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Frame synchronization of high-speed vision sensors with respect to temporally encoded illumination in highly dynamic environments.

Hou L, Kagami S, Hashimoto K - Sensors (Basel) (2013)

Bottom Line: Based on signal normalization, Manchester Encoded reference signals carry temporal information owing to serial communication and thus can timestamp the output vision frame.Both simulated and experimental results show satisfactory robustness to various disturbances, such as dynamic targets, fluctuant optical intensity, and unfixed cameras, etc.This result is believed to be applicable to low-cost wireless vision sensor network.

View Article: PubMed Central - PubMed

Affiliation: Department of Automation, Shanghai Jiao Tong University, and Key Laboratory of System Controland Information Processing, Ministry of Education of China, Shanghai 200240, China. lei@ic.is.tohoku.ac.jp

ABSTRACT
The authors propose a Manchester Encoding inspired illumination modulation strategy to properly index the temporally-aligned vision frames, which are successfully synchronized by the LED reference signal. Based on signal normalization, Manchester Encoded reference signals carry temporal information owing to serial communication and thus can timestamp the output vision frame. Both simulated and experimental results show satisfactory robustness to various disturbances, such as dynamic targets, fluctuant optical intensity, and unfixed cameras, etc. The 1,000 Hz vision sensor is locked to 500 Hz temporally modulated LED illumination with only 24 μs jitters. This result is believed to be applicable to low-cost wireless vision sensor network.

No MeSH data available.


The relations between time correlations and phase difference.
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f3-sensors-13-04102: The relations between time correlations and phase difference.

Mentions: The time correlation value q(ø) can be seen as a function of the relative phase difference ø shown in Figure 3 for the case with full exposure time. Here, the relative phase difference is defined to be zero when the midst time of the reference On period and the midst time of the integration period in the frame where g(t) = 1 coincide. By using the correlation q for feedback, the system can converge to the unique stable equilibrium point ø = π/2. By computing q in every frame, negative feedback control is done in real time.


Frame synchronization of high-speed vision sensors with respect to temporally encoded illumination in highly dynamic environments.

Hou L, Kagami S, Hashimoto K - Sensors (Basel) (2013)

The relations between time correlations and phase difference.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3673073&req=5

f3-sensors-13-04102: The relations between time correlations and phase difference.
Mentions: The time correlation value q(ø) can be seen as a function of the relative phase difference ø shown in Figure 3 for the case with full exposure time. Here, the relative phase difference is defined to be zero when the midst time of the reference On period and the midst time of the integration period in the frame where g(t) = 1 coincide. By using the correlation q for feedback, the system can converge to the unique stable equilibrium point ø = π/2. By computing q in every frame, negative feedback control is done in real time.

Bottom Line: Based on signal normalization, Manchester Encoded reference signals carry temporal information owing to serial communication and thus can timestamp the output vision frame.Both simulated and experimental results show satisfactory robustness to various disturbances, such as dynamic targets, fluctuant optical intensity, and unfixed cameras, etc.This result is believed to be applicable to low-cost wireless vision sensor network.

View Article: PubMed Central - PubMed

Affiliation: Department of Automation, Shanghai Jiao Tong University, and Key Laboratory of System Controland Information Processing, Ministry of Education of China, Shanghai 200240, China. lei@ic.is.tohoku.ac.jp

ABSTRACT
The authors propose a Manchester Encoding inspired illumination modulation strategy to properly index the temporally-aligned vision frames, which are successfully synchronized by the LED reference signal. Based on signal normalization, Manchester Encoded reference signals carry temporal information owing to serial communication and thus can timestamp the output vision frame. Both simulated and experimental results show satisfactory robustness to various disturbances, such as dynamic targets, fluctuant optical intensity, and unfixed cameras, etc. The 1,000 Hz vision sensor is locked to 500 Hz temporally modulated LED illumination with only 24 μs jitters. This result is believed to be applicable to low-cost wireless vision sensor network.

No MeSH data available.