FlashBack is a system that leverages NVIDIA Cosmos-Reason2 to solve a critical fire safety challenge: tracing fire back to its origin from surveillance footage. Unlike existing systems that only detect whether a fire exists, FlashBack analyzes the fire spread process over time to infer where it started.
Surveillance camera frame sequences are converted into temporal video, then analyzed using Cosmos-Reason2's physics reasoning capabilities — flame propagation patterns, smoke dispersion dynamics, and convection-driven spread. By tracing these patterns in reverse chronological order, the system estimates the origin as both a text description ("bottom-left of the greenhouse") and precise image coordinates (x=0.25, y=0.75).
Core Innovation: Origin coordinates are visualized directly on the original frames — a red crosshair marks the predicted origin, yellow arrows indicate spread direction. Lucas-Kanade optical flow tracks the origin across frames as the camera moves, producing a tracked demo video.
Results: Across 11 fire scenes (FLAME/SMOKE/NORMAL), the system achieved 100% origin tracing rate and 100% temporal reasoning rate.
Physics Reasoning in Action: The model explains ignition points through convection patterns, fuel density correlations, and temporal spread characteristics, presenting its analysis step-by-step via Chain-of-Thought reasoning.