Noise reduction method, system and device for vehicle-mounted audio compensation and storage medium

Abstract

The invention relates to the technical field of noise reduction, in particular to a noise reduction method, system and device for vehicle-mounted audio compensation and a storage medium. The noise reduction method for vehicle-mounted audio compensation comprises the following steps: acquiring an audio file needing to be played, and identifying frequency characteristics of the audio file; engine speed characteristics are obtained; and acquiring a frequency range in which the frequency characteristic is matched with the frequency corresponding to the engine rotating speed characteristic, and performing order energy compensation on the audio file in the frequency range. The controller obtains frequency characteristics of the audio files and engine rotating speed characteristics, identifies similar components of frequencies corresponding to the frequency characteristics of the audio files and the engine rotating speed characteristics, calculates and controls compensation moments and compensation signals to perform energy compensation on the audio files with the similar components, eliminates components of music during noise reduction, and reduces noise. The noise reduction only aims at the target sound source and does not aim at the music components, so that the situation that the components in the music are mistakenly eliminated during noise reduction, and the listening feeling of the music is reduced is avoided.

Description

Technical Field

[0001] The present application relates to the technical field of noise reduction, and in particular to a noise reduction method, system, device and storage medium for vehicle audio compensation. Background Art

[0002] Active Noise Cancellation (ANC) systems are often used in vehicles to solve engine noise problems. Active noise cancellation is an adaptive system that can emit a sound with the same amplitude and opposite phase as the target noise in real time, and superimpose it at the desired noise reduction position to achieve sound cancellation.

[0003] Usually, we actively reduce noise to solve the order peak noise in the engine noise component. Its characteristics are: ①: it is a single frequency in the frequency domain, showing a narrow band prominent peak; ②: multiple peaks are in multiple relationship. As shown in the figure. Its formation frequency is determined by the number of ignitions per revolution of the engine crankshaft, that is, the frequency can be calculated based on the engine speed. For example, when the 4-cylinder engine has a revolution per minute of 2100 (rpm), the order noise frequency is 2100*2 / 60=70Hz, 4th order: 2100*4 / 60=140Hz, and 6th order: 2100*6 / 60=210Hz.

[0004] The commonly used notch active noise reduction is to eliminate these single-frequency prominent peaks. The implementation method is to obtain the engine speed signal, calculate the noise frequency that needs to be eliminated (when the engine speed is 2100rpm, 70, 140 and 210Hz are eliminated, and the engine speed will also be tracked and calculated in real time when the engine speed changes), use the frequency signal as a reference signal, input it into the adaptive filter for iteration, and control the adaptive filter to emit reverse sound waves to cancel the noise.

[0005] The characteristic of this method is that the target noise signal to be eliminated is identified only by frequency. That is to say, not only the engine order noise, but also any sound with matching or similar frequency transmitted to the error microphone inside the car may be mistaken for the target noise and eliminated.

[0006] The biggest actual impact is that when playing music through the car audio media, some of the same frequency components in the music will be mistakenly eliminated. The common operating speed of a 4-cylinder engine is 1200-5000rpm, and the order frequency can cover the range of 40Hz-500Hz. In this range of music components, single-frequency drum beats, string instruments, and certain frequency harmonics of human voices will be affected. Mistaken elimination will weaken their energy, causing changes in subjective listening experience and affecting the sound quality effect. Summary of the invention

[0007] The main purpose of the present application is to provide a noise reduction method, system, device and storage medium for vehicle audio compensation, aiming to solve the technical problem that components in audio media music are mistakenly eliminated and the listening experience of music is deteriorated.

[0008] To achieve the above-mentioned purpose, the present application provides a noise reduction method for vehicle audio compensation, the noise reduction method for vehicle audio compensation comprising:

[0009] Obtain an audio file to be played, and identify the frequency characteristics of the audio file;

[0010] Obtain engine speed characteristics;

[0011] A frequency range in which the frequency characteristic matches the frequency corresponding to the engine speed characteristic is obtained, and order energy compensation is performed on the audio file within the frequency range.

[0012] In one embodiment, the step of obtaining an audio file to be played and identifying a frequency feature of the audio file includes:

[0013] Acquire an audio file to be played, and acquire music feature data of the audio file;

[0014] Performing Fourier transform on the music feature data to obtain the frequency feature of the audio file.

[0015] In one embodiment, the acquiring a frequency range in which the frequency characteristic matches the frequency corresponding to the engine speed characteristic, and performing order energy compensation on the audio file within the frequency range, comprises:

[0016] Obtaining a noise reduction order frequency corresponding to the engine speed;

[0017] Determining a frequency range that needs to be compensated in the frequency characteristic according to the noise reduction order frequency;

[0018] Perform order energy compensation on the audio file within the frequency range.

[0019] In one embodiment, performing order energy compensation on the audio file within the frequency range includes:

[0020] Measure the transfer function from the corresponding audio frequency emitted by each speaker to the human ear;

[0021] Calculating a compensation signal of the frequency range that needs to be compensated by using the transfer function;

[0022] The order energy compensation is performed on the frequency range by using the compensation signal.

[0023] In one embodiment, performing order energy compensation on the frequency range by using the compensation signal includes:

[0024] Inputting the compensation signal to an adaptive filter, and outputting a first sound wave at an output end of the adaptive filter by iteratively controlling the weight coefficients of the adaptive filter;

[0025] The order energy compensation is performed on the frequency range by using the first sound wave.

[0026] In one embodiment, after the step of performing order energy compensation on the frequency range by using the first sound wave, the method further includes:

[0027] Convert the current speed of the engine into frequency data and input it into the adaptive filter, and output a second reverse sound wave at the output end of the adaptive filter by controlling the weight coefficient iteration of the adaptive filter;

[0028] The sound transmitted to the human ear, the first sound wave and the second reverse sound wave are canceled to obtain the remaining noise after the cancellation;

[0029] The remaining noise after the cancellation is input into an adaptive filter, and the remaining noise after the cancellation is iterated to a minimum through an adaptive algorithm, and the remaining noise after the cancellation is input into an adaptive filter, and the remaining noise after the cancellation is iterated to a minimum through the adaptive algorithm of the adaptive filter.

[0030] In addition, to achieve the above purpose, the present application also provides a noise reduction system for vehicle audio compensation, the noise reduction system for vehicle audio compensation comprising:

[0031] Noise reduction system, music playback system and audio compensation module;

[0032] The noise reduction system is used to use the frequency signal of the engine speed as a reference signal, input it into the adaptive filter for iteration, control the adaptive filter to emit reverse sound waves to cancel the noise, and introduce a compensation signal into the noise reduction algorithm of the adaptive filter to cancel the music components that are mistakenly eliminated during noise reduction;

[0033] The music player is used to play music and output music track files;

[0034] The audio compensation module is used to calculate a compensation signal based on the audio media data and the engine signal data, and regulate the noise reduction module to perform output compensation.

[0035] In one embodiment, the noise reduction system includes: a control module, an engine module, and a full vehicle audio system;

[0036] The whole vehicle audio system includes a plurality of speakers and microphones for playing music or sounds;

[0037] The engine module is used to obtain engine speed characteristics and transmit them to the control module;

[0038] The control module is used to use the frequency signal of the engine speed as a reference signal, input it into the adaptive filter for iteration, control the adaptive filter to emit a reverse sound wave to cancel the noise, and introduce a compensation signal into the noise reduction algorithm of the adaptive filter to cancel the music components that are mistakenly eliminated during noise reduction.

[0039] In addition, to achieve the above-mentioned purpose, the present application also provides a noise reduction device for vehicle audio compensation, the device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the noise reduction method for vehicle audio compensation as described above.

[0040] In addition, to achieve the above-mentioned purpose, the present application also provides a storage medium, which is a computer-readable storage medium, and the computer-readable storage medium stores a program for implementing a noise reduction method for vehicle audio compensation. The program for implementing the noise reduction method for vehicle audio compensation is executed by a processor to implement the steps of the noise reduction method for vehicle audio compensation as described above.

[0041] The present application relates to the field of noise reduction technology, and in particular to a noise reduction method, system, device and storage medium for vehicle audio compensation. The noise reduction method for vehicle audio compensation includes: obtaining an audio file to be played and identifying the frequency characteristics of the audio file; obtaining an engine speed characteristic; obtaining a frequency range in which the frequency characteristics match the frequency corresponding to the engine speed characteristics, and performing order energy compensation on the audio file within the frequency range. The controller obtains the frequency characteristics and engine speed characteristics of the audio file, identifies the similar components of the frequency corresponding to the frequency characteristics of the audio file and the engine speed characteristics, calculates and controls the compensation moment and the compensation signal to perform energy compensation on the audio file with similar components, excludes the music component during noise reduction, so that the noise reduction is only for the target sound source and not for the music component, thereby avoiding the mistaken elimination of components in the music during noise reduction, resulting in a decrease in the listening experience of the music. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0044] Figure 1 A flowchart of a first embodiment of a noise reduction method for vehicle audio compensation provided by the present application;

[0045] Figure 2 A flowchart of a second embodiment of the noise reduction method for vehicle audio compensation provided by the present application;

[0046] Figure 3 A flowchart of a third embodiment of the noise reduction method for vehicle audio compensation provided in this application;

[0047] Figure 4 A diagram of a noise reduction algorithm in a noise reduction method for vehicle audio compensation in this application;

[0048] Figure 5 A schematic diagram of the structure of an embodiment of a noise reduction system for vehicle audio compensation provided by the present application;

[0049] Figure 6 The present invention is a schematic structural diagram of a noise reduction device for vehicle audio compensation in the hardware operating environment involved in the noise reduction method for vehicle audio compensation in the embodiment of the present application.

[0050] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0051] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0052] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0053] Some frequency components in music that are the same as engine order noise will be mistakenly eliminated. The common operating speed of a 4-cylinder engine is 1200-5000rpm, and the order frequency can cover the range of 40Hz-500Hz. In this range of music components, single-frequency drum beats, string instruments, and certain frequency harmonics of human voices will be affected. Mistaken elimination will weaken their energy, causing changes in subjective listening experience and affecting the sound quality effect.

[0054] The traditional method is to verify through real vehicle testing, perform EQ compensation on the frequency range that reduces the variation, and raise the amplitude within this frequency range. This approach is not accurate enough in terms of frequency, as it only needs to solve a single frequency while actually processing the entire frequency band. Secondly, the compensation amplitude cannot be quantified by a fixed value. It is affected by the convergence of the active noise reduction system, the noise level under different engine working conditions, the noise level at different seats, and the noise level of the music component.

[0055] The main solution of the embodiment of the present application is: obtain the audio file to be played and identify the frequency characteristics of the audio file; obtain the engine speed characteristics; obtain the frequency range that matches the frequency characteristics and the frequency corresponding to the engine speed characteristics, and perform order energy compensation on the audio file within the frequency range. The controller obtains the frequency characteristics of the audio file and the engine speed characteristics, identifies the similar components of the frequency corresponding to the frequency characteristics of the audio file and the engine speed characteristics, calculates the control compensation moment and the compensation signal to perform energy compensation on the audio file with similar components, excludes the music components during noise reduction, so that the noise reduction is only for the target sound source and not for the music components, thereby avoiding the mistaken elimination of components in the music during noise reduction, resulting in a decrease in the listening experience of the music.

[0056] It is understandable that the present application adopts compensation for noise reduction frequency points instead of EQ frequency bands, which is more accurate; secondly, the compensation method adopted by the present application is to directly introduce the compensation noise into the noise reduction algorithm for offset, rather than first reducing noise and then compensating the EQ response; finally, whether the present application compensates is dynamically controlled in real time according to the characteristics of the music, rather than just switching the mode by judging whether the noise reduction is turned on or off. In order to improve the accuracy of the frequency and amplitude of the compensation, the present application constantly corrects the real-time operating noise of the engine and the real-time components of the music to avoid erroneous elimination, and at the same time, there will be no over-compensation.

[0057] It should be noted that the execution subject of this embodiment can be a computing service device with data processing, network communication and program running functions, such as a tablet computer, a personal computer, a mobile phone, etc., or a noise reduction device for vehicle audio compensation that can achieve the above functions. The following takes the noise reduction controller as an example to illustrate this embodiment and the following embodiments.

[0058] Based on this, the embodiment of the present application provides a noise reduction method for vehicle audio compensation, referring to Figure 1 , Figure 1 This is a flow chart of a first embodiment of a noise reduction method for vehicle audio compensation according to the present application.

[0059] In this embodiment, the noise reduction method for vehicle audio compensation includes steps S10 to S30.

[0060] Step S10: Acquire the audio file to be played, and identify the frequency characteristics of the audio file.

[0061] It should be noted that the controller is connected to the music playing system to obtain the audio file to be played.

[0062] Step S20: Obtain engine speed characteristics.

[0063] It should be noted that the speed of the actual engine is related to many factors, and the engine speed is different in different working modes. For example, if the engine of a REV model is only used for charging, it usually maintains a fixed speed. If the engine of a REV model participates in power output, the speed is related to the vehicle speed pedal gear position MAP, etc.

[0064] It is understandable that, for example, when charging at a constant speed, the engine speed is a fixed value. The possible charging speeds of the engine of a certain vehicle model are 1800rpm, 2100rpm, 260rpm, and 3500rpm.

[0065] Optionally, if it is a dynamic speed condition, short-term prediction can also be made based on the user's driving habits and road conditions. The prediction method can be a variety of deep learning prediction model algorithms.

[0066] Step S30: Acquire a frequency range in which the frequency characteristic matches the frequency corresponding to the engine speed characteristic, and perform order energy compensation on the audio file within the frequency range.

[0067] It should be noted that according to different audio files, frequency features are pre-identified, and possible frequency components in the features are identified and extracted to form key features such as frequency, time, amplitude, etc. for compensation judgment. At the same time, the frequency corresponding to the current (or predicted) engine speed is compared to determine whether compensation is turned on. The specific similarity features are not fixed and are determined in real time according to different sound sources and noise reduction conditions. After identifying the frequency of the audio file that is eliminated during noise reduction, the compensation signal is calculated and directly introduced into the noise reduction algorithm for offset.

[0068] It can be understood that the method for determining the frequency range may include characteristic duration, characteristic frequency variation range, peak energy threshold, etc.

[0069] In this embodiment, the frequency characteristics of the audio file and the frequency components corresponding to the engine speed characteristics are identified, and the components of the frequency characteristics of the audio file are excluded during noise reduction, so that the noise reduction is only for the target sound source and not for the music components, thereby avoiding the mistaken elimination of components in the music during noise reduction, resulting in a decrease in the listening experience of the music. At the same time, this application takes into account the different characteristics of different music, and dynamically matches and identifies the frequency corresponding to the current engine speed characteristics and the frequency characteristics of the audio file, rather than using fixed sound frequency band compensation, thereby enhancing the accuracy of the compensated sound frequency.

[0070] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can be referred to the above introduction, and will not be repeated in the following. Figure 2 , Figure 2 This is a flow chart of the second embodiment of the noise reduction method for vehicle audio compensation provided by the present application. In the steps, the noise reduction method for vehicle audio compensation includes:

[0071] Step S201: Acquire an audio file to be played, and acquire music feature data of the audio file.

[0072] It should be noted that the audio file to be played is obtained to obtain the music feature data: sampling rate, bit depth, number of channels, time domain data, etc. Sampling rate: used to convert the number of data points corresponding to time, such as a sampling rate of 48kHz, then the 1s moment of the audio corresponds to the 48000th data point; bit depth: used to determine the amplitude range of the audio and convert the sound energy; number of channels: to determine whether the sound source is mono, dual-channel, or multi-channel, it is necessary to identify the characteristics of different channel data.

[0073] Step S202: Perform Fourier transform on the music feature data to obtain the frequency features of the audio file.

[0074] It should be noted that the frequency domain features of the data are obtained by Fourier transforming the time domain data, and the time-frequency characteristics of the music are analyzed to identify the peaks with prominent features in the range of 40-500Hz, and the following music feature data are obtained:

[0075] The number of sampling points at the time of appearance is N1, the number of sampling points at the time of disappearance is N2, the frequency at the time of appearance is f1, the frequency at the time of disappearance is f2, and the peak energy Ga of appearance.

[0076] Step S203: Obtain the noise reduction order frequency corresponding to the engine speed.

[0077] It should be noted that when the engine is charged at a fixed speed, the charging speed is 1800rpm, 2100rpm, 2600rpm, and 3500rpm. The 2nd, 4th, and 6th order frequencies corresponding to these four speed points are fno2, fno4, and fno6. Among them, the noise reduction order frequency corresponding to the engine speed is x(n).

[0078] Step S204: determining a frequency range that needs to be compensated in the frequency characteristics according to the noise reduction order frequency.

[0079] It should be noted that the noise reduction order frequency x(n) corresponding to the engine speed is compared with the frequency characteristics of the audio file to determine whether they match, and the matching frequency range is the frequency range that needs to be compensated. Among them, determining the frequency range that matches the frequency characteristics with the frequency x(n) corresponding to the engine speed characteristics includes the following methods:

[0080] Whether the characteristic duration Δt=t2-t1 exceeds the judgment threshold t*; whether the characteristic frequency change range Δf=f2-f1 exceeds the judgment threshold f*; whether the peak energy Ga exceeds the judgment threshold Ga*; and the weight judgment of the above features, etc.

[0081] It is understandable that when the duration Δt is too small or Δf changes too quickly, which is much smaller than the response time of the ANC system, or the peak energy is significantly smaller than the engine noise energy, it is considered that such peak characteristics can be ignored and no processing is done, and the characteristic frequency within the threshold range is identified as the frequency range that needs to be compensated (the t* and f* thresholds are set according to the convergence performance speed of the active noise reduction adaptive system, and the Ga* threshold is set according to the noise reduction target value of the adaptive system).

[0082] Finally, for a played track, k features to be compensated are identified, corresponding to the parameters N1(k), N2(k), f1(k), f2(k), and Ga(k).

[0083] In this embodiment, the music feature data of the audio file is obtained, including the number of sampling points N1 at the time of appearance, the number of sampling points N2 at the time of disappearance, the frequency f1 at the time of appearance, the frequency f2 at the time of disappearance, and the peak energy Ga at the time of appearance; the noise reduction order frequency x(n) corresponding to the engine speed is obtained, and the music feature data of the audio file is used to determine whether x(n) exists, and the characteristic duration of x(n) in the audio file, the characteristic frequency variation range of the appearance and disappearance of x(n) and the peak energy of the appearance of x(n) are combined to determine whether they match. The matching frequency range is the frequency range that needs to be compensated. If there is no frequency range that matches x(n) in the audio file, the noise reduction system does not interfere with the audio and does not need to compensate the audio. The frequency feature and x(n) are corrected at all times, and the frequency range for judging whether the frequency feature matches x(n) also changes in real time, thereby improving the accuracy of the compensated frequency and amplitude.

[0084] Based on the first embodiment and / or the second embodiment of the present application, in the third embodiment of the present application, the same or similar contents as those of the above-mentioned first and second embodiments can refer to the above introduction, and will not be repeated later. Figure 3 and Figure 4 , Figure 3 This is a flow chart of the third embodiment of the noise reduction method for vehicle audio compensation provided by this application. Figure 4 It is a noise reduction algorithm in the noise reduction method for vehicle audio compensation.

[0085] Step S301: calculating a compensation signal in the frequency range that needs to be compensated by using the transfer function.

[0086] Before step S301, the method further includes:

[0087] Step S300: measuring the transfer function from the corresponding audio frequency emitted by each speaker to the human ear.

[0088] It should be noted that when the sound source file is broadcasted through the sound system and transmitted to the human ear, it will undergo a series of changes, including changes in the tuning algorithm, hardware circuit transmission delay and amplification, and the physical process of the sound being transmitted through the speaker to the human ear. These processes will cause the time phase of the sound to change based on the original audio, and the sound amplitude at different frequencies to change. Therefore, it is necessary to measure the transfer function H of this part. m , considering the influence of its amplitude and phase, the audio characteristic parameters are compensated, and the compensated sound parameters are N1ˋ(k), N2ˋ(k), and Gaˋ(k).

[0089] It is understandable that there are multiple speakers in the car that emit sound frequencies close to the active noise reduction frequency, such as the bass speakers and subwoofer speakers in the four doors, and the transmission function of the corresponding audio from each speaker to the human ear is measured separately. m1 (z), H m1 (z),…,H m1 (z), according to the transfer function of each transfer path, the sound parameters N1ˋ1(k), N2ˋ1(k), Gaˋ1(k), …, N1ˋn(k), N2ˋn(k), Gaˋn(k) after compensation of each path are calculated respectively.

[0090] Step S302: input the compensation signal to an adaptive filter, and output a first sound wave at an output end of the adaptive filter by iteratively controlling the weight coefficients of the adaptive filter.

[0091] It should be noted that, in the traditional noise reduction algorithm, taking the LMS algorithm as an example, the noise emitted by the engine sound source is transmitted to the human ear d(n), which is the target sound for noise reduction. At the same time, the current engine speed is converted into frequency as x(n), and input into the adaptive filter. The control weight coefficients w11(n) and w2(n) are iteratively generated to generate the reverse sound wave y(n), which is offset with d(n). The remaining noise after the offset is e(n), which is also input into the adaptive algorithm as the residual noise, that is, e(n)=d(n)-y(n); by adapting, e(n) is iterated to the minimum, thus achieving the purpose of noise reduction. The influence of music interference sound dˋ(n) is not considered in the process. The actual situation is e(n)=d(n)+dˋ(n)-y(n); the adaptively generated y(n) offsets d(n)+dˋ(n), and the traditional noise reduction also eliminates the music interference sound dˋ(n). The music interference sound is the frequency range that matches x(n) in the frequency characteristics of the audio file. The traditional noise reduction algorithm eliminates the frequency in the music that is the same as x(n), affecting the sound quality of the music.

[0092] It can be understood that after determining and obtaining the frequency range that matches the frequency characteristic with the frequency x(n) corresponding to the engine speed characteristic, the compensation signal yˋˋ(n) of the frequency range is calculated through the transfer function, and the compensation signal yˋˋ(n) is input into the adaptive filter, and the compensation signal yˋˋ(n) is introduced into the calculation of e(n) and the first sound wave is output at the output end of the adaptive filter by iteratively controlling the weight coefficients of the adaptive filter.

[0093] Step S303: performing order energy compensation on the frequency range by using the first sound wave.

[0094] It should be noted that the first sound wave is superimposed on the noise emitted by the engine sound source and transmitted to the human ear d(n), the music interference sound dˋ(n) and the iteratively generated reverse sound wave y(n), to achieve:

[0095] e(n)=d(n)+dˋ(n)-y(n)-yˋˋ(n), eliminating the influence of dˋ(n), that is, active noise reduction will not additionally reduce the frequency components in the music.

[0096] Step S331: convert the current engine speed into frequency data and input it into the adaptive filter, and output the second reverse sound wave at the output end of the adaptive filter by controlling the weight coefficient of the adaptive filter to iterate.

[0097] It should be noted that, in this embodiment, the noise emitted by the engine sound source is transmitted to the human ear as d(n), which is the target sound for noise reduction. At the same time, the current speed of the engine is converted into a frequency as x(n) and input into the adaptive filter. The control weight coefficients w11(n) and w2(n) are iteratively used to generate the reverse sound wave y(n).

[0098] Step S332: canceling the sound transmitted to the human ear, the first sound wave and the second reverse sound wave to obtain the remaining noise after the cancellation.

[0099] It should be noted that the compensation signal yˋˋ(n) is introduced into the adaptive filter to achieve

[0100] e(n)=d(n)+dˋ(n)-y(n)-yˋˋ(n)

[0101] The sound transmitted to the human ear includes the noise emitted by the engine sound source transmitted to the human ear d(n) and the music interference sound dˋ(n). The remaining noise after cancellation is e(n), which is also input into the adaptive algorithm as residual noise.

[0102] Step S333: input the remaining noise after cancellation into the adaptive filter, and iterate the remaining noise after cancellation to a minimum through the adaptive algorithm, and input the remaining noise after cancellation into the adaptive filter, and iterate the remaining noise after cancellation to a minimum through the adaptive algorithm of the adaptive filter.

[0103] It can be understood that the method of the present application can realize automatic control of whether active noise reduction is needed at every moment according to the frequency characteristics of the music, and perform noise reduction and interference elimination control according to the signals in the music, so as to achieve the purpose of not eliminating the components in the music at any time.

[0104] In this embodiment, when the frequency x(n) corresponding to the generator speed matches the frequency characteristics of the audio file, the frequency characteristics of the audio file are compensated, and a compensation signal is calculated through a transfer function, and the compensation signal is introduced into an adaptive filter. The first sound wave is output at the output end of the adaptive filter by controlling the weight coefficient of the adaptive filter to iteratively output the first sound wave, and the first sound wave performs order energy compensation on the frequency range of the audio file. The frequency signal of the engine speed generates a second reverse wave in the adaptive filter, and the noise emitted by the engine sound source is transmitted to the human ear d(n), the music interference sound dˋ(n), the first sound wave and the second reverse wave are offset, and the remaining noise after the offset is iterated to a minimum.

[0105] Reference Figure 5 , Figure 5 This is a module diagram of the first embodiment of the noise reduction system for vehicle audio compensation proposed by the present invention. Figure 5 A first embodiment of the noise reduction system for vehicle audio compensation of the present invention is provided.

[0106] The noise reduction system for vehicle audio compensation includes: a noise reduction system 10, a music player system 20 and an audio compensation module 30; the noise reduction system 10 is used to use the frequency signal of the engine speed as a reference signal, input it into the adaptive filter for iteration, control the adaptive filter to emit a reverse sound wave to cancel the noise, and introduce the compensation signal into the noise reduction algorithm of the adaptive filter to cancel the music components mistakenly eliminated during noise reduction; the music player 20 is used to play music and output music track files; the audio compensation module 30 is used to calculate the compensation signal according to the audio media data and the engine signal data, and adjust the noise reduction module to output compensation.

[0107] It should be noted that the noise reduction system is a traditional noise reduction system, including a control module, an error microphone, a speaker, an engine module, a music playback system for obtaining an audio file, and an audio compensation module 30 for calculating a compensation signal according to the frequency characteristics of the audio file and the engine speed signal, and controlling the noise reduction system for compensation. The audio compensation module 30 determines whether the frequency characteristics match the frequency corresponding to the engine speed characteristics, obtains a matching frequency range, calculates the compensation signal of the frequency range through a transfer function, and performs order energy compensation on the frequency range of the audio file.

[0108] It can be understood that the noise emitted by the engine sound source is transmitted to the human ear d(n), which is the target sound of noise reduction. The noise reduction system 10 converts the current engine speed into a frequency as x(n), and inputs it to the adaptive filter. The control weight coefficients w11(n) and w2(n) are iteratively generated to generate a reverse sound wave y(n). The noise reduction system receives the compensation signal yˋˋ(n) sent by the audio compensation module 30. The noise emitted by the engine sound source is transmitted to the human ear d(n), the music interference sound dˋ(n), the first sound wave and the second reverse wave are offset. The remaining noise after the offset is iterated to the minimum, so that active noise reduction will not additionally reduce the frequency components in the music.

[0109] The noise reduction system includes: a control module, an engine module and a full-vehicle audio system; the full-vehicle audio system includes multiple speakers and microphones for playing music or sounds; the engine module is used to obtain the engine speed characteristics and transmit them to the control module; the control module is used to use the frequency signal of the engine speed as a reference signal, input it into the adaptive filter for iteration, control the adaptive filter to emit reverse sound waves to cancel noise, and introduce the compensation signal into the noise reduction algorithm of the adaptive filter to cancel the music components that are mistakenly eliminated during noise reduction.

[0110] It should be noted that the audio compensation module 30 considers the whole vehicle audio system, including the transmission of multiple channel speakers to the human ear, and the influence of different transfer functions of the entire path caused by tuning algorithms, hardware differences, and transmission path differences, and calculates and controls the compensation time and compensation energy respectively, and inputs them into the noise reduction system to ensure the accuracy of the compensation of the error noise at the human ear. For example, the influence of the door speaker tuning hardware parameters (the low-frequency component emitted starts from 60Hz, and no compensation is required before 60Hz), the sound emitted passes through the interior space of the car to the human ear (delay phase, compensation of energy attenuation), the tuning of the subwoofer in the trunk (starting from 40Hz), passes through the interior space of the car to the human ear (delay phase, energy attenuation, etc.), and considers the influence of all speaker paths that emit similar frequencies (from sound source-tuning-transmission process) and compensates them separately.

[0111] It can be understood that the noise reduction system for vehicle audio compensation is based on the traditional engine active noise reduction system. By adding an automatic control method, it eliminates similar feature interference (in the music component) other than engine noise, and achieves noise reduction only for engine noise, avoiding additional elimination of other components (such as loss of components caused by music, which reduces the hearing experience). No additional hardware is added, and only the software algorithm level is upgraded.

[0112] In this embodiment, the music player outputs an audio file, the engine module outputs the engine speed, the audio compensation module is used to measure and output the transfer function of each speaker, the audio compensation module is used to calculate a compensation signal based on the audio file, the engine speed and the transfer function, the control module inputs the compensation signal and the engine speed to the adaptive filter, and the control module controls the adaptive filter to eliminate noise.

[0113] The present application provides a noise reduction device for vehicle audio compensation, and the noise reduction device for vehicle audio compensation includes: at least one processor; and a memory connected to the at least one processor in communication; wherein the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the noise reduction method for vehicle audio compensation in the above-mentioned embodiment 1.

[0114] Reference below Figure 6 , which shows a schematic diagram of the structure of a noise reduction device for vehicle audio compensation suitable for implementing the embodiment of the present application. The noise reduction device for vehicle audio compensation in the embodiment of the present application may include but is not limited to mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle terminals (such as vehicle navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 6 The noise reduction device shown for vehicle audio compensation is merely an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0115] like Figure 6As shown, the noise reduction device for vehicle audio compensation may include a processing device 1001 (e.g., a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. Various programs and data required for the operation of the noise reduction device for vehicle audio compensation are also stored in the RAM 1004. The processing device 1001, the ROM 1002, and the RAM 1004 are connected to each other via a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems may be connected to the I / O interface 1006: input devices 1007 including, for example, a touch screen, a touchpad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; storage devices 1003 including, for example, a magnetic tape, a hard disk, etc.; and communication devices 1009. The communication device 1009 may allow the noise reduction device for vehicle audio compensation to communicate wirelessly or wired with other devices to exchange data. Although the figure shows a noise reduction device for vehicle audio compensation with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems may be implemented or have instead.

[0116] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0117] The noise reduction device for vehicle audio compensation provided by the present application adopts the noise reduction method for vehicle audio compensation in the above embodiment, which can solve the technical problem that the components in the audio media music are mistakenly eliminated and the music listening experience is deteriorated. Compared with the prior art, the beneficial effects of the noise reduction device for vehicle audio compensation provided by the present application are the same as the beneficial effects of the noise reduction method for vehicle audio compensation provided by the above embodiment, and the other technical features of the noise reduction device for vehicle audio compensation are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0118] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0119] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0120] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, computer programs) stored thereon, and the computer-readable program instructions are used to execute the noise reduction method for vehicle audio compensation in the above-mentioned embodiment.

[0121] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination of the above.

[0122] The computer-readable storage medium may be included in the noise reduction device for vehicle audio compensation; or may exist independently without being assembled into the noise reduction device for vehicle audio compensation.

[0123] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0124] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0125] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0126] The readable storage medium provided by the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned noise reduction method for vehicle audio compensation, and can solve the technical problem that components in audio media music are mistakenly eliminated and the music listening experience is deteriorated. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided by the present application are the same as the beneficial effects of the noise reduction method for vehicle audio compensation provided by the above-mentioned embodiment, and will not be repeated here.

[0127] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A noise reduction method for vehicle audio compensation, characterized in that: The noise reduction method for vehicle audio compensation includes: Obtain an audio file to be played, and identify the frequency characteristics of the audio file; Obtain engine speed characteristics; A frequency range in which the frequency characteristic matches the frequency corresponding to the engine speed characteristic is obtained, and order energy compensation is performed on the audio file within the frequency range.

2. The noise reduction method for vehicle audio compensation according to claim 1, characterized in that: The step of obtaining the audio file to be played and identifying the frequency characteristics of the audio file includes: Acquire an audio file to be played, and acquire music feature data of the audio file; Performing Fourier transform on the music feature data to obtain the frequency feature of the audio file.

3. The noise reduction method for vehicle audio compensation as claimed in claim 2, characterized in that: The acquiring a frequency range matching the frequency characteristic with the frequency corresponding to the engine speed characteristic, and performing order energy compensation on the audio file within the frequency range, comprises: Obtaining a noise reduction order frequency corresponding to the engine speed; Determining a frequency range that needs to be compensated in the frequency characteristic according to the noise reduction order frequency; Perform order energy compensation on the audio file within the frequency range.

4. The noise reduction method for vehicle audio compensation as claimed in claim 3, characterized in that: The performing order energy compensation on the audio file within the frequency range comprises: Measure the transfer function from the corresponding audio frequency emitted by each speaker to the human ear; Calculating a compensation signal of the frequency range that needs to be compensated by using the transfer function; The order energy compensation is performed on the frequency range by using the compensation signal.

5. The noise reduction method for vehicle audio compensation as claimed in claim 4, characterized in that: The performing order energy compensation on the frequency range by using the compensation signal comprises: Inputting the compensation signal to an adaptive filter, and outputting a first sound wave at an output end of the adaptive filter by iteratively controlling the weight coefficients of the adaptive filter; The order energy compensation is performed on the frequency range by using the first sound wave.

6. The noise reduction method for vehicle audio compensation according to claim 1, characterized in that: After the step of performing order energy compensation on the frequency range by using the first sound wave, the method further includes: Convert the current speed of the engine into frequency data and input it into the adaptive filter, and output a second reverse sound wave at the output end of the adaptive filter by controlling the weight coefficient iteration of the adaptive filter; The sound transmitted to the human ear, the first sound wave and the second reverse sound wave are canceled to obtain the remaining noise after the cancellation; The remaining noise after the cancellation is input into an adaptive filter, and the remaining noise after the cancellation is iterated to a minimum through an adaptive algorithm, and the remaining noise after the cancellation is input into an adaptive filter, and the remaining noise after the cancellation is iterated to a minimum through the adaptive algorithm of the adaptive filter.

7. A noise reduction system for vehicle audio compensation, characterized in that: The noise reduction method for vehicle audio compensation is applied to the noise reduction system for vehicle audio compensation, and the noise reduction system for vehicle audio compensation includes: a noise reduction system, a music playing system and an audio compensation module; The noise reduction system is used to use the frequency signal of the engine speed as a reference signal, input it into the adaptive filter for iteration, control the adaptive filter to emit reverse sound waves to cancel the noise, and introduce a compensation signal into the noise reduction algorithm of the adaptive filter to cancel the music components that are mistakenly eliminated during noise reduction; The music player is used to play music and output music track files; The audio compensation module is used to calculate a compensation signal based on the audio media data and the engine signal data, and regulate the noise reduction module to perform output compensation.

8. The noise reduction system for vehicle audio compensation as claimed in claim 7, characterized in that: The noise reduction system for automatic compensation of vehicle audio sound effects comprises: a control module, an engine module and a whole vehicle audio system; The whole vehicle audio system includes a plurality of speakers and microphones for playing music or sounds; The engine module is used to obtain engine speed characteristics and transmit them to the control module; The control module is used to use the frequency signal of the engine speed as a reference signal, input it into the adaptive filter for iteration, control the adaptive filter to emit a reverse sound wave to cancel the noise, and introduce a compensation signal into the noise reduction algorithm of the adaptive filter to cancel the music components that are mistakenly eliminated during noise reduction.

9. A noise reduction device for vehicle audio compensation, characterized in that: The device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the noise reduction method for vehicle audio compensation according to any one of claims 1 to 6.

10. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the noise reduction method for vehicle audio compensation as described in any one of claims 1 to 6 are implemented.

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