Sound equipment noise reduction system for noise reduction processing of closed space and sound equipment

Abstract

The invention relates to the technical field of noise reduction sound equipment, and discloses a sound equipment noise reduction system for closed space noise reduction processing, which comprises a signal processing module, a feedback adjustment module, an audio decoding module, a data storage module and an audio control module, and the signal processing module is used for collecting a spectrum characteristic abnormal coefficient, reverberation time and a ratio of energy of direct sound to reverberation sound between the sound waves collected by the noise detection sensor and the audios fed back by the audio decoding module. Different active noise reduction effects are applied by judging whether the sound equipment is in the closed space or not, when the sound equipment is in the closed environment, reverse sound waves of environmental noise and loudspeaker audio reverberation are applied to suppress the noise, and when the sound equipment is in the open environment, only the reverse sound waves of the environmental noise are applied to suppress the noise. According to the method, the echo of the sound equipment during indoor playing can be effectively reduced, and the problem that sound playing is dull due to the fact that audio echo reverse sound waves are additionally added during outdoor playing is also avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of noise reduction sound, and in particular to a sound noise reduction system and a sound system for noise reduction processing in a closed space. Background Art

[0002] Sound refers to all sounds other than human speech and music, including sounds from the natural environment, animals, tools, and human movements. Sound mainly includes functions, peripheral equipment (including compressors, effectors, equalizers, VCDs, DVDs, etc.), speakers (sound boxes, speakers), mixers, microphones, display devices, etc. Among them, speakers are sound output devices, speakers, subwoofers, etc.

[0003] The existing patent discloses an audio system that can eliminate environmental noise and a noise reduction method for a speaker system (publication number CN107948871A). The audio system includes: an audio receiver, an audio processor, at least two speakers, and a noise reduction module. The noise reduction module includes a sound collection module, a noise judgment module, and a noise reduction circuit. The sound collection module is used to collect environmental sound signals and output them to the noise judgment module. The noise judgment module judges the sound signals collected in the sound collection module to determine whether they are noise.

[0004] Since there will be obvious reverberation when the speakers are played in a closed space, the reverberation needs to be considered as the object of noise reduction when using active noise reduction in a closed space, while when playing in an open environment, only external noise needs to be considered as the object of noise reduction. The technology disclosed in the above-mentioned existing patents only solves the problem of judging noise, determining whether it is noise and suppressing it. However, if it is the reverberation of the audio, and because the reverberation of the audio is very similar to the audio, it is often difficult to judge it as noise and cannot be suppressed. At this time, there will be obvious reverberation when playing in a closed space. Summary of the invention

[0005] The main technical problem solved by the present invention is to provide an audio noise reduction system and an audio system for noise reduction processing in a closed space, which solves the problems in the above-mentioned background technology.

[0006] To solve the above technical problems, according to one aspect of the present invention, more specifically, an audio noise reduction system for closed space noise reduction processing is provided, characterized in that it comprises: a signal processing module, a feedback adjustment module, an audio decoding module, a data storage module, an audio control module, a noise detection sensor and a speaker, wherein the noise detection sensor specifically comprises a main noise sensor and an auxiliary noise sensor;

[0007] The signal processing module determines whether the sound is in a closed space based on the frequency spectrum characteristic anomaly coefficient, reverberation time, and the ratio of direct sound to reverberation sound energy between the sound wave collected by the noise detection sensor and the audio feedback from the audio decoding module;

[0008] The feedback adjustment module is used to actively apply a reverse sound wave signal of ambient noise or speaker audio reverberation to the audio decoding module according to whether the speaker is placed in a closed space;

[0009] The audio decoding module is used to parse the audio file stored in the data storage module to control the speaker playing, and also applies the reverse sound wave of the ambient noise or the speaker audio reverberation to suppress the noise according to the feedback of the feedback adjustment module.

[0010] Furthermore, the audio control module is used to adjust the gain, balance and volume of the audio signal.

[0011] Furthermore, the data storage module is used to store audio files.

[0012] Furthermore, the signal processing module determines whether the sound is in a closed space based on the frequency spectrum characteristic anomaly coefficient, reverberation time, and the ratio of direct sound to reverberation sound energy between the sound waves collected by the noise detection sensor and the audio emitted by the speaker. Then:

[0013] ;

[0014] In the formula, represents the probability coefficient of the sound being in a closed space, It represents the frequency spectrum characteristic anomaly coefficient between the sound waves collected by the noise detection sensor and the audio emitted by the speaker. It represents the time required for the sound from the speaker to decay from the initial peak to the background noise level. It represents the ratio of direct sound to reverberant sound energy.

[0015] Furthermore, the signal processing module determines the frequency spectrum characteristic anomaly coefficient between the sound wave collected by the noise detection sensor and the audio feedback from the speaker according to the high-frequency attenuation of the audio emitted by the secondary collection speaker and the proportion of intermittent or continuous low-frequency noise, which is:

[0016] ;

[0017] In the formula, It represents the frequency spectrum characteristic anomaly coefficient between the sound waves collected by the noise detection sensor and the audio emitted by the speaker. Indicates the high-frequency attenuation of the audio emitted by the secondary collection speaker. Indicates the proportion of intermittent or continuous low-frequency noise.

[0018] Furthermore, when When , it means that the speaker is in a closed space, and the noise can be suppressed by the reverse sound waves of the ambient noise and the speaker audio reverberation;

[0019] when , it means that the speaker is not in a closed space, and the noise can be suppressed only by the reverse sound waves of the ambient noise.

[0020] Furthermore, the main noise sensor is used to collect environmental noise outside the audio system.

[0021] Furthermore, the auxiliary noise sensor is used to collect the vibration of the sound housing and the sound emitted by the speaker.

[0022] A speaker used for noise reduction in a closed space comprises a hardware board for carrying a speaker noise reduction system.

[0023] Beneficial effects:

[0024] 1. The present invention can simply and efficiently determine whether the sound is in a closed space by using a signal processing module based on the spectral characteristic anomaly coefficient between the sound waves collected by the noise detection sensor and the audio emitted by the speaker, the reverberation time, and the ratio of the direct sound to the reverberation sound energy.

[0025] 2. The present invention applies different active noise reduction effects by judging whether the speaker is in a closed space. When the speaker is in a closed environment, the reverse sound waves of ambient noise and speaker audio reverberation are applied to suppress the noise. When the speaker is in an open environment, only the reverse sound waves of ambient noise are applied to suppress the noise. This method can effectively reduce the reverberation of the speaker when it is played indoors, and avoid the problem of dull playback sound caused by additional audio reverberation reverse sound waves when it is played outdoors. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the internal structure of the speaker in the present invention;

[0027] Figure 2 is a schematic diagram of the audio noise reduction system of the present invention;

[0028] Figure 3 It is a schematic diagram of the sound system in the present invention. DETAILED DESCRIPTION

[0029] In order to make the technical solution of the present invention clearer, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] Example 1

[0031] like Figure 1, 3 As shown, according to one aspect of the present invention, a sound system for noise reduction in a closed space is provided, including a hardware board for carrying a sound system noise reduction system. The noise detection sensor specifically includes a main noise sensor and a secondary noise sensor. The main noise sensor is used to collect environmental noise outside the sound system. The secondary noise sensor is used to collect vibrations of the sound system housing and sounds emitted by the speaker.

[0032] Example 2

[0033] like Figure 1 , 2 As shown, a sound noise reduction system for closed space noise reduction processing includes a signal processing module, a feedback adjustment module, an audio decoding module, a data storage module and an audio control module; the signal processing module determines whether the sound is in a closed space according to the spectral characteristic abnormality coefficient, reverberation time, and the ratio of direct sound to reverberation sound energy between the sound wave collected by the noise detection sensor and the audio feedback from the audio decoding module; the feedback adjustment module is used to actively apply the reverse sound wave signal of the ambient noise or the audio reverberation of the speaker to the audio decoding module according to whether the sound is placed in a closed space; the audio decoding module is used to parse the audio file stored in the data storage module to control the speaker playback, and also apply the reverse sound wave of the ambient noise or the audio reverberation of the speaker to suppress the noise according to the feedback of the feedback adjustment module. The audio control module is used to adjust the gain, balance and volume of the audio signal. The data storage module is used to store audio files. By determining whether the speaker is in a closed space, different active noise reduction effects are applied. When the speaker is in a closed environment, the reverse sound waves of ambient noise and speaker audio reverberation are applied to suppress the noise. When the speaker is in an open environment, only the reverse sound waves of ambient noise are applied to suppress the noise. This method can effectively reduce the reverberation of the speaker when it is played indoors, and avoid the problem of dull playback sound caused by increasing audio reverberation reverse sound waves when playing outdoors.

[0034] Example 3

[0035] like Figure 2 As shown, the signal processing module determines whether the sound is in a closed space based on the spectral characteristic anomaly coefficient, reverberation time, and the ratio of direct sound to reverberation sound energy between the sound waves collected by the noise detection sensor and the audio emitted by the speaker. Then:

[0036] ;

[0037] In the formula, represents the probability coefficient of the sound being in a closed space, It represents the frequency spectrum characteristic anomaly coefficient between the sound waves collected by the noise detection sensor and the audio emitted by the speaker. It represents the time required for the sound from the speaker to decay from the initial peak to the background noise level. It represents the ratio of direct sound to reverberant sound energy.

[0038] The signal processing module determines the spectral characteristic anomaly coefficient between the sound waves collected by the noise detection sensor and the audio feedback from the speaker based on the high-frequency attenuation of the audio emitted by the secondary collection speaker and the proportion of intermittent or continuous low-frequency noise, which are:

[0039] ;

[0040] In the formula, It represents the frequency spectrum characteristic anomaly coefficient between the sound waves collected by the noise detection sensor and the audio emitted by the speaker. Indicates the high-frequency attenuation of the audio emitted by the secondary collection speaker. Indicates the proportion of intermittent or continuous low-frequency noise.

[0041] The probability coefficient of any primary sound being in a closed space is calculated. The high-frequency attenuation of the audio emitted by the secondary collection speaker is taken as (Unit: dB, high frequency attenuation = ,in is the intensity of the audio coming out of the speaker, is the strength of the reverberant audio).

[0042] The proportion of intermittent or continuous low-frequency noise is (c = the duration of collecting 20-200Hz noise ÷ the total duration of the collected noise). Then we have:

[0043] ;

[0044] From the above calculation, we can know that during the calculation of the probability coefficient of the sound being in a closed space, the frequency spectrum characteristic anomaly coefficient between the sound wave collected by the noise detection sensor and the audio emitted by the speaker is , where the larger the value of m is, the greater the probability that the speaker is in a closed space.

[0045] Furthermore, in the process of calculating the probability coefficient of the sound being in a closed space, the time required for the sound emitted by the speaker to decay from the initial peak to the background noise level is taken as (Unit: s, recording the time required for the speaker to emit a 60dB audio frequency and the sound received by the noise detection sensor to decrease to the background noise level). (Energy ratio = (direct sound energy ÷ reverberation sound energy)), then:

[0046] ;

[0047] From the above calculation, we can know that the probability coefficient of the sound system being in a closed space is , then the speaker is in a closed space, and the noise can be suppressed by the reverse sound waves of ambient noise and speaker audio reverberation. And compare multiple sets of data:

[0048] Table 1 Parameters of some implementation data and the spatial status of the sound system

[0049]

[0050] From the data in Table 1 above, we can see that when the sample data tends to be infinite, the probability coefficient g will be used as a dividing line to determine whether the sound is in a closed space. When , it means that the speaker is in a closed space, and the noise can be suppressed by the reverse sound waves of the ambient noise and the speaker audio reverberation; when , it means that the speaker is not in a closed space, and the noise can be suppressed only by the reverse sound waves of the ambient noise.

[0051] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An acoustic noise reduction system for noise reduction in a closed space, characterized in that: include: A signal processing module, a feedback adjustment module, an audio decoding module, a data storage module, an audio control module, a noise detection sensor and a speaker, wherein the noise detection sensor specifically includes a main noise sensor and an auxiliary noise sensor; The signal processing module determines whether the sound is in a closed space based on the frequency spectrum characteristic anomaly coefficient, reverberation time, and the ratio of direct sound to reverberation sound energy between the sound wave collected by the noise detection sensor and the audio feedback from the audio decoding module; The feedback adjustment module is used to actively apply a reverse sound wave signal of ambient noise or speaker audio reverberation to the audio decoding module according to whether the speaker is placed in a closed space; The audio decoding module is used to parse the audio file stored in the data storage module to control the speaker playing, and also applies the reverse sound wave of the ambient noise or the speaker audio reverberation to suppress the noise according to the feedback of the feedback adjustment module.

2. The acoustic noise reduction system for closed space noise reduction according to claim 1, characterized in that: The audio control module is used to adjust the gain, balance and volume of the audio signal.

3. The acoustic noise reduction system for closed space noise reduction according to claim 1, characterized in that: The data storage module is used to store audio files.

4. The acoustic noise reduction system for closed space noise reduction according to claim 1, characterized in that: The signal processing module determines whether the sound is in a closed space based on the spectral characteristic anomaly coefficient, reverberation time, and the ratio of direct sound to reverberation sound energy between the sound waves collected by the noise detection sensor and the audio emitted by the speaker. Then: ； In the formula, represents the probability coefficient of the sound being in a closed space, It represents the frequency spectrum characteristic anomaly coefficient between the sound waves collected by the noise detection sensor and the audio emitted by the speaker. It represents the time required for the sound from the speaker to decay from the initial peak to the background noise level. It represents the ratio of direct sound to reverberant sound energy.

5. The acoustic noise reduction system for closed space noise reduction according to claim 4, characterized in that: The signal processing module determines the frequency spectrum characteristic anomaly coefficient between the sound wave collected by the noise detection sensor and the audio feedback from the speaker according to the high-frequency attenuation of the audio emitted by the secondary collection speaker and the proportion of intermittent or continuous low-frequency noise, which is: ； In the formula, It represents the frequency spectrum characteristic anomaly coefficient between the sound waves collected by the noise detection sensor and the audio emitted by the speaker. Indicates the high-frequency attenuation of the audio emitted by the secondary collection speaker. Indicates the proportion of intermittent or continuous low-frequency noise.

6. The acoustic noise reduction system for closed space noise reduction according to claim 4, characterized in that: when When , it means that the speaker is in a closed space, and the noise can be suppressed by the reverse sound waves of the ambient noise and the speaker audio reverberation; when , it means that the speaker is not in a closed space, and the noise can be suppressed only by the reverse sound waves of the ambient noise.

7. The acoustic noise reduction system for closed space noise reduction according to claim 1, characterized in that: The main noise sensor is used to collect environmental noise outside the speaker.

8. The acoustic noise reduction system for closed space noise reduction according to claim 1, characterized in that: The auxiliary noise sensor is used to collect the vibration of the sound housing and the sound emitted by the speaker.

9. A sound system for noise reduction in a closed space, characterized in that: The audio noise reduction system applied to any one of claims 1-8, wherein the audio used for noise reduction processing in a closed space includes a hardware board for carrying the audio noise reduction system.

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