フォトニック時間伸長に着想を得た動画のリアルタイム動き検出
Real Time Motion Detection in Video Inspired by Photonic Time Stretch
光の時間伸長の物理原理を応用し、動画を画素ごとの時系列波形として扱うことで、高解像度のまま高速に動きの検出・増幅を行うアルゴリズムMoViDを提案した論文。
著者: Callen MacPhee, Yiming Zhou, Bahram Jalali
分類: cs.CV, eess.IV, physics.optics
原文アブストラクト
Motion perception is fundamental to computer vision and physical AI, and plays a central role in robotics, autonomous vehicles, human-computer interaction, and video compression. Traditional approaches such as background subtraction, frame-differencing and optical flow algorithms often struggle in complex or dynamic scenes, typically sacrificing spatial resolution for computational tractability. Here we introduce MoViD (Motion estimation via Virtual dispersion and phase Detection), a physics-inspired algorithm grounded in the principles that govern photonic time stretch - a highly successful ultrafast realtime data acquisition platform. Drawing inspiration from the optical physics therein, MoViD treats video as a collection of optical time series waveforms associated with pixels. Motion of an object through a pixel broadens the time series spectrum and, after group delay dispersion, induces a temporal phase that exists only if there is motion. Spatiotemporal group delay dispersion templates, corresponding to dielectric functions, classify specific motion trajectories. Unlike conventional empirical phase-based motion-analysis pipelines that require narrow-band spatial channelization and pyramid reconstruction, the physics-based MoViD operates directly on the broadband video signal, vastly increasing its computational speed. The resulting algorithm achieves unprecedented performance in both motion characterization and motion magnification, providing full-resolution motion mapping in real time at nearly 200 frames per second at 4K resolution and 70 frames per second for 8K video - orders of magnitude faster than classical optical flow approaches or learning-based methods. Notably, such extreme performance enables real time motion analysis at ultrahigh resolution for motion detection and compensation in robotics and other autonomous devices.