Protection against geometric distortions and common image processing operations has become a much challenging task in image watermarking. To achieve this, in this paper we propose a watermarking scheme based on Bessel...
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Protection against geometric distortions and common image processing operations has become a much challenging task in image watermarking. To achieve this, in this paper we propose a watermarking scheme based on Bessel-Fourier moment. Image normalization is adopted to construct the geometrically invariant space. Some suitable Bessel-Fourier moments are selected, and their magnitudes are quantized by odd-even quantization modulation to generate an array of bits for watermark. In watermark extraction, the same quantization parameter is used for odd-even quantization modulation. The magnitudes of the same selected Bessel-Fourier moments of the attacked image are quantized to extract the watermark sequence. Extensive simulation results show that the proposed algorithm is robust against various geometric attacks as well as common image processing operations and outperforms representative image watermarking schemes.
The nonlinear response and strong coupling of control channels of micro machined membrane deformable mirror (MMDM) devices make it difficult to obtain the desired optimal surface shape of the MMDM. In order to overcom...
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The nonlinear response and strong coupling of control channels of micro machined membrane deformable mirror (MMDM) devices make it difficult to obtain the desired optimal surface shape of the MMDM. In order to overcome these limitations, the wave front modal reconstruction algorithm based on particle swarm optimization (PSO) is proposed, which is used to find the optimal control voltages of the MMDM. It is initialized with a population of random solutions and searches for optima by updating generations. In this way the objective function can be optimum and influence of phase aberration can be reduced to minimum. The simulation results show that this algorithm could find the optimal MMDM shape which was applied to correct phase aberration.
Wavefront sensor-less adaptive optics is an important method for correcting wavefront aberration. An appropriate optimization algorithm is crucial to aberration correction. An improved particle swarm optimization (IPS...
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Wavefront sensor-less adaptive optics is an important method for correcting wavefront aberration. An appropriate optimization algorithm is crucial to aberration correction. An improved particle swarm optimization (IPSO) is presented which well addresses slow convergence rate and low calculation precision in the standard PSO. In IPSO, mutation strategies are adopted to keep the diversity of population and make particles explore the solution space efficiently. Based on these two algorithms, an adaptive optics system with a 37-element deformable mirror is established. The experimental results show that IPSO is better than SPSO in convergence rate, reconstruction performance and correction effect.
In order to eliminate noise in wavefront slope signals detected by a Hartmann wavefront sensor, a new denoising method was proposed by combining wavelet transform with modal reconstruction algorithm. The noise in the ...
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In order to eliminate noise in wavefront slope signals detected by a Hartmann wavefront sensor, a new denoising method was proposed by combining wavelet transform with modal reconstruction algorithm. The noise in the signals was removed by wavelet transform. The residual noise then was removed from the signals by using modal reconstruction algorithm. By practical application and simulation test, it was proved that this method could eliminate noise efficiently from wavefront slope signals during wavefront detection. The method that combines wavelet transform and modal reconstruction algorithm can be used for wavefront slope signals denoising.
The object-oriented simulation software of an adaptive optics system is used to evaluate the performance of the adaptive optics system. The software includes distorted wavefront correction and turbulence simulation. A...
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The object-oriented simulation software of an adaptive optics system is used to evaluate the performance of the adaptive optics system. The software includes distorted wavefront correction and turbulence simulation. An object-oriented adaptive optics system framework is proposed based on the features of adaptive optics systems simulation. Numerical simulation results show that it is a valid numerical simulation software.
The light spot image of linear CCD is a kind of the representative peak signal. During filtering, it is difficult to suppress noise and preserve the peak features as much as possible. The position, amplitude, area, ed...
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This paper presents an industrial temperature measuring and monitoring system, which is based on 89C51 single chip microcontroller, and details the comparison between Formula method and Look-up Table method whose new ...
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This paper presents an industrial temperature measuring and monitoring system, which is based on 89C51 single chip microcontroller, and details the comparison between Formula method and Look-up Table method whose new algorithm and high precision has been emphasized. The system can measure real-time industrial temperature, store historical data and display temperature in digital and curve diagram. MAX6675 is applied in temperature acquisition module, which simplifies the system design and improve measuring precision. The data analysis methods and circuit design are given in paper. It is proved that the design is stable, reliable, simple and durable.
The quality of virtual view based on multi-view video （MVD） plus depth format is often evaluated by PSNR or subjectively judged. However, due to synthesizing arbitrary view images, the virtual view images mostly hav...
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The quality of virtual view based on multi-view video （MVD） plus depth format is often evaluated by PSNR or subjectively judged. However, due to synthesizing arbitrary view images, the virtual view images mostly have no reference images and are only assessed using non-reference. Virtual view images synthesized by depth estimation reference software （DERS） and view synthesis reference software （VSRS） often accompanied with blockiness and other distortions on the edge. In addition, matching level for the depth map and the corresponding texture maps of left and right views also affects the quality of the virtual view. This paper compares the edge similarity of the depth and the corresponding texture maps which generate the intermediate virtual view and combined with the virtual view＇s blockiness which causing blur to evaluate the quality of the virtual view. Experiment results show that the proposed method can reflect the quality of the virtual view better.
People's opinion collection and processing system (POCP) is the electronic petition system with the function of website, hot line, E-mail and short message service (SMS), which is developed for Fuzhou Municipal Co...
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People's opinion collection and processing system (POCP) is the electronic petition system with the function of website, hot line, E-mail and short message service (SMS), which is developed for Fuzhou Municipal Committee in JiangXi province. With the increasing demands of government service quality, the number of opinions brought by the masses is also on the increase. Seeking effective means and classifying these opinions to carry out contrapuntally become a gradually urgent problem. Based on the characteristic that SMS can change into text, this paper presents a thought that text classification algorithm can be used in the technology of SMS processing. SMS will be classified to different fields by preprocessing, feature section and classifier. At last, the reliable bases to government decision-making will be provided contrapuntally by analyzing the field classification of opinions.
A simple and powerful approach to sort out Direct Mail to be delivered intelligently without artificial identification is proposed, which makes a breakthrough at the automatic fragments and sequencing points of mailin...
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A simple and powerful approach to sort out Direct Mail to be delivered intelligently without artificial identification is proposed, which makes a breakthrough at the automatic fragments and sequencing points of mailing address. A series of rules are created on the analysis of the address characteristics to computerize its segmentations, provide their matching regulations to order mails intellectually, and even assess the reliability of sorting to reduce computer error as far as possible. The experiments indicate that the consequence is more accurate and spends much less time than traditional processes using large-scale sorting machine with zip code and manual labor picking.
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