Title
Block-matching optical flow for dynamic vision sensors: Algorithm and FPGA implementation
Abstract
Rapid and low power computation of optical flow (OF) is potentially useful in robotics. The dynamic vision sensor (DVS) event camera produces quick and sparse output, and has high dynamic range, but conventional OF algorithms are frame-based and cannot be directly used with event-based cameras. Previous DVS OF methods do not work well with dense textured input and are designed for implementation in logic circuits. This paper proposes a new block-matching based DVS OF algorithm which is inspired by motion estimation methods used for MPEG video compression. The algorithm was implemented both in software and on FPGA. For each event, it computes the motion direction as one of 9 directions. The speed of the motion is set by the sample interval. Results show that the Average Angular Error can be improved by 30% compared with previous methods. The OF can be calculated on FPGA with 50 MHz clock in 0.2 us per event (11 clock cycles), 20 times faster than a Java software implementation running on a desktop PC. Sample data is shown that the method works on scenes dominated by edges, sparse features, and dense texture.
Year
DOI
Venue
2017
10.1109/ISCAS.2017.8050295
2017 IEEE International Symposium on Circuits and Systems (ISCAS)
Keywords
DocType
Volume
dynamic vision sensors,FPGA implementation,robotics,event-based cameras,logic circuits,block-matching based DVS OF algorithm,motion estimation methods,MPEG video compression,motion direction,Java software implementation,frequency 50 MHz
Conference
abs/1706.05415
ISSN
ISBN
Citations 
0271-4302
978-1-5090-1427-9
4
PageRank 
References 
Authors
0.40
8
2
Name
Order
Citations
PageRank
Min Liu15616.44
Tobi Delbrück287682.59