Agency:  National Institute of Justice

Award number:  2014-DN-BX-K034

Project Title:  Advancing audio forensics of gunshot acoustics

PI: Robert C. Maher

Summary

The primary applied research goal is to create an apparatus and methodology for scientific and repeatable collection of firearm acoustical properties recorded anechoically (without early sound reflections).  The primary development goal is to evaluate the extent to which useful forensic acoustical information can be obtained from recordings made by personal audio recorders of the type typically used by law enforcement officers.

The raw recording examples (.mat files) are available here.

 

FIGURE 1:  Recordings of a .308 rifle shot as a function of azimuth (0° azimuth is on-axis in front of the barrel, 180° is behind the shooting position).

.308 rifle shots

FIGURE 2: Recordings of a Glock 19 pistol shot as a function of azimuth (0° azimuth is on-axis in front of the barrel, 180° is behind the shooting position).

Glock 19 pistol shot

 

FIGURE 3: Recordings of a Ruger SP101 .357 caliber revolver shot as a function of azimuth (0° azimuth is on-axis in front of the barrel, 180° is behind the shooting position).

Ruger SP101 revolver shot

 FIGURE 4: Recordings of a 12 gauge shotgun shot as a function of azimuth (0° azimuth is on-axis in front of the barrel, 180° is behind the shooting position).

12 ga shotgun shot

FIGURE 5:  Recordings of an AR15 rifle shot as a function of azimuth (0° azimuth is on-axis in front of the barrel, 180° is behind the shooting position).

AR15 rifle shot

 

FIGURE 6: Recordings of a Colt M1911 0.45 pistol shot as a function of azimuth (0° azimuth is on-axis in front of the barrel, 180° is behind the shooting position).

 Colt M1911 45 shot

FIGURE 7: Recordings of a Glock 23 0.40 pistol shot as a function of azimuth (0° azimuth is on-axis in front of the barrel, 180° is behind the shooting position).

 Glock 23 0.40 pistol shot

FIGURE 8:  Recordings of a Sig 239 0.357 caliber pistol shot as a function of azimuth (0° azimuth is on-axis in front of the barrel, 180° is behind the shooting position).

 sig 239 357

 

FIGURE 9:  Recordings of a Ruger SP101 .38 caliber revolver shot as a function of azimuth (0° azimuth is on-axis in front of the barrel, 180° is behind the shooting position).

sp101 38

 

 

FIGURE 10:  Recordings of a .22 caliber long rifle shot as a function of azimuth (0° azimuth is on-axis in front of the barrel, 180° is behind the shooting position).

22 rifle