3D scene reconstruction from body-worn camera video using 3DF Zephyr.

Body-worn cameras document crime scenes during initial law enforcement response, yet their potential for forensic reconstruction has not been empirically validated. Despite expanding global adoption, recorded video primarily serves qualitative documentation rather than quantitative measurement applications. This study empirically evaluated three-dimensional (3D) reconstruction accuracy from body-worn camera video to assess its feasibility for feature measurement. Three Axon camera models-Body 2 (AB2), Flex 2 (AF2), and Body 3 (AB3)-were tested in an outdoor parking lot, with each model recording five videos at both 720P and 1080P resolutions (n = 30). Videos were recorded under controlled experimental conditions to achieve optimized documentation scenarios. Videos were processed using 3DF Zephyr photogrammetry software to create 3D reconstructions, then compared against Faro Focus S350 laser scanner ground truth at three distances: long (12.48 m), medium (2.42 m), and short (0.24 m). One-sample t-tests revealed significant differences between AF2 measurements and ground truth (p < 0.05), with a maximum mean error of 14.42 cm at 720P for long distances. AB2 and AB3 showed no significant differences from the ground truth at both resolutions across all validation distances (p ≥ 0.05). Two-sample t-tests demonstrated no significant differences between resolutions (p ≥ 0.05). Single-factor ANOVAs indicated significant differences between camera models (p < 0.05). Resolution did not affect measurement accuracy under the conditions of the controlled methodology and internal software interpolation. These best-case results demonstrate that with deliberate documentation protocols, accurate 3D reconstruction from body-worn camera video is achievable for forensic applications.