Patent Publication Number: US-2020296534-A1

Title: Sound playback device and output sound adjusting method thereof

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a sound playback device and an output sound adjusting method thereof particularly to a sound playback device and an output sound adjusting method thereof that can be adjusted according to the frequency range of external noise. 
     2. Description of the Related Art 
     Nowadays, it is common for users to listen to sounds using devices such as stereos, Walkman or smart phones. But when listening to the sound signal, it may also be disturbed by external noise. in the prior art, it is usually necessary to shield all external noise. However, this method is costly. if it is used for the speaker to listen to the sound, it cannot achieve the effect of shielding the external noise. Another method is to increase the volume of the sound signal to cover the external noise when there is external noise. However, this method cannot make proper adjustments to the frequency range of external noise, and eventually the effect of the user&#39;s listening is not fine enough. 
     Accordingly, it is necessary to devise a new sound playback device and an output sound adjusting method thereof to solve the problem in the prior art. 
     SUMMARY OF THE INVENTION 
     It is a major objective of the present invention to provide a sound playback system that can be adjusted according to the frequency range of external noise. 
     It is another objective of the present invention to provide an output sound adjusting method used for the aforementioned sound playback system. 
     To achieve the above objectives, the sound playback device of the present invention includes a sound receiving module, a noise detector, a noise analysis module, a sound processing module, and a speaker module. The sound receiving module is used to obtain an input sound signal and know an average input volume of the input sound signal. The noise detector is used to detect an ambient noise. The noise analysis module is electrically connected to the noise detector for analyzing an average noise volume and a noise frequency band of the ambient noise. The sound processing module is electrically connected to the sound receiving module and the noise analysis module to determine whether he average noise volume of the ambient noise is louder than the average input volume. If yes, the sound processing module adjusts a specific frequency band of the input sound signal to increase a first gain value to form an output sound signal, wherein the specific frequency band and the noise frequency band of the ambient noise belongs to the same frequency band or different frequency hand, The speaker module is electrically connected to the sound processing module for playing the output sound signal. 
     An output sound adjusting method of the present invention includes the following steps: obtaining an input sound signal and knowing an average input volume of the input sound signal; detecting an ambient noise, and analyzing an average noise volume and a noise frequency band of the ambient noise; determining whether the average noise volume of the ambient noise is louder than the average input volume; if yes, adjusting a specific frequency band of the input sound signal to increase a first gain value to form an output sound signal, wherein the specific frequency band and the noise frequency band of the ambient noise belongs to the same frequency band or different frequency band; and playing the output sound signal. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an architecture diagram of a sound playback device in the present invention; 
         FIG. 2  is a flowchart showing steps of an output sound adjusting method in the present invention; 
         FIG. 3  is a waveform diagram of adjusting output sound in a first embodiment of the present invention; 
         FIG. 4  is a waveform diagram of adjusting output sound in a second embodiment of the present invention; 
         FIG. 5  is a waveform diagram of adjusting output sound in a third embodiment of the present invention; 
         FIG. 6  is a waveform diagram of adjusting output sound in a fourth embodiment of the present invention; 
         FIG. 7  is a waveform diagram of adjusting output sound in a fifth embodiment of the present invention; and 
         FIG. 8  is a waveform diagram of adjusting output sound in a sixth embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Hereafter, the technical content of the present invention will be better understood with reference to preferred embodiments. 
     Hereafter, please refer to  FIG. 1 , which is an architecture diagram of a sound playback device in the present invention. 
     A sound playback device  10  of the present invention includes a sound receiving module  20 , a noise detector  30 , a sound processing module  50 , and a speaker module  60 . The sound receiving module  20  is used to obtain an input sound signal, and know an average input volume of the input sound signal. In different embodiments of the present invention, the sound receiving module  20  may be a microphone or other signal receiving device to receive sound signals generated by the external or other devices. However, the present invention does not limit the sound receiving mode or receiving path of the sound receiving module  20 . 
     The noise detector  30  can be a microphone, which is electrically connected to the sound receiving module  20  for detecting ambient noise outside the sound playback device  10 . The noise analysis module  40  is electrically connected to the noise detector  30  for analyzing the average noise volume of the ambient noise obtained by the noise detector  30  and knowing a noise frequency band of the ambient noise. For example, as shown in  FIG. 3 , the noise detector  30  can know that the ambient noise belongs to a frequency band of 32 Hz, 64 Hz, 125 Hz, 250 Hz, 500 Hz, 1000 Hz, 2000 Hz, 4000 Hz, 8000 Hz or 16000 Hz, or the ambient noise can also be distributed to more than one frequency band simultaneously. The above-mentioned frequency bands are only illustrative, and the present invention is not limited thereto. The noise analysis module  40  can determine whether the average noise volume of the ambient noise is louder than the average input volume. If yes, the noise analysis module  40  can further determine whether the volume difference of the average noise volume and the average input volume exceeds a threshold. For example, when the average input volume of the input sound signal is 60 dB, if the average noise volume of the ambient noise exceeds the average input volume by 20 dB, it is determined that the average noise volume of the ambient noise exceeds the threshold. However, the present invention does not limit the set threshold value. 
     The sound processing module  50  is electrically connected to the sound receiving module  20  and the noise analysis module  40 . The sound processing module  50  can be an equalizer (EQ) used to adjust the gain value of the sound signal band. The equalizer is a tool that can be used with adjustable sound output to change a gain value of sounds in different frequency bands, so it is often used to adjust the output sound. When the noise analysis module  40  determines that the average noise volume of the ambient noise is louder than the average input volume, the sound processing module  50  can adjust the volume of the specific sound band according to the volume characteristic of the ambient noise to increase a first gain value to form an output sound signal. Here, the specific frequency band and the noise frequency band of the ambient noise belong to the same frequency band or different frequency bands. The sound processing module  50  can also adjust other input sound signals that do not belong to the specific frequency band. When the volume difference of the average noise volume and the average input volume exceeds a threshold, the sound processing module  50  can increase a second gain value for other input sound signals that do not belong to the specific frequency band. When the volume difference of the average noise volume and the average input volume is less than the threshold, the sound processing module  50  can decrease the second gain value for other input sound signals that do not belong to the specific frequency band. Specifically, the second gain value is less than the first gain value. That is, the sound processing module  50  does not perform the same volume adjustment for all the bands of the input sound signal. The sound processing module  50  can only adjust the frequency band of the input sound signal that is the same as the noise frequency band, or only adjust the frequency band of the input sound signal that is different from the noise frequency band. Furthermore, the sound processing module  50  can adjust all the frequency bands of the input sound signal, but the adjustment of the specific frequency band is different from that of the non-specific frequency band. The degree of adjustment is changed according to the noise frequency band of the ambient noise, and the present invention is not limited to only adjusting the two gain values. The sound processing module  50  can also adjust three or more gain values simultaneously, 
     Finally, the speaker module  60  is electrically connected to the sound processing module  50  for playing the output sound signal, The speaker module  60  can be a headset or a speaker, but the present invention is not limited thereto. in this way, the output sound signal played by the speaker module  60  can reduce the interference of external noise when the user uses it. 
     it should be noted that each module of the sound playback device  10  may be configured as a hardware device, software program with hardware device, or firmware with hardware device, e.g. a computer program product stored in a computer readable medium and read and executed to achieve the functions of the present invention. However, the present invention is not limited to the above-described manner. Additionally, the preferred embodiments of the present invention described above are only illustrative. To avoid redundancy, all the possible combinations of changes are not documented in detail. However, it shall be understood by those skilled in the art that each of the modules or elements described above may not be necessary. For the implementation of the present invention, the present invention may also contain other detailed, conventional modules or elements. Each module or component is likely to be omitted or modified depending on the needs. Other modules or elements may at necessarily exist between two of any modules. 
     Then, please refer to  FIG. 2 , which is a flowchart showing steps in an output sound adjusting method of the present invention. It should be noted here that although the aforementioned sound playback device  10  is taken as an example to illustrate an output sound adjusting method of the present invention, the output sound adjusting method in the present invention is not limited to the sound playback device  10  using the same structure as described above. 
     First, the sound playback device  10  performs Step  201 : Obtaining an input sound signal and knowing an average input volume of the input sound signal. 
     The sound receiving module  20  first obtains an input sound signal, such as the sound signal generated by the external or other device, but the present invention is not limited thereto. Also, the sound receiving module  20  can also know an average input volume of the input sound signal. 
     Then, in Step  202 : Detecting an ambient noise, and analyzing an average noise volume and a noise frequency band of the ambient noise. 
     The noise detector  30  detects the ambient noise outside the is sound playback device  10 , analyzes the average noise volume of the ambient noise obtained by the noise detector  30  by using the noise analysis module  40 , and knows a noise frequency band of the ambient noise. The noise analysis module  40  can find out which frequency band the noise frequency band belongs to, such as 32 Hz, 64 Hz, 125 Hz, 250 Hz, 500 Hz, 1000 Hz, 2000 Hz; 4000 Hz, 8000 Hz or 16000 Hz, but the present invention is not limited thereto. 
     Next, the sound processing module  50  performs Step  203 : Determining whether the average noise volume of the ambient noise is louder than the average input volume. 
     The noise analysis module  40  then determines whether the average noise volume of the ambient noise is louder than the average input volume 
     When the average noise volume of the ambient noise is louder than the average input volume, the sound processing module  50  can perform Step  204 : Adjusting a specific frequency band of the input sound signal to increase a first gain value. 
     The sound processing module  50  can adjust a specific frequency band of the input sound signal to increase a first gain value to form an output sound signal. Here, the specific frequency band and the noise frequency band of the ambient noise belong to the same frequency band or different frequency bands. Accordingly, hereafter please refer to  FIG. 3 , which is a waveform diagram of adjusting output sound in a first embodiment of the present invention. 
     In the first embodiment of the present invention, the specific frequency band and the noise frequency band of the ambient noise belongs to the same frequency band. Therefore, after the noise analysis module  40  confirms that the noise frequency band is 500 Hz, the sound processing module  50  increases the first gain value  71  to the original gain value  70  of the input sound signal belonging to the 500 Hz band. The first gain value  71  can be 15 dB or greater than 15 dB, but the present invention is not limited thereto. Therefore, the output sound signal of the 500 Hz band is equivalent to the original gain value  70  plus the first gain value  71 . 
     In addition, after Step  203 , Step  205  can also be simultaneously performed: Determining whether the volume difference of the average noise volume and the average input volume of the ambient noise exceeds a threshold. 
     The noise analysis module  40  can further determine whether the volume difference of the average noise volume and the average input volume exceeds a threshold, 
     If the volume difference of the average noise volume and the average input volume exceeds a threshold, Step  206  will be performed: Increasing a second gain value for frequency bands other than the specific frequency band. 
     When the volume difference of the average noise volume and the average input volume exceeds a threshold, the sound processing module  50  can increase a second gain value for other input sound signals that do not belong to the specific frequency band. Hereafter, please refer to  FIG. 4 , which is a waveform diagram of adjusting output sound in a second embodiment of the present invention. 
     In the second embodiment of the present invention, the sound processing module  50  not only increases the first gain value  71  to the original gain value  70  of the input sound signal belonging to the 500 Hz band, but increases the second gain value  72   a  to the original gain value  70  of the input sound signal belonging to other frequency bands. Specifically, the second gain value  72   a  is less than the first gain value  71 , e.g. 0-5 dB, but the present invention is not limited thereto. Therefore, the output sound signal outside the 500 Hz band is equivalent to the original gain value  70  plus the second gain value  72   a.    
     If the volume difference of the average noise volume and the average input volume is less than a threshold, Step  207  will be performed: Decreasing a second gain value for frequency bands other than the specific frequency band. 
     When the volume difference of the average noise volume and the average input volume is less than the threshold, the sound processing module  50  can decrease a second gain value  72   b  for other input sound signals that do not belong to the specific frequency band. Then, please refer to  FIG. 5 , which is a waveform diagram of adjusting output sound in a third embodiment of the present invention. 
     In the third embodiment of the present invention, the sound processing module  50  not only increases the first gain value  71  to the original gain value  70  of the input sound signal belonging to the 500 Hz band, but decreases the second gain value  72   b  from the original gain. value  70  of the input sound signal belonging to other frequency bands. Similarly, the second gain value  72   b  is less than the first gain value  71 , e.g. 0-5 dB, but the present invention is not limited thereto, Therefore, the output sound signal outside the  500   1 -lz hand is equivalent to the original gain value  70  minus the second gain value  72   b.    
     Then, please refer to  FIG. 6 , which is a waveform diagram of adjusting output sound in a fourth embodiment of the present invention. 
     In the fourth embodiment of the present invention, the specific frequency band and the noise frequency band of the ambient noise belong to different frequency bands. Therefore, after the noise analysis module  40  confirms that the noise frequency band is 500 Hz, the sound processing module  50  increases the first gain value  71 ′ to the original gain value  70  of the input sound signal that does not belong to the 500 Hz band. The first gain value  71 ′ can also be 15 dB or greater than 15 dB, but the present invention is not limited thereto. Therefore, the output sound. signal outside the 500 Hz band is equivalent to the original gain value  70  plus the first gain value  71 ′. 
     Then, please refer to  FIG. 7 , which is a waveform diagram of adjusting output sound in a fifth embodiment of the present invention. 
     The fifth embodiment of the present invention is equivalent to the case in Step  206  where the volume difference of the average noise volume and the average input volume exceeds the threshold. The sound processing module  50  not only increases the first gain value  71 ′ to the original gain value  70  of the input sound signal that does not belong to the 500 Hz band, but increases the second gain value  72   c  to the original gain value  70  of the input sound signal belonging to the 500 Hz band. Similarly, the second gain value  72   c  is less than the first gain value  71 ′, e,g. 0-5 dB, but the present invention is not limited thereto. Therefore, the output sound signal of the 500 Hz band is equivalent to the original gain value  70  plus the second gain value  72   c.    
     Finally, please refer to  FIG. 8 , which is a waveform diagram of adjusting output sound in a sixth embodiment of the present invention. 
     The sixth embodiment of the present invention is equivalent to the case in Step  207  where the volume difference of the average noise volume and the average input volume is less than the threshold. The sound processing module  50  not only increases the first gain value  71 ′ to the original gain value  70  of the input sound signal that does not belong to the 500 Hz band, but decreases the second gain value  72   d  from the original gain value  70  of the input sound signal belonging to the 500 Hz band, Similarly, the second gain value  72   d  is less than the first gain value  71 ′, e.g. 0-5 dB, but the present invention is not limited thereto. Therefore, the output sound signal of the 500 Hz band is equivalent to the original gain value  70  minus the second gain value  72   d.    
     Finally, in Step  208 : Forming and playing an output sound signal. 
     After the processing of Step  204 , Step  206  or Step  207 , the sound processing module  50  can form an output sound signal. Therefore, the output sound signal can be adjusted by the first to sixth embodiments. In the first embodiment, the first gain value  71  is increased for the input sound signal that has the same frequency band with the noise frequency band; in the second embodiment, the first gain value  71  is increased for the input sound signal that has the same frequency band with the noise frequency band, and the second gain value  72   a  is increased for the input sound signal that has a different frequency band with the noise frequency band; in the third embodiment, the first gain value  71  is increased for the input sound signal that has the same frequency band with the noise frequency band, and the second gain value  72   b  is decreased for the input sound signal that has a different frequency band with the noise frequency band; in the fourth embodiment, the first gain value  71 ′ is increased for the input sound signal that has a different frequency band with the noise frequency band; in the fifth embodiment, the first gain value  71 ′ is is increased for the input sound signal that has a different frequency band with the noise frequency band, and the second gain value  72   c  is increased for the input sound signal that has the same frequency band with the noise frequency band; in the sixth embodiment, the first gain value  71 ′ is increased for the input sound signal that has a different frequency band with the noise frequency band, and the second gain value  72   d  is decreased for the input sound signal that has the same frequency band with the noise frequency band. Finally, the speaker module  60  plays the output sound signal. In this way, through the above adjustment method in the first to the sixth embodiment, the output sound signal played by the speaker module  60  can reduce the noise interference to the user. 
     It should he noted here that the output sound adjusting method of the present invention is not limited to the order of the above steps, and the order of the above steps can be changed as long as the objectives of the present invention are achieved. 
     From the above description, according to the aforementioned embodiment, the user can reduce the interference of ambient noise when using the sound playback device  10 . 
     It should be noted that the embodiments of the present invention described above are only illustrative. All without departing from the scope of the invention are defined solely by the appended claims.