1995 Fiscal Year Final Research Report Summary
On the optimizing weighting problem in active image processing
Project/Area Number |
06650062
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Research Category |
Grant-in-Aid for General Scientific Research (C)
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Allocation Type | Single-year Grants |
Research Field |
Applied optics/Quantum optical engineering
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Research Institution | Osaka Electro-Communication University |
Principal Investigator |
IKUTA Takashi Osaka Electro-Communication Univ.Faculty of Engineering, Professor, 工学部, 教授 (20103343)
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Co-Investigator(Kenkyū-buntansha) |
KISHIOKA Kiyoshi Osaka Electro-Commujnication Univ.Faculty of Enigneering, Professor, 工学部, 教授 (50109881)
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Project Period (FY) |
1994 – 1995
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Keywords | Image processing / Active image processing / Modulation spectroscopy / Convolver / Weighting method / Time of stay weighting / Optimizing problem / Least mean square error criterion |
Research Abstract |
Previously, we have proposed a concept of the active (modulation) image processing method which is an extension of well known modulation spectroscopy, for 2-dimensional images. For both the active image processing and the modulation spectroscopy, integration operation is carried out after multiplication of a bipolar weighting funciton to observed image/signal, synchronized to the active modulation. To apply multiplication of the weighting function, two different weighting implementations are possible. First is a conventional numerical weighting, and next is a time-of-stay weighting. And both weighting implementations can be used together, while such combinaion results in different signal to noise {S/N} ratio for the processed images. In the present study, we have defined an optimizing weighting problem as to obtain optimized combination of these weighting implementations resulting maximum S/N ratio. At the first stage {1994} of the study, theoretical analysis has been aimed to the case in which the noise power is independent on the modulation or the signal. And we have got an exact solution using Schwarz's inequality. Namely, we obtain maximum S/N ratio when only the time-of-stay weighting is implemented in this simple case. In the next stage {1995}, we have applied a computer simulation of both weighting implementations to evaluate the S/N ratio under more complicated cases in which the noise power is dependent on the modulation or the signal. At same time we have continued to get an exact solution of such optimizing problem. And then we have successfully obtain an exact solution for such complicated case. This is `To implement the numerical weighting, as the noise power after the implementation of the numerical weighing is independent on the modulation', and then `To apply the time-of stay weighting to satisfy the whole weighting function'. This important result has been clearly well confirmed by the previous simulation.
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