In this paper, several state-of-the-art noise reduction algorithms are ranked using both subjective evaluation and 20 objective measures proposed in literature. It is found that no regression model based on these obje...
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ISBN:
(纸本)0780376226
In this paper, several state-of-the-art noise reduction algorithms are ranked using both subjective evaluation and 20 objective measures proposed in literature. It is found that no regression model based on these objective quality measures can replace subjective assessment.
In this paper we show how to use holographic photon echoes for the implementation of a variety of optical processing functions, including scanners, spectrum analyzers, time-integrating correlators, folded spectrum ana...
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ISBN:
(纸本)0819432903
In this paper we show how to use holographic photon echoes for the implementation of a variety of optical processing functions, including scanners, spectrum analyzers, time-integrating correlators, folded spectrum analyzers, ambiguity function processors, image sequence correlators, and folded image raster correlators. The combination of optical coherent transients operating as spatial-spectral holograms with acoustooptic deflectors and electrooptic modulators allows a variety of optical architectures to be implemented with substantially enhanced performance and functionality beyond that achievable by these technologies individually We show how to utilize the basic architectures presented here as building blocks of more powerful and complex real-time optical processingsystems.
Linear features from airport images correspond to runways, taxiways and roads. Detecting runways helps pilots to focus on runway incursions in poor visibility conditions. In this work, we attempt to detect linear feat...
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ISBN:
(纸本)0819462659
Linear features from airport images correspond to runways, taxiways and roads. Detecting runways helps pilots to focus on runway incursions in poor visibility conditions. In this work, we attempt to detect linear features from LiDAR swath in near real time using parallel implementation on G5-based apple cluster called Xseed. Data from LiDAR swath is converted into a uniform grid with nearest neighbor interpolation. The edges and gradient directions are computed using standard edge detection algorithms such as Canny's detector. Edge linking and detecting straight-line features are described. Preliminary results on Reno, Nevada airport data are included.
This paper presents an analytical performance prediction model and methodology that can be used to predict the execution time, speedup, scalability and similar performance metrics of a targe set of imageprocessing op...
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This paper presents an analytical performance prediction model and methodology that can be used to predict the execution time, speedup, scalability and similar performance metrics of a targe set of imageprocessing operations running on a p-processor parallel system. The model which requires only a few parameters obtainable on a minimal system can help in the systematic design, evaluation and performance tuning of parallel imageprocessingsystems. Using the model one can reason about the performance of a parallel imageprocessing system prior to implementation. The method can also support programmers in detecting critical parts of an implementation and system designers in predicting hardware performance and the effect of hardware parameter changes on performance. The execution of parallel imageprocessing operations was studied and operations were arranged in three main problem classes based on data locality and the communication patterns of the algorithms. The core of the method is the derivation of the overhead function, as it is the overhead that determines the achievable speedup. The overheads were examined and modelled for each class. The use of the method is illustrated by four class-representative imageprocessingalgorithms: image-scalar addition, convolution, histogram calculation and the Fast Fourier Transform. The developed performance model has been validated on a 16-node parallel machine and it has been shown that the model is able to predict the parallel run-time and other performance metrics of parallel imageprocessing operations accurately.
Signal, image and Synthetic Aperture Radar imagery algorithms in recent time are used in a daily routine. Due to huge data and complexity, their processing is almost impossible in a real time. Often imageprocessing a...
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ISBN:
(纸本)9781538669792
Signal, image and Synthetic Aperture Radar imagery algorithms in recent time are used in a daily routine. Due to huge data and complexity, their processing is almost impossible in a real time. Often imageprocessingalgorithms are inherently parallel in nature, so they fit nicely into parallel architectures multicore Central processing Unit (CPU) and Graphics processing Unit GPUs. In this paper imageprocessingalgorithms were evaluated, which are capable to execute in parallel manner on several platforms CPU and GPU. All algorithms were tested in TensorFlow, which is a novel framework for deep learning, but also for imageprocessing. Relative speedups compared to CPU were given for all algorithms. TensorFlow GPU implementation can outperform multi-core CPUs for tested algorithms, obtained speedups range from 3.6 to 15 times.
A robust version of Lee local statistic filter able to effectively suppress the mixed multiplicative and impulse noise in images is proposed. The performance of the proposed modification is studied for a set of test i...
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ISBN:
(纸本)0819452017
A robust version of Lee local statistic filter able to effectively suppress the mixed multiplicative and impulse noise in images is proposed. The performance of the proposed modification is studied for a set of test images, several values of multiplicative noise variance, Gaussian and Rayleigh probability density functions of speckle, and different characteristics of impulse noise. The advantages of the designed filter in comparison to the conventional Lee local statistic filter and some other filters able to cope with mixed multiplicative+impulse noise are demonstrated.
This paper discusses the postflight ground processingalgorithms for the Midcourse Space Experiment (MSX) Spatial Infrared Imaging Telescope (SPIRIT) iii radiometer data. The algorithm suite consists of image processi...
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ISBN:
(纸本)0819415367
This paper discusses the postflight ground processingalgorithms for the Midcourse Space Experiment (MSX) Spatial Infrared Imaging Telescope (SPIRIT) iii radiometer data. The algorithm suite consists of imageprocessing and object tracking that produces object histories for postflight signature studies. The imageprocessing is centered around least squares estimators for single and multiple objects for classification and characterization of object parameters. Object-tracking algorithms are implemented to support association of objects across multiple scans by utilizing an adaptive nearest neighbor association technique. A discussion of the design requirements and performance of the implemented algorithms will be presented.
We consider the recently proposed double phase encoding system, and we analyze the influence of a perturbation of the coded image on the decoded image. Since in optical implementations, the intensity of the decoded im...
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ISBN:
(纸本)0819432903
We consider the recently proposed double phase encoding system, and we analyze the influence of a perturbation of the coded image on the decoded image. Since in optical implementations, the intensity of the decoded image is measured at the output of the decoding system, we express the signal-to-noise ratio (SNR) on the intensity decoded image as a fonction of the amplitude SNR of the complex coded image. We show that there exists a simple relation between these two SNR's, and that this relation is quasi-independent of the nature of the coded image perturbation. The results presented in this paper could help characterizing the precision level of the components of the optical decoding system necessary to reach a pre-defined quality level of the decoded image.
The first and most important link of the crop shear optimization system, profile tracking and recognition (PTR) for hot bar ends, is introduced in this paper. Several features in system architecture are described. In ...
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ISBN:
(纸本)081941543X
The first and most important link of the crop shear optimization system, profile tracking and recognition (PTR) for hot bar ends, is introduced in this paper. Several features in system architecture are described. In the design of software, several ways are proposed to speed up the processing. A unique set of algorithms for real-time image data processing in C language and assembler language is used. Different thresholding strategy in different position are useful for the system to be used in a hostile environment and with scales on the bar. Experimental results show that the system has high reliability and good anti-interference performances.
Assessment of the resolution properties of nonlinear imaging systems is a useful but challenging task. While the modulation transfer function (MTF) fully describes contrast resolution as a function of spatial frequenc...
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ISBN:
(纸本)9780819494429
Assessment of the resolution properties of nonlinear imaging systems is a useful but challenging task. While the modulation transfer function (MTF) fully describes contrast resolution as a function of spatial frequency for linear systems, an equivalent metric does not exist for systems with significant nonlinearity. Therefore, this preliminary investigation attempts to classify and quantify the amount of scaling and distortion imposed on a given image signal as the result of a nonlinear process (nonlinear imageprocessing algorithm). As a proof-of-concept, a median filter is assessed in terms of its principle frequency response (PFR) and distortion response (DR) functions. These metrics are derived in frequency space using a sinusoidal basis function, and it is shown that, for a narrow-band sinusoidal input signal, the scaling and distortion properties of the nonlinear filter are described exactly by PFR and DR, respectively. The use of matched sinusoidal basis and input functions accurately reveals the frequency response to long linear structures of different scale. However, when more complex (multi-band) input signals are considered, PFR and DR fail to adequately characterize the frequency response due to nonlinear interaction effects between different frequency components during processing. Overall, the results reveal the context-dependent nature of nonlinear imageprocessing algorithm performance, and they emphasize the importance of the basis function choice in algorithm assessment. In the future, more complex forms of nonlinear systems analysis may be necessary to fully characterize the frequency response properties of nonlinear algorithms in a context-dependent manner
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