Original Research ARTICLE
A Noise Filtering Algorithm for Event-Based Asynchronous Change detection Image Sensors and its Implementation on TrueNorth
- 1School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore
- 2Singapore Institute for Neurotechnology (SINAPSE), National University of Singapore, Singapore
Asynchronous event-based sensors, or “silicon retinae,” are a new class of vision sensors inspired by biological vision systems. The output of these sensors often contains a significant number of noise events along with the signal. Filtering these noise events is a common preprocessing step before using the data for tasks such as tracking and classification. This paper presents a novel spiking neural network-based approach to filtering noise events from data captured by an Asynchronous Time-based Image Sensor on a neuromorphic processor, the IBM TrueNorth Neurosynaptic System. The significant contribution of this work is that it demonstrates our proposed filtering algorithm not only outperforms the traditional nearest neighbour neighbour noise filter in achieving higher signal to noise ratio ( ~10 dB higher) and retaining the events related to signal (~3X more). In addition, for some parameters, it can also generate some of the missing events in the spatial neighbourhood of the signal for all classes of moving objects in the data which are unattainable using the nearest neighbour filter.
Keywords: TrueNorth, Neuromorphic vision, Noise filtering, Event-based camera, Silicon Retina, Neural Network
Received: 06 Nov 2017;
Accepted: 14 Feb 2018.
Edited by:Hongzhi You, University of Electronic Science and Technology of China, China
Reviewed by:Luping Shi, Tsinghua University, China
Xavier Clady, UMR7210 Institut de la Vision, France
Jiangtao Xu, Tianjin University, China
Copyright: © 2018 Padala, Basu and Orchard. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Prof. Arindam Basu, Nanyang Technological University, School of Electrical and Electronic Engineering, Singapore, Singapore, email@example.com