SpiderCam: Low-Power Snapshot Depth from Differential Defocus
This enables low-power 3D imaging for applications like robotics or mobile devices, though it is incremental as it builds on existing depth-from-defocus methods.
The authors tackled the problem of real-time depth sensing with low power consumption by developing SpiderCam, a camera that captures two differently focused images and processes them on an FPGA to produce 480x400 sparse depth maps at 32.5 FPS over 52 cm, consuming only 624 mW.
We introduce SpiderCam, an FPGA-based snapshot depth-from-defocus camera which produces 480x400 sparse depth maps in real-time at 32.5 FPS over a working range of 52 cm while consuming 624 mW of power in total. SpiderCam comprises a custom camera that simultaneously captures two differently focused images of the same scene, processed with a SystemVerilog implementation of depth from differential defocus (DfDD) on a low-power FPGA. To achieve state-of-the-art power consumption, we present algorithmic improvements to DfDD that overcome challenges caused by low-power sensors, and design a memory-local implementation for streaming depth computation on a device that is too small to store even a single image pair. We report the first sub-Watt total power measurement for passive FPGA-based 3D cameras in the literature.