative spatial positions, are not taken into account in a unified manner. When both speakers emit sound simultaneously, problems such as sound image splitting, positioning shift, and timbre coloration are likely to occur, making it difficult to fully realize the enhancement potential of headrest speakers in spatial audio. At the same time, the rendering strategies of existing solutions are relatively fixed and lack flexible switching mechanisms for different usage scenarios such as multi-person listening throughout the vehicle and single-person exclusive listening, making it difficult to achieve a balance between taking into account the listening experience of each seat and maximizing the immersive experience of a single seat.

[0005] As can be seen from the above, overcoming the adverse effects of seat backrests obstructing the rear audio channels and restoring the spatial atmosphere and sound source location of the in-car audio is an urgent problem to be solved. Summary of the Invention

[0006] In view of this, the purpose of this invention is to provide a method, apparatus, device, and medium for in-vehicle spatial audio output based on headrest speakers, which can overcome the adverse effects of seat backrest obstruction on the rear sound channel and restore the spatial atmosphere and sound source location of the in-vehicle audio. The specific solution is as follows: In a first aspect, this application provides a method for in-vehicle spatial audio output based on headrest speakers, including: Obtain in-vehicle speaker layout information; the in-vehicle speaker layout information includes the position information of each channel speaker in the in-vehicle multi-channel speaker system and the position information of the headrest speakers; the in-vehicle multi-channel speaker system includes multiple front channel speakers, center channel speakers, front overhead channel speakers, surround channel speakers, rear surround channel speakers and rear overhead channel speakers respectively set in different positions in the vehicle; the headrest speakers are speaker groups integrated into the seat headrests and containing two independent channels distributed on both sides of the occupant's head; The relative spatial relationship between the headrest speaker's location and the surround sound speakers, the rear surround sound speakers, and the rear sky sound speakers is determined based on the in-vehicle speaker layout information. Spatial compensation parameters from the channel to be compensated to the headrest speaker's location are then calculated based on this relative spatial relationship. The channel to be compensated includes the surround sound channel, the rear surround sound channel, and the rear sky sound channel. The spatial compensation parameters include gain parameters, delay parameters, equalization parameters, and all-pass filter parameters. Obtain information about the occupants inside the vehicle, and determine the current rendering mode in both the full vehicle mode and the headrest mode based on the occupant information. According to the processing method corresponding to the current rendering mode, the channel signal corresponding to the channel to be compensated in the spatial audio signal to be rendered is processed using the spatial compensation parameters to generate the audio signal of the headrest speaker, and spatial audio rendering is performed on the spatial audio signal to be rendered to obtain the multi-channel speaker rendering signal corresponding to the in-vehicle multi-channel speaker system. The audio signal from the headrest speaker is output synchronously with the rendering signal from the multi-channel speaker to compensate for the sound attenuation of the channel to be compensated caused by the obstruction of the seat back.

[0007] Optionally, calculating the spatial compensation parameters from the channel to be compensated to the seat where the headrest speaker is located based on the relative spatial position relationship includes: The gain parameter is calculated based on the distance from the seat where the headrest speaker is located to the surround channel speaker, the rear surround channel speaker, and the rear sky channel speaker, as well as the degree of obstruction of the channel to be compensated by the seat back. The delay parameter is calculated based on the difference in sound wave propagation path from the channel to be compensated to the seat where the headrest speaker is located, so as to align the time difference between the headrest speaker and the surround channel speaker, the rear surround channel speaker and the rear sky channel speaker reaching the occupant's ear. The equalization parameters are calculated based on the absorption and reflection characteristics of the seat back at different frequency bands to compensate for the frequency response distortion caused by the obstruction of the seat back. The all-pass filter parameters are calculated based on the phase distortion caused by multipath reflections and seat back obstruction, so as to adjust the phase response of the channel to be compensated without changing the amplitude response.

[0008] Optionally, determining the current rendering mode includes: Occupant information is acquired through preset occupant detection sensors; the preset occupant detection sensors include seat pressure sensors and / or cameras. If the occupant information indicates that there are occupants in multiple seats inside the vehicle, then the full vehicle mode is determined as the current rendering mode. If the occupant information indicates that there is an occupant only in the driver's seat or only in the front passenger seat, then the headrest mode is determined as the current rendering mode, and the driver's seat or front passenger seat with an occupant is determined as the seat where the headrest speaker is located. If a mode selection instruction is received from the user, the rendering mode corresponding to the mode selection instruction will be determined as the current rendering mode.

[0009] Optionally, the step of processing the channel signal corresponding to the channel to be compensated in the spatial audio signal to be rendered using the spatial compensation parameters according to the processing method corresponding to the current rendering mode, to generate the audio signal of the headrest speaker, and performing spatial audio rendering on the spatial audio signal to be rendered to obtain the multi-channel speaker rendering signal corresponding to the in-vehicle multi-channel speaker system, includes: If the current rendering mode is full vehicle mode, then a preset speaker rendering algorithm is used to perform spatial audio rendering on the spatial audio signal to be rendered, so as to obtain a multi-channel speaker rendering signal corresponding to the in-vehicle multi-channel speaker system; the preset speaker rendering algorithm includes a vector basis amplitude translation algorithm. Using the spatial compensation parameters, the channel signals corresponding to the channel to be compensated in the spatial audio signal to be rendered are sequentially subjected to gain processing, delay processing, equalization processing, and full-pass filtering processing to generate the audio signal of the headrest speaker corresponding to the seat equipped with the headrest speaker; the seat equipped with the headrest speaker includes the driver's seat and / or the passenger seat.

[0010] Optionally, the step of processing the channel signal corresponding to the channel to be compensated in the audio signal of the rendering space using the spatial compensation parameters according to the processing method corresponding to the current rendering mode to generate the audio signal of the headrest speaker includes: If the current rendering mode is headrest mode, then the audio signal of the space to be rendered is distinguished by signal type to obtain the sound bed signal and the object signal; The acoustic bed signal corresponding to the channel to be compensated in the acoustic bed signal is processed by head-related transfer function, and the acoustic bed signal after head-related transfer function processing is processed by the spatial compensation parameter to obtain the target acoustic bed signal, and the target acoustic bed signal is output to the two independent channels of the headrest speaker; The headrest speaker is used to replace the surround sound channel speaker, the rear surround sound channel speaker, and the rear sky sound channel speaker to form a seat-specific speaker group corresponding to the seat where the headrest speaker is located; Based on the seat-specific speaker group, the object signal is rendered using a speaker rendering algorithm to obtain the object rendering signal of the headrest speaker; the audio signal of the headrest speaker includes the target sound bed signal and the object rendering signal.

[0011] Optionally, the seat-specific speaker group consists of two independent channels of the headrest speaker and one or more of the front channel speaker, the center channel speaker, and the front sky channel speaker that are not obstructed by the seat back, so that the occupant of the seat where the headrest speaker is located can obtain complete multi-channel spatial audio coverage.

[0012] Optionally, rendering the object signal using a speaker rendering algorithm to obtain the object rendering signal of the headrest speaker includes: Obtain the three-dimensional spatial position information of the object signal; Based on the three-dimensional spatial location information and the layout of the seat-specific speaker group, the object signal is rendered to the two independent channels of the headrest speaker using a vector basis amplitude translation algorithm or a head-related transfer function binaural rendering algorithm to obtain the object rendering signal of the headrest speaker.

[0013] Secondly, this application provides an in-vehicle spatial audio output device based on a headrest speaker, comprising: The layout information acquisition module is used to acquire in-vehicle speaker layout information; the in-vehicle speaker layout information includes the position information of each channel speaker in the in-vehicle multi-channel speaker system and the position information of the headrest speakers; the in-vehicle multi-channel speaker system includes multiple front channel speakers, center channel speakers, front overhead channel speakers, surround channel speakers, rear surround channel speakers and rear overhead channel speakers respectively set in different positions in the vehicle; the headrest speakers are speaker groups integrated into the seat headrests and containing two independent channels distributed on both sides of the occupant's head; The compensation parameter calculation module is used to determine the relative spatial position relationship between the seat where the headrest speaker is located and the surround channel speaker, the rear surround channel speaker, and the rear sky channel speaker based on the in-vehicle speaker layout information, and to calculate the spatial compensation parameters from the channel to be compensated to the seat where the headrest speaker is located based on the relative spatial position relationship; the channel to be compensated includes the surround channel, the rear surround channel, and the rear sky channel; the spatial compensation parameters include gain parameters, delay parameters, equalization parameters, and all-pass filter parameters; The rendering mode determination module is used to obtain occupant information and determine the current rendering mode in the full vehicle mode and headrest mode based on the occupant information. The signal rendering module is used to process the channel signal corresponding to the channel to be compensated in the spatial audio signal to be rendered according to the processing method corresponding to the current rendering mode, using the spatial compensation parameters, to generate the audio signal of the headrest speaker, and to perform spatial audio rendering on the spatial audio signal to be rendered, so as to obtain the multi-channel speaker rendering signal corresponding to the in-vehicle multi-channel speaker system. An audio output module is used to synchronously output the audio signal of the headrest speaker and the rendering signal of the multi-channel speaker to compensate for the sound attenuation of the channel to be compensated caused by the obstruction of the seat back.

[0014] Thirdly, this application provides an electronic device, comprising: Memory, used to store computer programs; A processor is used to execute the computer program to implement the aforementioned in-vehicle spatial audio output method based on headrest speakers.

[0015] Fourthly, this application provides a computer-readable storage medium for storing a computer program, wherein the computer program, when executed by a processor, implements the aforementioned in-vehicle spatial audio output method based on headrest speakers.

[0016] This application provides a method for in-vehicle spatial audio output based on headrest speakers. First, it acquires in-vehicle speaker layout information, including the position information of each channel speaker in the in-vehicle multi-channel speaker system and the position information of the headrest speakers. The in-vehicle multi-channel speaker system includes multiple front channel speakers, center channel speakers, front overhead channel speakers, surround channel speakers, rear surround channel speakers, and rear overhead channel speakers, each located at a different position in the vehicle. The headrest speakers are speaker groups integrated into the seat headrest and containing two independent channels distributed on both sides of the occupant's head. Then, based on the in-vehicle speaker layout information, it determines the relative spatial positional relationship between the seat where the headrest speakers are located and the surround channel speakers, rear surround channel speakers, and rear overhead channel speakers, and calculates the distance from the headrest speaker to the channel to be compensated based on the relative spatial positional relationship. The spatial compensation parameters for the seat where the headrest speaker is located are as follows: the channels to be compensated include surround channels, rear surround channels, and rear sky channels; the spatial compensation parameters include gain parameters, delay parameters, equalization parameters, and full-pass filter parameters; then, occupant information is acquired, and the current rendering mode is determined in both full vehicle mode and headrest mode based on the occupant information; next, according to the processing method corresponding to the current rendering mode, the channel signals corresponding to the channels to be compensated in the spatial audio signal to be rendered are processed using the spatial compensation parameters to generate the audio signal of the headrest speaker, and spatial audio rendering is performed on the spatial audio signal to be rendered to obtain the multi-channel speaker rendering signal corresponding to the in-vehicle multi-channel speaker system; finally, the audio signal of the headrest speaker and the multi-channel speaker rendering signal are output synchronously to compensate for the sound attenuation of the channels to be compensated caused by the obstruction of the seat back.

[0017] As can be seen from the above, this application obtains the in-vehicle speaker layout information and determines the relative spatial position relationship between the headrest speaker's seat and the surround, rear surround, and rear sky speakers. It then calculates spatial compensation parameters, including four types of parameters: gain, delay, equalization, and full-pass filtering. Simultaneously, based on in-vehicle occupant information, it determines the current rendering mode in both full-vehicle mode and headrest mode. Following the corresponding mode, it uses the spatial compensation parameters to process the channel signals corresponding to the channels to be compensated in the spatial audio signal to be rendered, generating the headrest speaker audio signal. Simultaneously, it performs conventional spatial audio rendering on the spatial audio signal to be rendered to obtain the multi-channel speaker rendering signal. Ultimately, the audio signals from the headrest speakers and the rendering signals from the multi-channel speakers are output synchronously. This allows for flexible adaptation of rendering strategies to different occupant seating situations. In full-vehicle mode, it considers the listening experience of each seat and effectively compensates for the sound attenuation of surround and rear surround channels caused by seat back obstruction. In headrest mode, the headrest speakers replace the obstructed surround, rear surround, and rear overhead speakers, and combine with the front speakers to form a dedicated rendering speaker group for each seat. This significantly enhances the sense of location and spatial atmosphere of rear sound sources, fully leveraging the synergistic effect of the headrest speakers and other speakers in the vehicle to comprehensively improve the immersive experience of in-vehicle spatial audio. This overcomes the adverse effects of seat back obstruction on rear channels, restoring the spatial atmosphere and sound source location of in-vehicle audio. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0019] Figure 1 This is a schematic diagram illustrating a typical speaker layout in a car and the problem of seat obstruction. Figure 2 This is a flowchart of an in-vehicle spatial audio output method based on a headrest speaker, as disclosed in this invention. Figure 3 This is a schematic diagram of a headrest speaker signal generation disclosed in this invention; Figure 4 This is a schematic diagram of a driver / passenger dedicated speaker assembly disclosed in this invention; Figure 5 This is a schematic diagram of an in-vehicle audio output device based on a headrest speaker disclosed in this invention; Figure 6 This is a structural diagram of an electronic device disclosed in this invention. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] With the improvement of automotive intelligence and the continuous upgrading of cabin experience, in-car audio systems are evolving from traditional stereo playback to multi-channel spatial audio. Currently, mainstream high-end models are equipped with multi-channel speaker systems such as 5.1, 5.1.4, 7.1, and 7.1.4, while more and more models are beginning to integrate speakers into the seat headrests. However, the speakers in the surround sound, rear surround sound, and rear overhead sound channels are mostly located behind or to the sides of the occupants. Their sound waves are often blocked by the seat back and headrests before reaching the occupants' ears, resulting in significant energy attenuation and mid-to-high frequency loss. This weakens the sense of spatial atmosphere and blurs the location of rear objects. Furthermore, in existing solutions, headrest speakers are typically used only as independent channels for personalized audio content such as navigation prompts and phone calls, and are not integrated into a unified spatial audio rendering system. The differences in gain, delay, frequency response, and phase between the two types of speakers are not uniformly considered, and problems such as sound image splitting, positioning deviation, and timbre coloration easily occur during sound output. In addition, existing rendering strategies are relatively fixed and lack flexible switching mechanisms for scenarios such as multi-person listening throughout the vehicle or single-person listening. Therefore, this application provides an in-vehicle spatial audio output solution based on headrest speakers, which can overcome the adverse effects of seat back obstruction on the rear channels and restore the spatial atmosphere and location of sound sources in the in-vehicle audio.

[0022] See Figure 2 As shown in the figure, this application discloses a method for in-vehicle spatial audio output based on headrest speakers, including: Step S11: Obtain the speaker layout information inside the vehicle.

[0023] In this embodiment, the in-vehicle speaker layout information includes the position information of each channel speaker in the in-vehicle multi-channel speaker system and the position information of the headrest speaker; the in-vehicle multi-channel speaker system includes multiple front channel speakers, center channel speakers, front sky channel speakers, surround channel speakers, rear surround channel speakers and rear sky channel speakers respectively disposed in different positions in the vehicle; the headrest speaker is a speaker group integrated in the seat headrest and containing two independent channels distributed on both sides of the occupant's head.

[0024] In this embodiment, the in-vehicle multi-channel speaker system refers to a multi-channel system traditionally composed of speakers distributed throughout the vehicle, used to achieve basic rendering of multi-channel spatial audio. This system supports various channel layouts, including but not limited to: 5.1 layout (left front FL, right front FR, center C, left surround SL, right surround SR, and low-frequency effect LFE); 5.1.4 layout (adding left front sky TFL, right front sky TFR, left rear sky TRL, and right rear sky TRR to the 5.1 layout); 7.1 layout (adding left rear surround RL and right rear surround RR to the 5.1 layout); and 7.1.4 layout (adding the above four sky channels to the 7.1 layout). Each speaker is arranged according to the in-vehicle acoustic design in locations such as the dashboard, doors, rear window sill, and roof, collectively forming the basic playback environment for in-vehicle spatial audio. It should be noted that in full vehicle mode, the system undertakes the main spatial audio rendering task; while in headrest mode, the front channel speakers FL, FR, center channel speaker C, and front sky channel speakers TFL, TFR in the system still participate in signal rendering as components of the rendering speakers.

[0025] The headrest speaker system refers to a near-field speaker assembly integrated into the headrest of the seat. It can be distributed in the headrests of the driver, front passenger, and even other seats, with each seat equipped with one headrest speaker set containing two independent channel speaker units, located on the left and right sides of the occupant's head, forming a near-field dual-channel playback capability. Compared to traditional in-vehicle speakers, headrest speakers have the following characteristics: First, near-field playback, being extremely close to the occupant's ears, with minimal impact from seat back obstruction; second, independent dual channels, enabling differentiated signal output to the left and right ears, providing a foundation for spatial audio rendering algorithms such as Head-Related Transfer Function (HRTF) binaural rendering and Vector Base Amplitude Panning (VBAP); third, acoustic isolation, the near-field characteristics of the headrest speakers minimize interference with other seats, facilitating independent rendering at the seat level.

[0026] In some specific implementations, the in-vehicle speaker layout information can be pre-calibrated in three-dimensional coordinates and stored in the non-volatile memory of the in-vehicle audio host at the factory, and directly read and retrieved after the audio host is powered on; alternatively, it can be dynamically obtained from the vehicle configuration management module via in-vehicle Ethernet or CAN communication to adapt to the differences in the number and layout of speakers in different configuration models under the same platform. It should be noted that since the headrest speakers move with the fore-and-aft adjustment of the seat and the backrest angle adjustment, their position information can also be dynamically corrected in conjunction with the real-time output of the seat position sensor to ensure the accuracy of subsequent spatial compensation parameter calculations.

[0027] Step S12: Determine the relative spatial position relationship between the seat where the headrest speaker is located and the surround sound speaker, the rear surround sound speaker and the rear sky sound speaker based on the in-vehicle speaker layout information, and calculate the spatial compensation parameters from the channel to be compensated to the seat where the headrest speaker is located based on the relative spatial position relationship.

[0028] In this embodiment, the channels to be compensated include surround channels, rear surround channels, and rear sky channels; the spatial compensation parameters include gain parameters, delay parameters, equalization parameters, and all-pass filter parameters. In this embodiment, surround channels, rear surround channels, and rear sky channels are identified as the channels to be compensated because the speakers of these three types of channels are located behind or to the side of the occupant, and their direct sound path is blocked by the seat back and headrest; while the front channel speakers, center channel speakers, and front sky channel speakers are located in front of or above the occupant, and their sound wave propagation path is not blocked by the seat back, thus requiring no compensation. The relative spatial position relationship includes the distance, azimuth angle, and pitch angle from the headrest speaker's seat to each of the left surround (SL), right surround (SR), left rear surround (RL), right rear surround (RR), left rear sky (TRL), and right rear sky (TRR) speakers, which can be calculated from the speaker position information obtained in step S11 and the listening point position of the seat. The input to the spatial compensation parameter calculation module is the aforementioned in-vehicle speaker layout information, and the output is a set of spatial compensation parameters from each channel to be compensated to each seat. Specifically, the calculation of the spatial compensation parameters from the channel to be compensated to the seat where the headrest speaker is located based on the relative spatial position relationship may include: calculating the gain parameter based on the distance from the seat where the headrest speaker is located to the surround channel speaker, the rear surround channel speaker, and the rear sky channel speaker, as well as the degree of obstruction of the channel to be compensated by the seat back.

[0029] In this embodiment, the gain parameter is used to compensate for the sound pressure level loss caused by both distance attenuation and seat back obstruction. The degree of obstruction can be calibrated by measuring the sound pressure level of each speaker in the channel to be compensated at the listening point under two conditions: with and without seat obstruction, during a whole-vehicle acoustic test. The difference between these measurements is taken as the obstruction attenuation of that channel. The greater the distance and the greater the obstruction attenuation of a channel, the larger the corresponding gain parameter value should be. It should be noted that an upper limit should be set for the gain parameter value to avoid the headrest speakers from exceeding their linear operating range and causing distortion, while also preventing the headrest speakers from having excessively strong sound pressure that overwhelms the sound image, causing the overall sound image to shift forward or collapse towards the sides of the head.

[0030] Furthermore, the delay parameter is calculated based on the difference in sound wave propagation paths from the channel to be compensated to the seat where the headrest speaker is located, in order to align the time difference between the headrest speaker and the surround channel speaker, the rear surround channel speaker, and the rear sky channel speaker reaching the occupant's ears. In this embodiment, since the headrest speaker is very close to the occupant's ears, while the surround, rear surround, and rear sky channel speakers are relatively far from the occupant, there is a significant difference in the arrival time of their sound waves. If not aligned, the sound waves from the headrest speaker that arrive first will form a Haas effect, causing the sound image to be pulled to one side of the headrest speaker, thus disrupting the original sense of sound source location. Specifically, the required compensation time can be determined based on the path difference and sound velocity between the channel to be compensated and the headrest speaker to the listening point, and a corresponding delay is applied to the signal played by the headrest speaker, so that it arrives at the occupant's ears synchronously with the corresponding far-field speaker sound waves, thereby merging into a single, stable sound image in the auditory perception.

[0031] Furthermore, the equalization parameters are calculated based on the absorption and reflection characteristics of the seat back at different frequency bands to compensate for the frequency response distortion caused by the seat back obstruction. In this embodiment, the seat back and headrest are mostly made of foam material, leather, and fabric. Their absorption of sound waves increases with frequency, so the attenuation caused by obstruction is not flat in the frequency domain, usually showing significant loss in the mid-high frequencies and relatively small loss in the low frequencies. If only broadband gain compensation is applied, the timbre after compensation will deviate from the original channel. Specifically, the frequency response of each speaker in the channel to be compensated can be collected at the listening point under conditions of seat obstruction and no seat obstruction. The differences between the two in each frequency band can be compared to obtain the frequency response distortion of the channel caused by obstruction. The equalization parameters are set according to the opposite trend of this distortion, boosting the frequency band with greater loss. This can be achieved through a multi-band parametric equalizer or FIR filter, thereby restoring the timbre balance of the original channel.

[0032] Furthermore, the all-pass filter parameters are calculated based on the phase distortion caused by multipath reflections and seat back obstruction, in order to adjust the phase response of the channel to be compensated without changing the amplitude response. In this embodiment, the vehicle interior is small and has many interfaces. Sound waves are reflected multiple times by surfaces such as windows, ceiling, and seats, and then superimposed with the direct sound. In addition, the diffraction effect of the seat back introduces nonlinear phase shifts in various frequency bands. This type of phase distortion cannot be eliminated by gain and equalization processing. If the signals from the headrest speakers and far-field speakers are not in phase, their superposition will produce a comb filtering effect in some frequency bands, resulting in a hollow tone and diffuse sound image. The all-pass filter parameters are used to correct the phase while keeping the amplitude response of each frequency band unchanged. They can be determined by fitting the deviation between the measured phase response at the listening point and the target phase response, and are implemented through an all-pass filter.

[0033] It should be noted that the above-mentioned gain parameters, delay parameters, equalization parameters, and all-pass filter parameters can be uniformly calibrated through whole-vehicle acoustic tests during the vehicle development stage, and stored as parameter tables according to working conditions such as seat position and backrest angle; when the vehicle is running, the table is looked up and interpolated according to the real-time status of the seat, so that the accuracy of compensation can still be maintained after the seat is adjusted.

[0034] Step S13: Obtain occupant information and determine the current rendering mode in the full vehicle mode and headrest mode based on the occupant information.

[0035] In this embodiment, considering that the number of occupants and their seating positions vary significantly in different travel scenarios, using the same rendering strategy throughout would make it difficult to balance the auditory fairness of multiple passengers and the immersive experience required for single passengers. Therefore, the mode switching control module dynamically selects the rendering mode based on real-time occupant information. Specifically, determining the current rendering mode may include: Occupant information is acquired through preset occupant detection sensors, including seat pressure sensors and / or cameras. The seat pressure sensors are located inside the seat cushions and determine whether an occupant is seated by detecting whether the pressure value exceeds a preset pressure threshold. The camera can be a cabin monitoring camera, which identifies the occupancy status of each seat by performing face or body detection on the captured images. In some specific embodiments, the detection results of both sensors can be fused for judgment to avoid misjudgments caused by items placed on the seats.

[0036] If the occupant information indicates that there are occupants in multiple seats inside the vehicle, then the full vehicle mode is determined as the current rendering mode. The full vehicle mode is suitable for scenarios where there are occupants in multiple seats inside the vehicle. Its principle is to ensure the basic spatial audio effect of the entire vehicle, while using headrest speakers to compensate for the surround sound attenuation of the driver / passenger seats, thus taking into account the listening experience of all seats in the vehicle.

[0037] If the occupant information indicates that only the driver's seat or only the front passenger seat has an occupant, then the headrest mode is determined as the current rendering mode, and the driver's seat or front passenger seat with an occupant is determined as the seat where the headrest speaker is located. The driver / front passenger headrest mode is suitable for scenarios where only the driver or front passenger is present. In this mode, the listening effect of the driver / front passenger is prioritized, making full use of the near-field advantage of the headrest speaker to achieve an immersive spatial audio experience at the seat level. Since there are no other listeners in the car at this time, the listening effect of other seats is not guaranteed, so all rendering resources can be concentrated on this seat.

[0038] If a mode selection command is received from the user, the rendering mode corresponding to the command will be determined as the current rendering mode. The mode selection command can be input via the vehicle's central control screen, steering wheel buttons, or voice interaction. It should be noted that mode switching can be automatically triggered by the aforementioned occupant detection sensors or manually selected by the user. Furthermore, the user-input mode selection command has higher priority than the automatic judgment result to respect the user's subjective listening preferences; for example, when multiple passengers are traveling but the remaining passengers are resting, the user can manually switch to headrest mode.

[0039] Step S14: According to the processing method corresponding to the current rendering mode, the channel signal corresponding to the channel to be compensated in the spatial audio signal to be rendered is processed using the spatial compensation parameters to generate the audio signal of the headrest speaker, and the spatial audio signal to be rendered is spatial audio rendered to obtain the multi-channel speaker rendering signal corresponding to the in-vehicle multi-channel speaker system.

[0040] In this embodiment, the above processing is performed by a speaker rendering module, which includes a regular rendering submodule and a headrest rendering submodule. The regular rendering submodule uses a regular speaker rendering algorithm to perform spatial audio rendering on speakers other than the headrests to ensure basic spatial audio effects throughout the vehicle, and is mainly used in the full vehicle mode. The headrest rendering submodule processes the corresponding channel signals according to the current rendering mode and generates audio signals for the headrest speakers. The spatial audio signals to be rendered are object-oriented audio format signals, which include two types: bed signals and object signals. Bed signals are signals corresponding to fixed channels, and object signals are independent audio signals carrying three-dimensional spatial location metadata. Different processing methods are used for the full vehicle mode and the headrest mode. Specifically, if the current rendering mode is the full vehicle mode, a preset speaker rendering algorithm is used to perform spatial audio rendering on the spatial audio signals to be rendered to obtain multi-channel speaker rendering signals corresponding to the in-vehicle multi-channel speaker system. The preset speaker rendering algorithm includes a vector basis amplitude translation algorithm.

[0041] In this embodiment, the vector basis amplitude translation algorithm selects several speakers surrounding the three-dimensional spatial position of the object signal from the in-vehicle multi-channel speaker system to form a speaker group. By allocating gain among the speakers within the group, the synthesized virtual sound source is directed towards the target position. Accordingly, the sound bed signal is directly mapped to the corresponding channel speaker according to its channel definition, and the object signal is rendered by the above algorithm and superimposed on each channel to jointly constitute the multi-channel speaker rendering signal, thereby ensuring the basic spatial audio effect of all seats in the vehicle.

[0042] See Figure 3As shown, in full vehicle mode, using the spatial compensation parameters, the channel signals corresponding to the channel to be compensated in the spatial audio signal to be rendered are sequentially subjected to gain processing, delay processing, equalization processing, and full-pass filtering processing to generate the audio signal of the headrest speaker corresponding to the seat equipped with the headrest speaker; the seat equipped with the headrest speaker includes the driver's seat and / or the passenger seat.

[0043] Specifically, the audio channels are allocated according to their left and right orientation: the signals from the left surround channel (SL), left rear surround channel (RL), and left rear sky channel (TRL) are processed by their respective gain, delay, equalization, and full-pass filtering, and then superimposed to obtain the audio signal for the left headrest channel; the signals from the right surround channel (SR), right rear surround channel (RR), and right rear sky channel (TRR) are processed in the same way and then superimposed to obtain the audio signal for the right headrest channel. These four types of processing are executed sequentially in series, with gain processing recovering lost sound energy, delay processing aligning arrival times, equalization processing correcting timbre deviations, and full-pass filtering eliminating phase distortion. If both the driver's and passenger's seats are equipped with headrest speakers, the above processing is performed separately for the spatial compensation parameters of each seat, generating audio signals for the driver's and passenger's headrest speakers.

[0044] It should be noted that in full vehicle mode, the surround channel speakers, rear surround channel speakers, and rear overhead channel speakers still operate normally. The signals played by the headrest speakers only supplement the aforementioned channels, compensating for the sound energy lost due to obstruction by the seat back. Together, they restore a near-unobstructed listening experience at the listening point. Due to the application of delay alignment and phase correction, the compensated sound from the headrest speakers and the direct sound from the far-field speakers are perceived as a single sound image, without forming additional, separately perceptible near-field sound sources. This enhances the spatial atmosphere of the rear channels without altering the original sound field structure.

[0045] If the current rendering mode is headrest mode, the spatial audio signal to be rendered is distinguished by signal type to obtain a bed signal and an object signal. In this embodiment, the signal type can be distinguished according to the metadata identifier in the objectified audio bitstream. The object signal carries three-dimensional spatial position information, while the others are bound to fixed channels and are bed signals. The reason for using different rendering strategies for the two types of signals in headrest mode is that the bed signal corresponds to a fixed channel orientation, and it is appropriate to use binaural rendering to reconstruct its orientation; while the spatial position of the object signal changes dynamically over time, and it is appropriate to use a translation algorithm based on speaker layout to render it in order to maintain the continuity of its motion trajectory. The bed signal corresponding to the channel to be compensated in the bed signal is processed by a head-related transfer function, and the spatial compensation parameters are used to process the bed signal after the head-related transfer function processing to obtain the target bed signal, and the target bed signal is output to the two independent channels of the headrest speaker.

[0046] In this embodiment, the head-related transfer function describes the filtering effect of sound waves propagating from a certain direction in space to the listener's ears, including localization cues such as binaural time difference, binaural sound level difference, and spectral characteristics introduced by the auricle. Since the headrest speakers are close to the occupant's ears, the signals they play are approximately binaural signals. Therefore, by applying the head-related transfer function corresponding to the original channel orientation to the sound bed signals of the left surround (SL), right surround (SR), left rear surround (RL), right rear surround (RR), left rear sky (TRL), and right rear sky (TRR), the occupant can perceive that the sound comes from the original spatial orientation of that channel, thereby reconstructing the obstructed surround, rear surround, and rear sky sound fields on the headrest speakers. Subsequently, the spatial compensation parameters obtained in step S12 are used to process the above results and output them to the two independent channels of the corresponding seat headrest speakers.

[0047] See Figure 4 As shown, the headrest speaker replaces the surround channel speaker, the rear surround channel speaker, and the rear sky channel speaker to form a seat-specific speaker group corresponding to the seat where the headrest speaker is located. It should be noted that... Figure 4 The speakers marked with solid circles are the speakers that make up the speaker group dedicated to the seat. Specifically, they include the left and right independent channels of the headrest speaker, as well as the left front channel speaker FL, right front channel speaker FR, center channel speaker C, left front sky channel speaker TFL, and right front sky channel speaker TFR, which are not blocked by the seat back. The surround channel speakers, rear surround channel speakers, and rear sky channel speakers that are blocked by the seat back do not participate in the spatial audio rendering of the seat.

[0048] In this embodiment, unlike the full-vehicle mode where the headrest speakers only serve a compensating function, in headrest mode, the headrest speakers directly replace the blocked surround, rear surround, and rear sky speakers to perform the reproduction task of the rear channels. The reason for this is that the sound waves from the aforementioned far-field speakers are inevitably blocked by the seat back, and even with compensation, they are difficult to fully recover; while the headrest speakers are located outside the obstruction and can directly project signals to the occupant's ears, resulting in superior positioning accuracy and timbre fidelity compared to the far-field speakers after attenuation due to obstruction.

[0049] Specifically, the seat-specific speaker group consists of two independent channels from the headrest speaker, and one or more of the front channel speaker, center channel speaker, and front overhead channel speaker that are not obstructed by the seat back, to provide the occupant in the seat where the headrest speaker is located with complete multi-channel spatial audio coverage. That is, the two independent channels of the headrest speaker replace the surround, rear surround, and rear overhead speakers obstructed by the seat back, and together with the unobstructed left front channel (FL), right front channel (FR), center channel (C), left front overhead channel (TFL), and right front overhead channel (TFR) speakers, form the driver's or passenger's dedicated soundstage speaker group. In this way, the front sound field is still handled by the unobstructed far-field speakers to maintain the openness and depth of the front sound image; the rear and overhead sound fields are handled by the headrest channels. Together, they form a complete virtual speaker layout surrounding the occupant, balancing the spatial sense of the far-field speakers with the clarity of the near-field speakers.

[0050] Based on the seat-specific speaker group, the object signal is rendered using a speaker rendering algorithm to obtain the object rendering signal of the headrest speaker; the audio signal of the headrest speaker includes the target sound bed signal and the object rendering signal.

[0051] Specifically, the step of rendering the object signal using a speaker rendering algorithm to obtain the object rendering signal of the headrest speaker includes: acquiring the three-dimensional spatial position information of the object signal; and, based on the three-dimensional spatial position information and the layout of the seat-specific speaker group, rendering the object signal to the two independent channels of the headrest speaker using a vector basis amplitude translation algorithm or a head-related transfer function binaural rendering algorithm to obtain the object rendering signal of the headrest speaker.

[0052] In this embodiment, the three-dimensional spatial location information can be obtained by parsing the metadata of the objectified audio bitstream, typically represented by azimuth, pitch, and distance. When the object sound source is located in front of the occupant, it is mainly rendered by the front far-field speakers; when the object sound source is located to the side or above the rear of the occupant, it is mainly rendered by the headrest channels; when the object sound source moves across the front and rear areas, a smooth transition is achieved by gain translation between the front speakers and the headrest channels to avoid sound image jumps. In some specific implementations, for object signals with high azimuth accuracy requirements, the head-related transfer function binaural rendering algorithm can be preferentially used to obtain more accurate spatial positioning; for object signals with high movement speed or a large number of objects, the vector basis amplitude translation algorithm with lower computational load can be used to reduce the real-time processing load of the system.

[0053] It should be noted that, thanks to the acoustic isolation of the headrest speakers, their output signals have minimal interference with other seats, thus enabling independent rendering at the seat level in headrest mode. If both the driver's and front passenger's seats are equipped with headrest speakers and both have occupants, separate speaker groups can be created for each seat and rendered independently, allowing both occupants to simultaneously enjoy their optimal listening experience.

[0054] Step S15: Synchronously output the audio signal of the headrest speaker and the rendering signal of the multi-channel speaker to compensate for the sound attenuation of the channel to be compensated caused by the obstruction of the seat back.

[0055] In this embodiment, the synchronous output refers to the audio signal from the headrest speaker and the rendering signal from the multi-channel speaker being sent to each speaker unit after digital-to-analog conversion and power amplification under the same clock domain, to ensure strict time alignment between the two, thereby achieving coordinated operation between the headrest speaker and other speakers. In some specific implementations, the digital signal processor in the vehicle audio head unit can uniformly process the above two signals and distribute the channel signals to the corresponding power amplifier modules via A2B (Automotive AudioBus) or vehicle Ethernet. Each power amplifier module outputs based on the bus synchronous clock, thereby eliminating the additional time delay difference between channels. If the two outputs are not synchronized, the delay parameter calculated in step S12 will be meaningless, and the aforementioned sound image fusion effect cannot be achieved.

[0056] It should be noted that, considering that the masking effect of road noise and wind noise will aggravate the hearing loss of the rear channel when the vehicle speed increases, in some specific implementations, the gain parameters can be dynamically corrected according to the vehicle speed signal reported by the vehicle CAN bus. That is, the higher the vehicle speed, the more the compensation gain of the headrest speakers is increased to maintain a stable spatial audio listening experience.

[0057] As can be seen from the above, this embodiment incorporates the headrest speakers into a unified spatial audio rendering system and calculates spatial compensation parameters, including four types of parameters: gain, delay, equalization, and full-pass filtering, based on speaker layout information. This enables the headrest speakers and the in-vehicle multi-channel speaker system to work together in four dimensions: energy, time, frequency, and phase. This effectively compensates for the sound attenuation of the surround and rear surround channels caused by the obstruction of the seat back, significantly enhances the spatial atmosphere of the in-vehicle audio, and restores the sense of location of rear sound sources such as surround, rear surround, and rear sky, thus improving the immersive experience of spatial audio. In full-vehicle mode, the headrest speakers, as a supplement to the rear channels, compensate for sound energy loss without destroying the original sound field structure, taking into account the listening experience of all occupants in the vehicle. In headrest mode, the headrest speakers replace the obstructed rear far-field speakers and, together with the unobstructed front speakers, form a seat-specific speaker group. Through head-related transfer function processing and speaker rendering algorithms, a complete three-dimensional sound field is reconstructed, fully leveraging the spatial audio enhancement potential of the headrest speakers. Meanwhile, the system automatically switches between two modes based on occupant detection results and supports manual selection by the user, enabling the rendering strategy to flexibly adapt to different usage scenarios such as multi-person listening throughout the vehicle and single-person exclusive listening. This overcomes the adverse effects of seat back obstruction on the rear audio channels and restores the spatial atmosphere and sound source location of the in-vehicle audio.

[0058] See Figure 5 As shown in the figure, this application discloses an in-vehicle audio output device based on a headrest speaker, comprising: The layout information acquisition module 11 is used to acquire in-vehicle speaker layout information; the in-vehicle speaker layout information includes the position information of each channel speaker in the in-vehicle multi-channel speaker system and the position information of the headrest speakers; the in-vehicle multi-channel speaker system includes multiple front channel speakers, center channel speakers, front overhead channel speakers, surround channel speakers, rear surround channel speakers and rear overhead channel speakers respectively set in different positions in the vehicle; the headrest speakers are speaker groups integrated into the seat headrests and containing two independent channels distributed on both sides of the occupant's head; The compensation parameter calculation module 12 is used to determine the relative spatial position relationship between the seat where the headrest speaker is located and the surround channel speaker, the rear surround channel speaker, and the rear sky channel speaker based on the in-vehicle speaker layout information, and to calculate the spatial compensation parameters from the channel to be compensated to the seat where the headrest speaker is located based on the relative spatial position relationship; the channel to be compensated includes the surround channel, the rear surround channel, and the rear sky channel; the spatial compensation parameters include gain parameters, delay parameters, equalization parameters, and all-pass filter parameters; The rendering mode determination module 13 is used to obtain occupant information and determine the current rendering mode in the full vehicle mode and headrest mode based on the occupant information. The signal rendering module 14 is used to process the channel signal corresponding to the channel to be compensated in the spatial audio signal to be rendered according to the processing method corresponding to the current rendering mode, using the spatial compensation parameters, to generate the audio signal of the headrest speaker, and to perform spatial audio rendering on the spatial audio signal to be rendered, so as to obtain the multi-channel speaker rendering signal corresponding to the in-vehicle multi-channel speaker system. The audio output module 15 is used to synchronously output the audio signal of the headrest speaker and the rendering signal of the multi-channel speaker to compensate for the sound attenuation of the channel to be compensated caused by the obstruction of the seat back.

[0059] In some specific embodiments, the compensation parameter calculation module 12 may specifically include: The gain parameter determination unit is used to calculate the gain parameter based on the distance from the seat where the headrest speaker is located to the surround channel speaker, the rear surround channel speaker and the rear sky channel speaker, as well as the degree of obstruction of the seat back to the channel to be compensated. The delay parameter determination unit is used to calculate the delay parameter based on the sound wave propagation path difference from the channel to be compensated to the seat where the headrest speaker is located, so as to align the time difference between the headrest speaker and the surround channel speaker, the rear surround channel speaker and the rear sky channel speaker reaching the occupant's ear. The equalization parameter determination unit is used to calculate the equalization parameters based on the absorption and reflection characteristics of the seat back for different frequency bands, so as to compensate for the frequency response distortion caused by the obstruction of the seat back. The all-pass filter parameter determination unit is used to calculate the all-pass filter parameters based on the phase distortion caused by multipath reflection and seat back obstruction, so as to adjust the phase response of the channel to be compensated without changing the amplitude response.

[0060] In some specific embodiments, the rendering mode determination module 13 may specifically include: The occupant information acquisition unit is used to acquire occupant information inside the vehicle through preset occupant detection sensors; the preset occupant detection sensors include a seat pressure sensor and / or a camera. The first mode determination unit is used to determine the full vehicle mode as the current rendering mode if the occupant information indicates that there are occupants in multiple seats in the vehicle. The second mode determination unit is used to determine the headrest mode as the current rendering mode if the occupant information indicates that there is only an occupant in the driver's seat or only an occupant in the front passenger seat, and to determine the driver's seat or front passenger seat with an occupant as the seat where the headrest speaker is located. The third mode determination unit is used to determine the rendering mode corresponding to the mode selection instruction as the current rendering mode if it receives a mode selection instruction input by the user.

[0061] In some specific embodiments, the signal rendering module 14 may specifically include: The full-vehicle rendering signal generation unit is used to perform spatial audio rendering on the spatial audio signal to be rendered using a preset speaker rendering algorithm if the current rendering mode is full-vehicle mode, so as to obtain a multi-channel speaker rendering signal corresponding to the in-vehicle multi-channel speaker system; the preset speaker rendering algorithm includes a vector basis amplitude translation algorithm. The full-vehicle rendering audio generation unit is used to perform gain processing, delay processing, equalization processing, and full-pass filtering processing on the channel signals corresponding to the channel to be compensated in the spatial audio signal to be rendered in sequence using the spatial compensation parameters, so as to generate the audio signal of the headrest speaker corresponding to the seat equipped with the headrest speaker; the seat equipped with the headrest speaker includes the driver's seat and / or the passenger seat.

[0062] The signal differentiation unit is used to differentiate the signal type of the spatial audio signal to be rendered if the current rendering mode is the headrest mode, so as to obtain the sound bed signal and the object signal. The acoustic bed signal generation unit is used to perform head-related transfer function processing on the acoustic bed signal corresponding to the acoustic channel to be compensated in the acoustic bed signal, and to process the acoustic bed signal after head-related transfer function processing using the spatial compensation parameters to obtain the target acoustic bed signal, and to output the target acoustic bed signal to the two independent channels of the headrest speaker; A dedicated speaker group determining unit is used to replace the surround channel speaker, the rear surround channel speaker, and the rear sky channel speaker with the headrest speaker to form a seat-specific speaker group corresponding to the seat where the headrest speaker is located; the seat-specific speaker group is composed of the two independent channels of the headrest speaker and one or more of the front channel speaker, the center channel speaker, and the front sky channel speaker that are not blocked by the seat back, so that the occupant of the seat where the headrest speaker is located can obtain complete multi-channel spatial audio coverage. The object rendering signal generation submodule is used to render the object signal based on the seat-specific speaker group using a speaker rendering algorithm to obtain the object rendering signal of the headrest speaker; the audio signal of the headrest speaker includes the target sound bed signal and the object rendering signal; Accordingly, the object rendering signal generation submodule may specifically include: A three-dimensional spatial position information acquisition unit is used to acquire the three-dimensional spatial position information of the object signal; The object rendering signal generation unit is used to render the object signal to the two independent channels of the headrest speaker based on the three-dimensional spatial position information and the layout of the seat-specific speaker group, using a vector basis amplitude translation algorithm or a head-related transfer function binaural rendering algorithm, so as to obtain the object rendering signal of the headrest speaker.

[0063] Furthermore, embodiments of this application also disclose an electronic device, Figure 6 This is a structural diagram of an electronic device 20 according to an exemplary embodiment. The content of the diagram should not be construed as limiting the scope of this application. The electronic device 20 may specifically include: at least one processor 21, at least one memory 22, a power supply 23, a communication interface 24, an input / output interface 25, and a communication bus 26. The memory 22 stores a computer program, which is loaded and executed by the processor 21 to implement the relevant steps in the in-vehicle audio output method based on headrest speakers disclosed in any of the foregoing embodiments. Furthermore, the electronic device 20 in this embodiment may specifically be a computer.

[0064] In this embodiment, the power supply 23 is used to provide operating voltage for each hardware device on the electronic device 20; the communication interface 24 can create a data transmission channel between the electronic device 20 and external devices, and the communication protocol it follows can be any communication protocol applicable to the technical solution of this application, and is not specifically limited here; the input / output interface 25 is used to acquire external input data or output data to the outside world, and its specific interface type can be selected according to specific application needs, and is not specifically limited here.

[0065] In addition, the memory 22, as a carrier for resource storage, can be a read-only memory, random access memory, disk or optical disk, etc. The resources stored thereon can include operating system 221, computer program 222, etc., and the storage method can be temporary storage or permanent storage.

[0066] The operating system 221 is used to manage and control the various hardware devices on the electronic device 20 and the computer program 222, which may be Windows Server, Netware, Unix, Linux, etc. In addition to including a computer program capable of performing the in-vehicle spatial audio output method based on a headrest speaker as disclosed in any of the foregoing embodiments, the computer program 222 may further include computer programs capable of performing other specific tasks.

[0067] Furthermore, this application also discloses a computer-readable storage medium for storing a computer program; wherein, when the computer program is executed by a processor, it implements the aforementioned disclosed method for in-vehicle spatial audio output based on headrest speakers. Specific steps of this method can be found in the corresponding content disclosed in the foregoing embodiments, and will not be repeated here.

[0068] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to in the method section.

[0069] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0070] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0071] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0072] The technical solutions provided in this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for in-vehicle spatial audio output based on headrest speakers, characterized in that, include: Obtain information on the layout of the vehicle's speakers; The in-vehicle speaker layout information includes the position information of each channel speaker in the in-vehicle multi-channel speaker system and the position information of the headrest speakers. The in-vehicle multi-channel speaker system includes multiple front channel speakers, center channel speakers, front overhead channel speakers, surround channel speakers, rear surround channel speakers, and rear overhead channel speakers, which are respectively installed in different positions in the vehicle; the headrest speakers are speaker groups integrated into the seat headrests and containing two independent channels distributed on both sides of the occupant's head. The relative spatial relationship between the headrest speaker's location and the surround sound speakers, the rear surround sound speakers, and the rear sky sound speakers is determined based on the in-vehicle speaker layout information. Spatial compensation parameters from the channel to be compensated to the headrest speaker's location are then calculated based on this relative spatial relationship. The channel to be compensated includes the surround sound channel, the rear surround sound channel, and the rear sky sound channel. The spatial compensation parameters include gain parameters, delay parameters, equalization parameters, and all-pass filter parameters. Obtain information about the occupants inside the vehicle, and determine the current rendering mode in both the full vehicle mode and the headrest mode based on the occupant information. According to the processing method corresponding to the current rendering mode, the channel signal corresponding to the channel to be compensated in the spatial audio signal to be rendered is processed using the spatial compensation parameters to generate the audio signal of the headrest speaker, and spatial audio rendering is performed on the spatial audio signal to be rendered to obtain the multi-channel speaker rendering signal corresponding to the in-vehicle multi-channel speaker system. The audio signal from the headrest speaker is output synchronously with the rendering signal from the multi-channel speaker to compensate for the sound attenuation of the channel to be compensated caused by the obstruction of the seat back.

2. The in-vehicle spatial audio output method based on headrest speakers according to claim 1, characterized in that, The calculation of spatial compensation parameters from the channel to be compensated to the seat where the headrest speaker is located, based on the relative spatial position relationship, includes: The gain parameter is calculated based on the distance from the seat where the headrest speaker is located to the surround channel speaker, the rear surround channel speaker, and the rear sky channel speaker, as well as the degree of obstruction of the channel to be compensated by the seat back. The delay parameter is calculated based on the difference in sound wave propagation path from the channel to be compensated to the seat where the headrest speaker is located, so as to align the time difference between the headrest speaker and the surround channel speaker, the rear surround channel speaker and the rear sky channel speaker reaching the occupant's ears. The equalization parameters are calculated based on the absorption and reflection characteristics of the seat back at different frequency bands to compensate for the frequency response distortion caused by the obstruction of the seat back. The all-pass filter parameters are calculated based on the phase distortion caused by multipath reflections and seat back obstruction, so as to adjust the phase response of the channel to be compensated without changing the amplitude response.

3. The in-vehicle spatial audio output method based on headrest speakers according to claim 1, characterized in that, Determining the current rendering mode includes: Occupant information is acquired through preset occupant detection sensors; the preset occupant detection sensors include seat pressure sensors and / or cameras. If the occupant information indicates that there are occupants in multiple seats inside the vehicle, then the full vehicle mode is determined as the current rendering mode. If the occupant information indicates that there is only an occupant in the driver's seat or only an occupant in the front passenger seat, then the headrest mode is determined as the current rendering mode, and the driver's seat or front passenger seat with an occupant is determined as the seat where the headrest speaker is located. If a mode selection instruction is received from the user, the rendering mode corresponding to the mode selection instruction will be determined as the current rendering mode.

4. The in-vehicle spatial audio output method based on headrest speakers according to claim 1, characterized in that, The step of processing the channel signal corresponding to the channel to be compensated in the spatial audio signal to be rendered using the spatial compensation parameters according to the processing method corresponding to the current rendering mode, to generate the audio signal of the headrest speaker, and performing spatial audio rendering on the spatial audio signal to be rendered to obtain the multi-channel speaker rendering signal corresponding to the in-vehicle multi-channel speaker system, includes: If the current rendering mode is full vehicle mode, then a preset speaker rendering algorithm is used to perform spatial audio rendering on the spatial audio signal to be rendered, so as to obtain a multi-channel speaker rendering signal corresponding to the in-vehicle multi-channel speaker system; the preset speaker rendering algorithm includes a vector basis amplitude translation algorithm. Using the spatial compensation parameters, the channel signals corresponding to the channel to be compensated in the spatial audio signal to be rendered are sequentially subjected to gain processing, delay processing, equalization processing, and full-pass filtering processing to generate the audio signal of the headrest speaker corresponding to the seat equipped with the headrest speaker; the seat equipped with the headrest speaker includes the driver's seat and / or the passenger seat.

5. The in-vehicle spatial audio output method based on headrest speakers according to claim 1, characterized in that, The step of processing the channel signal corresponding to the channel to be compensated in the audio signal of the rendering space using the spatial compensation parameters according to the processing method corresponding to the current rendering mode, in order to generate the audio signal of the headrest speaker, includes: If the current rendering mode is headrest mode, then the audio signal of the space to be rendered is distinguished by signal type to obtain the sound bed signal and the object signal; The acoustic bed signal corresponding to the channel to be compensated in the acoustic bed signal is processed by head-related transfer function, and the acoustic bed signal after head-related transfer function processing is processed by the spatial compensation parameter to obtain the target acoustic bed signal, and the target acoustic bed signal is output to the two independent channels of the headrest speaker; The headrest speaker is used to replace the surround sound channel speaker, the rear surround sound channel speaker, and the rear sky sound channel speaker to form a seat-specific speaker group corresponding to the seat where the headrest speaker is located; Based on the seat-specific speaker group, the object signal is rendered using a speaker rendering algorithm to obtain the object rendering signal of the headrest speaker; the audio signal of the headrest speaker includes the target sound bed signal and the object rendering signal.

6. The in-vehicle spatial audio output method based on headrest speakers according to claim 5, characterized in that, The seat-specific speaker group consists of two independent channels of the headrest speaker, as well as one or more of the front channel speaker, the center channel speaker, and the front sky channel speaker that are not obstructed by the seat back, so that the occupant of the seat where the headrest speaker is located can obtain complete multi-channel spatial audio coverage.

7. The in-vehicle spatial audio output method based on headrest speakers according to claim 5, characterized in that, The step of rendering the object signal using a speaker rendering algorithm to obtain the object rendering signal of the headrest speaker includes: Obtain the three-dimensional spatial position information of the object signal; Based on the three-dimensional spatial location information and the layout of the seat-specific speaker group, the object signal is rendered to the two independent channels of the headrest speaker using a vector basis amplitude translation algorithm or a head-related transfer function binaural rendering algorithm to obtain the object rendering signal of the headrest speaker.

8. An in-vehicle audio output device based on a headrest speaker, characterized in that, include: The layout information acquisition module is used to acquire the layout information of the in-vehicle speakers; The in-vehicle speaker layout information includes the position information of each channel speaker in the in-vehicle multi-channel speaker system and the position information of the headrest speakers; the in-vehicle multi-channel speaker system includes multiple front channel speakers, center channel speakers, front overhead channel speakers, surround channel speakers, rear surround channel speakers and rear overhead channel speakers respectively set in different positions in the vehicle; the headrest speakers are speaker groups integrated into the seat headrests and containing two independent channels distributed on both sides of the occupant's head; The compensation parameter calculation module is used to determine the relative spatial position relationship between the seat where the headrest speaker is located and the surround channel speaker, the rear surround channel speaker, and the rear sky channel speaker based on the in-vehicle speaker layout information, and to calculate the spatial compensation parameters from the channel to be compensated to the seat where the headrest speaker is located based on the relative spatial position relationship; the channel to be compensated includes the surround channel, the rear surround channel, and the rear sky channel; the spatial compensation parameters include gain parameters, delay parameters, equalization parameters, and all-pass filter parameters; The rendering mode determination module is used to obtain occupant information and determine the current rendering mode in the full vehicle mode and headrest mode based on the occupant information. The signal rendering module is used to process the channel signal corresponding to the channel to be compensated in the spatial audio signal to be rendered according to the processing method corresponding to the current rendering mode, using the spatial compensation parameters, to generate the audio signal of the headrest speaker, and to perform spatial audio rendering on the spatial audio signal to be rendered, so as to obtain the multi-channel speaker rendering signal corresponding to the in-vehicle multi-channel speaker system. An audio output module is used to synchronously output the audio signal of the headrest speaker and the rendering signal of the multi-channel speaker to compensate for the sound attenuation of the channel to be compensated caused by the obstruction of the seat back.

9. An electronic device, characterized in that, include: Memory, used to store computer programs; A processor for executing the computer program to implement the in-vehicle spatial audio output method based on headrest speakers as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, Used to store a computer program, wherein the computer program, when executed by a processor, implements the in-vehicle spatial audio output method based on a headrest speaker as described in any one of claims 1 to 7.

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