Speech masking and cancelling and voice obscuration

Abstract

A non-acoustic sensor is used to measure a user's speech and then broadcasts an obscuring acoustic signal diminishing the user's vocal acoustic output intensity and/or distorting the voice sounds making them unintelligible to persons nearby.

1 . An apparatus for measure a user's speech and broadcasting an obscuring acoustic signal diminishing the users vocal acoustic output intensity or distorting the voice sounds or both diminishing the users vocal acoustic output intensity and distorting the voice sounds making them unintelligible to persons nearby wherein the user has neck or head skin tissue, comprising:
 a non-acoustic sensor proximate or contacting the users neck or head skin tissue for sensing speech production information,   a processor using said speech production information for producing an obscuring acoustic signal, and   a device for broadcasting said obscuring acoustic signal diminishing the user's vocal acoustic output intensity or distorting the voice sounds or both diminishing the user's vocal acoustic output intensity and distorting the voice sounds making them unintelligible to persons nearby.   
     
     
         2 . The apparatus of claim I wherein said non-acoustic sensor is a low-power electromagnetic radar. 
     
     
         3 . The apparatus o claim I wherein said non-acoustic sensor is an electromagnetic interferom eter with antenna. 
     
     
         4 . The apparatus of  claim 1  wherein said non-acoustic sensor is an accelerometer in contact with the user's neck or head skin tissue. 
     
     
         5 . The apparatus of claim I wherein said non-acoustic sensor is a laser interferometer vibration sensor. 
     
     
         6 . The apparatus of claim I wherein said non-acoustic sensor is a partially coherent optical vibration sensor. 
     
     
         7 . The apparatus of  claim 1  wherein said non-acoustic sensor is a microphone in contact with the user's skin surface. 
     
     
         8 . The apparatus of  claim 1  wherein said non-acoustic sensor is an electric field sensor that detects muscle electrical signals associated with motions. 
     
     
         9 . A method of measuring both a user's speech and also measuring a user's speech production for voiced speech time periods, and then broadcasting an obscuring acoustic signal diminishing the user's vocal acoustic output intensity or distorting the voice sounds or both diminishing the uses's vocal acoustic output intensity and distorting the voice sounds making them unintelligible to persons or instruments nearby, comprising the steps of:
 using a non-acoustic sensor proximate to or contacting the user's neck or head for sensing speech production, using an acoustic sensor to measure and record user's emitted speech signals, then using said non-acoustic sensor signals and said recordings of user's prior acoustic speech signals, calculating an obscuring and/or canceling signal, then broadcasting said calculated signal as an acoustic signal diminishing the user's vocal acoustic output intensity or distorting the voice sounds or both diminishing the user's vocal acoustic output intensity and distorting the voice sounds making them unintelligible to persons or sound sensing instruments nearby.   
     
     
         10 . The method of  claim 9  for obtaining the moment in future time when obscuring and canceling acoustic emissions are broadcast, whereas said future time is estimated by adding a prior determined delay-time-value to the time in the present voiced-speech period when a non-acoustic sensor measures the fastest negative-going signal of vocal fold closure, and whereas said prior determined delay-time-value was obtained from data recorded during a prior speech time period, during which the start time in said prior time period was defined as the time of the negative vocal fold closure signal and the end time in said prior time period was defined as the corresponding time of the negative acoustic signal, the difference between the prior start time and the prior end time gives said prior determined delay-time-value. 
     
     
         11 . The method of  claim 9  for identifying and then canceling and obscuring an unvoiced speech segment by using non-acoustic and acoustic sensors to identify the onset of said unvoiced speech period in a time period short compared to its duration, then using a processor to select the appropriate signal to transmit to a loudspeaker, including the choice of transmitting a pink noise, selected noise, or determinate noise signal, and then broadcasting said selected noise-like signal for the rest of the unvoiced speech time period and into the following time period of voiced or silent speech as needed for best obscuration. 
     
     
         12 . The method of  claim 9  for identifying and then canceling and obscuring a silent speech segment by using non-acoustic and acoustic sensors to identify the onset of said silent speech period rapidly compared to its duration, then using a processor to select the appropriate signal to transmit to a loudspeaker, including the choice of transmitting a zero amplitude signal or a prior recorded noise background signal, then broadcasting a selected noise-like or silent signal for the rest of the silent speech time period. 
     
     
         13 . The method of  claim 9  and  claim 10  including an algorithm that modifies the non-acoustic sensor signal by altering its amplitude, its phase, its amplitude vs frequency, its phase versus frequency, its delay, its polarity, and its format for broadcast at a determined time in the future by a loud speaker which causes a reduction in intensity and intelligibility as detected by a listener. 
     
     
         14 . The method of  claim 9  and  claim 10  including an algorithm that modifies an acoustic sensor signal by altering its amplitude, its phase, its amplitude vs frequency, its phase versus frequency, its delay, its polarity, and its format for broadcast at a determined time in the future by a loud speaker which causes a reduced intensity and intelligibility, as detected by a listener. 
     
     
         15 . The method of  claim 11  and  claim 12  such that the resulting signal as broadcast in the future by a loudspeaker both reduces the intensity and reduces the intelligibility for at least 3 kinds of human speech so that the speakers voice is reduced in intensity and obscured as detected by a listener or sound detecting instrument. 
     
     
         16 . The method of  claim 10 ,  11 ,  12 ,  13 , and  14  in which a non-acoustic sensor and algorithms, in conjunction with prior acoustic signals from an acoustic speech sensor, are used to generate an obscuring signal, while an all-acoustic noise-canceling microphone and prior art noise reducing algorithms enable the user to detect his/her own undistorted or undiminished speech signal for subsequent use. 
     
     
         17 . The method of  claim 16  in which the output signal from a noise-canceling microphone and from noise reducing algorithms provide a signal sufficiently free of background noise, obscuring noise, canceling noise, and other system noise that said signal when conveyed to the user's own ear or ears and to other instruments, has a low noise level and is highly intelligible as defined by the user.