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- Astrom, Anders, et al.
(författare)
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Low-complexity, high-speed, and high-dynamic range time-to-impact algorithm
- 2012
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Ingår i: Journal of Electronic Imaging (JEI). - : Society of Photo-optical Instrumentation Engineers (SPIE). - 1017-9909 .- 1560-229X. ; 21:4
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Tidskriftsartikel (refereegranskat)abstract
- We present a method suitable for a time-to-impact sensor. Inspired by the seemingly "low" complexity of small insects, we propose a new approach to optical flow estimation that is the key component in time-to-impact estimation. The approach is based on measuring time instead of the apparent motion of points in the image plane. The specific properties of the motion field in the time-to-impact application are used, such as measuring only along a one-dimensional (1-D) line and using simple feature points, which are tracked from frame to frame. The method lends itself readily to be implemented in a parallel processor with an analog front-end. Such a processing concept [near-sensor image processing (NSIP)] was described for the first time in 1983. In this device, an optical sensor array and a low-level processing unit are tightly integrated into a hybrid analog-digital device. The high dynamic range, which is a key feature of NSIP, is used to extract the feature points. The output from the device consists of a few parameters, which will give the time-to-impact as well as possible transversal speed for off-centered viewing. Performance and complexity aspects of the implementation are discussed, indicating that time-to-impact data can be achieved at a rate of 10 kHz with todays technology.
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| 2. |
- Astrom, Anders, et al.
(författare)
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Statistical approach to time-to-impact estimation suitable for real-time near-sensor implementation
- 2022
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Ingår i: Journal of Electronic Imaging (JEI). - : SPIE-SOC PHOTO-OPTICAL INSTRUMENTATION ENGINEERS. - 1017-9909 .- 1560-229X. ; 31:6
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Tidskriftsartikel (refereegranskat)abstract
- We present a method to estimate the time-to-impact (TTI) from a sequence of images. The method is based on detecting and tracking local extremal points. Their endurance within and between pixels is measured, accumulated, and used to achieve the TTI. This method, which improves on an earlier proposal, is entirely different from the ordinary optical flow technique and allows for fast and low-complex processing. The method is inspired by insects, which have some TTI capability without the possibility to compute high-complex optical flow. The method is further suitable for near-sensor image processing architectures. (c) The Authors. Published by SPIE under a Creative Commons Attribution 4.0 International License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.
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