Risi Nicoletta, Aimar Alessandro, Donati Elisa, Solinas Sergio, Indiveri Giacomo
Institute of Neuroinformatics, University of Zurich, Eidgenössische Technische Hochschule Zurich, Zurich, Switzerland.
Front Neurorobot. 2020 Nov 13;14:568283. doi: 10.3389/fnbot.2020.568283. eCollection 2020.
The problem of finding stereo correspondences in binocular vision is solved effortlessly in nature and yet it is still a critical bottleneck for artificial machine vision systems. As temporal information is a crucial feature in this process, the advent of event-based vision sensors and dedicated event-based processors promises to offer an effective approach to solving the stereo matching problem. Indeed, event-based neuromorphic hardware provides an optimal substrate for fast, asynchronous computation, that can make explicit use of precise temporal coincidences. However, although several biologically-inspired solutions have already been proposed, the performance benefits of combining event-based sensing with asynchronous and parallel computation are yet to be explored. Here we present a hardware spike-based stereo-vision system that leverages the advantages of brain-inspired neuromorphic computing by interfacing two event-based vision sensors to an event-based mixed-signal analog/digital neuromorphic processor. We describe a prototype interface designed to enable the emulation of a stereo-vision system on neuromorphic hardware and we quantify the stereo matching performance with two datasets. Our results provide a path toward the realization of low-latency, end-to-end event-based, neuromorphic architectures for stereo vision.
双目视觉中寻找立体对应关系的问题在自然界中能轻松解决,但它仍是人工机器视觉系统的关键瓶颈。由于时间信息是这一过程中的关键特征,基于事件的视觉传感器和专用的基于事件的处理器的出现有望为解决立体匹配问题提供一种有效方法。实际上,基于事件的神经形态硬件为快速、异步计算提供了理想的基础,这种计算能够明确利用精确的时间巧合。然而,尽管已经提出了几种受生物启发的解决方案,但将基于事件的传感与异步和并行计算相结合的性能优势尚未得到探索。在此,我们展示了一种基于硬件脉冲的立体视觉系统,该系统通过将两个基于事件的视觉传感器与一个基于事件的混合信号模拟/数字神经形态处理器相连,利用了受大脑启发的神经形态计算的优势。我们描述了一个旨在能够在神经形态硬件上模拟立体视觉系统的原型接口,并使用两个数据集对立体匹配性能进行了量化。我们的研究结果为实现用于立体视觉的低延迟、端到端基于事件的神经形态架构提供了一条途径。