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EPICENTER — Open Analysis Pipeline

Audio-Visual Source Distance Analysis — State of Utah v. Tyler Robinson

Source videos, analysis code, and full methodology. Verify the results yourself.

Quick Start

pip install numpy scipy opencv-python matplotlib

python3 epicenter_pipeline.py --batch --video-dir . --validate --muzzle-blast

The Test

Count the video frames between the shirt expansion (light, instant) and the audio impulse (sound, 343 m/s). The FBI says 142 yards. That requires 11 frames of delay. We measured 0–2 frames.

Downloads

FileDescriptionSize
epicenter_pipeline.pyComplete analysis pipeline (Python 3)19 KB
README.mdFull documentation and methodology4 KB

Source Videos

FileEvent FrameFPSDurationSize
2.MOVF50759.9536.78s70 MB
IMG_6368.MOVF5529.997.36s9.2 MB
7.mp4F75929.9939.22s46 MB
1.mp4F5230.04.44s2.1 MB
13.mp4F24730.011.38s2.9 MB
Video2_1.mp4F6830.363.05s3.2 MB

How to Verify (No Code Required)

Open any video in VLC. Press E to step one frame at a time. Find the frame where the white shirt begins to expand. Find where the audio spike hits. Count the frames between them.

If the shot came from 142 yards, you should count 11 frames. You won't.

Results

RecordingFrames ApartΔTResult
IMG_6368.MOV0.27.5msEssentially simultaneous
2.MOV (60fps)1.118.3msBest precision measurement
1.mp42.170.6msWithin quantization error
7.mp42.274.5msWithin quantization error

— Jon Bray — followtheepicenter.com