Cross-Spectral Gated-RGB Stereo Depth Estimation

Abstract

Gated cameras flood-illuminate a scene and capture the time-gated impulse response of a scene. By employing nanosecond-scale gates existing sensors are capable of capturing mega-pixel gated images delivering dense depth improving on today's LiDAR sensors in spatial resolution and depth precision. Although gated depth estimation methods deliver a million of depth estimates per frame their resolution is still an order below existing RGB imaging methods. In this work we combine high-resolution stereo HDR RCCB cameras with gated imaging allowing us to exploit depth cues from active gating multi-view RGB and multi-view NIR sensing -- multi-view and gated cues across the entire spectrum. The resulting capture system consists only of low-cost CMOS sensors and flood-illumination. We propose a novel stereo-depth estimation method that is capable of exploiting these multi-modal multi-view depth cues including the active illumination that is measured by the RCCB camera when removing the IR-cut filter. The proposed method achieves accurate depth at long ranges outperforming the next best existing method by 39% for ranges of 100 to 220 m in MAE on accumulated LiDAR ground-truth. Our code models and datasets are available here (https://light.princeton.edu/gatedrccbstereo/).