Abstract:
A method of controlling the volume level of an audio signal in a vehicle includes the computer-implemented steps of detecting human speech within a passenger compartment of the vehicle, and automatically adjusting, dependent upon the detecting step, a volume level within the passenger compartment of an audible signal being presented by an audio system of the vehicle.

Description:
CROSS-REFERENCED TO RELATED APPLICATIONS 
       [0001]    This application claims benefit of U.S. Provisional Application No. 62/195,891 filed on Jul. 23, 2015, which the disclosure of which is hereby incorporated by reference in its entirety for all purposes. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The disclosure relates to a method of controlling an audio signal in a vehicle, and, more particularly, to a method of controlling the volume of an audio signal in a vehicle. 
       BACKGROUND OF THE INVENTION 
       [0003]    It is normal that during a long trip passengers listen to loud music but will like to have intermittent conversation among the other passengers. Currently, in order for the passengers to hear each other, a passenger must manually turn down the volume in response to the start of a conversation, and manually turn the volume back up in response to the end of the conversation. More particularly, when a rear seat passenger talks while audio is being played at a high volume, the driver and passenger in the front seat may not hear the rear seat passenger clearly. The driver or front seat passenger may need to reduce the volume manually or the rear seat passenger may need to shout in order to be heard by the other passengers. 
       SUMMARY 
       [0004]    The present invention may reduce the car audio volume automatically when the passengers and driver inside the car start speaking with each other. The system may monitor for speech and reduce the audio volume level when speech is detected. When the passenger conversation is no longer detected, the audio volume may be automatically increased back to its former pre-conversation volume level. The system may periodically monitor for speech in order to be able to reduce the volume and set the volume back to its former increased level. 
         [0005]    A user is able to turn off this automatic volume change feature if he prefers. For example, a user may want to turn off the feature if the passengers are singing along with the song or if the user does not want to listen to what the other passenger is saying. 
         [0006]    Currently, such an automatic volume control to help ease passenger communication is not present in any commercial car audio system. Thus, the present invention provides a unique convenience feature for the car users. The car passengers may have to speak louder or reduce audio volume manually with the existing systems. With the inventive system, in contrast, the volume level may be automatically controlled based on detection of the passenger&#39;s speech. 
         [0007]    In one embodiment, the invention comprises a method of controlling the volume level of an audio signal in a vehicle, including the computer-implemented steps of detecting human speech within a passenger compartment of the vehicle, and automatically adjusting, dependent upon the detecting step, a volume level within the passenger compartment of an audible signal being presented by an audio system of the vehicle. 
         [0008]    In another embodiment, the invention comprises a method of controlling an audio signal in a vehicle, including the following computer-implemented steps. An audio signal is played at a first volume level within a passenger compartment of the vehicle. In response to detecting human speech within the passenger compartment of the vehicle, the volume of the audio signal as played within the passenger compartment is reduced to a second volume level that is lower than the first volume level. In response to ascertaining that the human speech within the passenger compartment of the vehicle has ceased, the volume of the audio signal as played within the passenger compartment is increased to a third volume level that is higher than the second volume level. 
         [0009]    In yet another embodiment, the invention comprises a motor vehicle including an infotainment arrangement having a loudspeaker emitting first audible sounds within a passenger compartment of the vehicle based on an audio signal received by the loudspeaker. A microphone produces a microphone signal dependent upon the first audible sounds and upon human speech detected within the passenger compartment of the vehicle. A noise cancellation module receives the audio signal and the microphone signal, and removes effects of the audio signal from the microphone signal to thereby transmit a speech signal. A processor receives the speech signal from the noise cancellation module, determines whether the speech signal indicates a presence of human speech, and reduces a volume of the audio signal if the speech signal indicates a presence of human speech. 
         [0010]    Automatically reducing the volume of the audio head unit based on recognition of the human conversation helps the inmates of the car communicate clearly without needing to manually reduce the audio volume or talk louder. 
         [0011]    The invention may solve the following problems:
       1. Passengers in the car not being able to have a clear conversation because of high audio unit volume level.   2. Passengers having to manually reduce the volume level in order for speech to be heard among the passengers.   3. Passengers having to speak louder in order for their voices to be heard by the other passengers amidst the high audio volume.       
 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    A better understanding of the present invention will be had upon reference to the following description in conjunction with the accompanying drawings. 
           [0016]      FIG. 1  is a block diagram of one embodiment of an automatic vehicle audio volume control system of the present invention. 
           [0017]      FIG. 2  is a block diagram of another embodiment of an automatic vehicle audio volume control system of the present invention. 
           [0018]      FIG. 3  is a flow chart of one example embodiment of an automatic passenger conversation volume control method of the present invention. 
           [0019]      FIG. 4  is a flow chart of another example embodiment of an automatic passenger conversation volume control method of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0020]      FIG. 1  illustrates one embodiment of an automatic vehicle audio volume control system  10  of the present invention, including a processor  12 , a noise cancelled microphone  14 , and a loudspeaker  16 . During use, processor  12  sends audio signals  18  to loudspeaker  16  to drive speaker  16  and cause sound (e.g., music) to be produced by speaker  16 . Microphone  14  may be disposed in the passenger compartment of a vehicle  20  in which system  10  is installed. Microphone  14  detects sound within the passenger compartment and sends a microphone signal  22  based on the detected sounds to processor  12 . Processor  12  determines whether signal  22  includes any speech sound that did not originate from speaker  16  and audio signal  18 . If so, it is determined that the speech sound originates from a human conversation in the passenger compartment. The conversation may include multiple passengers, or only a single passenger who is talking to the other passengers or talking on a mobile phone. In response to detecting the human conversation, processor  12  may reduce the audio volume of signal  18 . When processor  12  determines from subsequent signals  22  that the conversation has ceased, such as after a threshold period of time without human speech, processor  12  may return audio signal  18  to its initial volume level that was in effect before the conversation. 
         [0021]    In the more specific embodiment of  FIG. 2 , a noise cancellation block is shown to cancel audio signal  118  from microphone signal  122 . Thus, a noise cancelled signal  124  received by processor  112  may represent only the speech detected by microphone  114 . 
         [0022]      FIG. 3  illustrates an embodiment of a method  300  of the present invention for automatically controlling the volume of a vehicle audio system. In a first step  302 , microphone input is obtained. For example, microphone  114  may produce a signal  122  based on sound detected in a vehicle passenger compartment. 
         [0023]    Next, in step  304 , noise in the input is reduced. That is, noise cancellation module  126  may remove the effects of audio signal  118  from microphone signal  122  to thereby produce noise cancelled speech signal  124 . 
         [0024]    In a next step  306 , it is determined whether the signal is speech input. That is, processor  112  may determine whether signal  124  indicates the presence of any human speech. Processor  112  may analyze the frequencies of signal  124  to make this determination. For example, road noise or engine noise may have different frequencies than human speech. If it is determined that signal  124  does not include speech, then operation proceeds to step  308  where there is one second of waiting time. Operation then goes back to step  302 . On the other hand, if it is determined in step  306  that signal  124  does indeed include speech, then operation proceeds to step  310  where the volume level of the car audio system is reduced so that the speech by the passenger may be more easily heard. Next, one second of waiting occurs in step  312 , and operation proceeds back to step  302  where the above-described process is cyclically repeated. 
         [0025]      FIG. 4  illustrates another embodiment of a method  400  of the present invention for automatically controlling the volume of a vehicle audio system. In a first step  402 , an audio signal is played at a first volume level within a passenger compartment of the vehicle. In a second step  404 , human speech is detected within the passenger compartment of the vehicle. For example, microphone signals  22  from microphone  14  may be received by processor  12 , and processor  12  may determine that signals  22  are the result of speech based on the frequencies that are present in signals  22 . Next, in step  406 , in response to the detecting of the speech, the volume of the audio signal as played within the passenger compartment is automatically reduced to a second volume level that is lower than the first volume level. That is, processor  12  may reduce the audio volume of signal  18 . In step  408 , it is ascertained that the human speech within the passenger compartment of the vehicle has ceased. For example, processor  12  may determine that signals  22  no longer include the frequencies that are characteristic of human speech. In a final step  410 , in response to sensing that the speech has stopped, the volume of the audio signal as played within the passenger compartment is increased to a third volume level that is higher than the second volume level. That is, processor  12  may increase the audio volume of signal  18  such that it is played louder than it was while the speech was occurring. The present invention has been described as adjusting audio volume in response to the detection or non-detection of sounds originating from audible speech. However, in other embodiments, the presence of human speech is detected in other ways. In one embodiment, lip movement of the driver and passenger is detected by using a camera, and such lip movement is considered an indication of the presence of speech. 
         [0026]    In another embodiment, a command spoken by a user, or the press of a button by a user, is detected and considered an indication of the presence of speech, and thus may trigger a reduction in the audio volume. Although this embodiment may not provide a fully automatic method of reducing and then restoring the volume of the audio system, this embodiment may provide a smart and convenient feature to facilitate clear conversation between the passengers of the car. 
         [0027]    The foregoing description may refer to “motor vehicle”, “automobile”, “automotive”, or similar expressions. It is to be understood that these terms are not intended to limit the invention to any particular type of transportation vehicle. Rather, the invention may be applied to any type of transportation vehicle whether traveling by air, water, or ground, such as airplanes, boats, etc. 
         [0028]    The foregoing detailed description is given primarily for clearness of understanding and no unnecessary limitations are to be understood therefrom for modifications can be made by those skilled in the art upon reading this disclosure and may be made without departing from the spirit of the invention.