SYSTEMS AND METHODS FOR DETECTING A GUNSHOT
Systems and methods for detecting a gunshot event are disclosed. More particularly, systems and methods for detecting a gunshot event using the ultrasonic frequency distribution across a broad range of frequencies resulting from a gun's muzzle blast to determine whether an actual gunshot event has occurred and to minimize false positives and false negatives are disclosed. Yet further, systems and methods for determining the location of an actual gunshot event by utilizing the decay of the frequency distribution across a broad range of frequencies resulting from a gun's muzzle blast are disclosed.
1 . A method for determining the occurrence of a gunshot comprising:
a) capturing a digital audio signal with such fidelity that the constituent frequencies that comprise ultrasonic frequencies are retained and preserved;
b) mathematically transforming the captured data by creating a spectrogram having a spectrum of frequencies of the signal as it varies with time; and
c) determining whether the spectrogram or sampled portions thereof contains a short-duration, high-energy, wide-spectrum, ultrasonic burst that corresponds to an ultrasonic signature of a gunshot.
2 . A method for determining the occurrence of a gunshot comprising:
a) capturing a digital audio signal with such fidelity that the constituent frequencies that comprise the ultrasonic frequencies are retained and preserved;
b) mathematically transforming the captured data by creating a spectrum of frequencies over a short period of time; and
c) determining whether the spectrum or sampled portions thereof contains a short-duration, high-energy, wide-spectrum, ultrasonic burst that corresponds to an ultrasonic signature of a gunshot.
3 . A method for accurately determining the occurrence of a gunshot comprising:
a) capturing an audio signal, either digital or analog, with such fidelity that the constituent frequencies that comprise the ultrasonic frequencies are retained and preserved;
b) utilizing at least one bandpass filter to capture one or more discrete samples within the ultrasonic spectrum of frequencies; and
c) determining whether said one or more discrete samples are consistent with a short-duration, high-energy, wide-spectrum, ultrasonic burst that corresponds to an ultrasonic signature of a gunshot.
4 . The method of claim 1 , wherein the step of capturing an audio signal includes sampling the audio source at a sampling rate that is at least twice the highest discrete ultrasonic frequency sought to be captured.
5 . The method of claim 1 wherein the step of mathematically transforming utilizes calculating a Fast Fourier Transformation in accordance with any known FFT algorithm.
6 . The method of claim 1 wherein the step of mathematically transforming utilizes calculating a Fast Fourier Transformation in accordance with known FFT implementation.
7 . The method of claim 1 further comprising detecting an impulse prior to executing the mathematical transformation step that yields the spectrogram.
8 . The method of claim 2 wherein the step of capturing the audio signal includes sampling the audio source for frequency information in the supersonic range above 30 kHz.
9 . The method of claim 3 further comprising detecting an impulse prior to filtering.
10 . The method of claim 1 further comprising transmitting the captured digital audio signal to a second location for storage or further processing.
11 . The method of claim 1 further comprising transmitting said spectrogram to a second location for storage or further processing.
12 . The method of claim 2 further comprising transmitting said spectrum to a second location for storage or further processing.
13 . The method of claim 1 further comprising transmitting the captured digital audio signal to a second location prior to executing the mathematical transformation step that yields the spectrogram.
14 . The method of claim 3 further comprising transmitting the captured digital audio signal to a second location prior to filtering.
15 . The method of claim 1 wherein the step of determining a gunshot utilizes a correlation function to determine whether the spectrogram corresponds to a known ultrasonic signature of a gunshot.
16 . The method of claim 1 wherein the step of determining a gunshot utilizes Artificial Intelligence to determine whether the spectrogram corresponds to a known ultrasonic signature of a gunshot.
17 . The method of claim 2 wherein the step of determining a gunshot utilizes a correlation function to determine whether the spectrum corresponds to a known ultrasonic signature of a gunshot.
18 . The method of claim 2 wherein the step of determining a gunshot utilizes Artificial Intelligence to determine whether the spectrum corresponds to a known ultrasonic signature of a gunshot.
19 . The method of claim 3 wherein the step of determining a Gunshot utilizes a correlation function to determine whether the discrete samples correspond to a known ultrasonic signature of a Gunshot.
20 . The method of claim 3 wherein the step of determining a Gunshot utilizes Artificial Intelligence to determine whether the discrete samples correspond to a known ultrasonic signature of a Gunshot.
21 . A detection device for determining the occurrence of a Gunshot comprising:
a) a microphone that is capable of capturing acoustic frequencies within the ultrasonic spectrum, above 30 kHz, for capturing an audio signal;
b) an analog to digital converter for converting the microphone's analog audio signal to a digital audio signal;
c) a processing circuit for processing and analyzing the resulting digital audio signal; and
d) a data storage device for retaining and preserving any captured or analyzed data wherein:
said microphone and analog to digital converter capture a digital audio signal with such fidelity that the constituent frequencies that comprise the ultrasonic spectrum are retained and preserved;
said processing circuit mathematically transforms the captured data by creating a spectrogram having a spectrum of frequencies of the signal as it varies with time;
said processing circuit determines whether said spectrogram or sampled portions thereof contain a short-duration, high-energy, wide-spectrum, ultrasonic burst, that corresponds a known ultrasonic signature of a Gunshot; and
said storage device retains and preserves the data as it is captured, transformed and used for determination.
22 . A detection device for determining the occurrence of a Gunshot comprising:
a) a microphone capable of capturing acoustic frequencies within the ultrasonic spectrum, from about 20 kHz to about 200 kHz, for capturing an audio signal;
b) an analog to digital converter for converting the microphone's analog audio signal to a digital audio signal;
c) a processing circuit for processing and analyzing the resulting digital audio signal; and
d) a data storage device for retaining and preserving any captured or analyzed data wherein:
said microphone and analog to digital converter capture a digital audio signal with such fidelity that the constituent frequencies that comprise the ultrasonic spectrum are retained and preserved;
said processing circuit mathematically transforms the captured data by creating a spectrum of frequencies over a short period of time;
said processing circuit determines whether said spectrum or sampled portions thereof contain a short-duration, high-energy, wide-spectrum, ultrasonic burst, that corresponds to a known ultrasonic signature of a Gunshot; and
said storage device retains and preserves the data as it is captured, transformed and used for determination.
23 . A detection device for determining the occurrence of a Gunshot comprising:
a) a microphone capable of capturing acoustic frequencies within the ultrasonic spectrum, above 20 kHz, for capturing an audio signal;
b) an analog to digital converter for converting the microphone's analog audio signal to a digital audio signal;
c) a processing circuit for processing and analyzing the resulting digital audio signal;
d) a data storage device for retaining and preserving any captured or analyzed data wherein:
The microphone and analog to digital converter capture a digital audio signal with such fidelity that the constituent frequencies that comprise the ultrasonic spectrum are retained and preserved;
The processing circuit mathematically applies a bandpass filter(s) to capture discrete sample(s) within the ultrasonic spectrum of frequencies;
The processing circuit determines whether the discrete sample(s) are consistent with the characteristic short-duration, high-energy, wide-spectrum, ultrasonic burst, that corresponds to the known ultrasonic signature of a gunshot; and
said storage device is for retaining and preserving the data as it is captured, transformed and used for determination.
24 . A detection device for determining the occurrence of a gunshot comprising:
a) a microphone capable of capturing acoustic frequencies within the ultrasonic spectrum, above 30 kHz, for capturing an audio signal;
b) at least one filtering circuit;
c) a processing circuit for processing and analyzing the resulting digital audio signal, wherein:
said microphone provides an analog output with such fidelity that the constituent frequencies that comprise the ultrasonic spectrum are retained and preserved within its output;
said at least one filtering circuit applies at least one bandpass filter to limit at least one discrete sample within said ultrasonic spectrum of frequencies;
said processing circuit determines whether said at least one discrete sample obtained is consistent with a short-duration, high-energy, wide-spectrum, ultrasonic burst, that corresponds to a known ultrasonic signature of a gunshot.
25 . The detection device of claim 24 further comprising a sensor for detecting an impulse prior to filtering.
26 . The detection device of claim 21 wherein, responsive to a gunshot determination, the processing circuit records at least one of a date and time of occurrence of the determination.
27 . The detection device of claim 22 wherein said device includes a GPS receiver for acquiring the geographic location of the system.
28 . The detection device of claim 23 wherein said device includes a transmitter for conveying data and a receiver for receiving data.
29 . The detection device of claim 24 wherein said device includes a display screen.
30 . The detection device of claim 21 wherein said device includes a mounting system wherein:
a) said mounting system integrates with a standard wall outlet; and
b) said mounting system utilizes the wall outlet receptacle as a source of power and alignment.
31 . The detection device of claim 30 further comprising a mounting system that utilizes a security fastener to prevent unwarranted removal.
32 . The detection device of claim 21 wherein said device includes means for electronically publishing a report.