A new real-time image-processing architecture for an electro-optical tracking system was developed and evaluated. In this architecture, the universal interface called Pipelined Data Interface (PDI) was defined, and th...
详细信息
ISBN:
(纸本)0819405922
A new real-time image-processing architecture for an electro-optical tracking system was developed and evaluated. In this architecture, the universal interface called Pipelined Data Interface (PDI) was defined, and this interface connects the function modules. The authors fabricated the equipment as a demonstration system, including an input section, SPU (support unit), and an imageprocessing section, IPU (imageprocessing unit). In the IPU various modules are realized. These modules include spatial filters, moving target detector, window thresholder, binary filters, shrink point finder, boundary tracer, feature extractor, ID (identification) filters, etc.
A modular signal processor architecture suitable for many applications has been developed to meet real-time requirements, and is adaptable to multiple uses. This generic modular architecture has been developed and dem...
详细信息
ISBN:
(纸本)0819405922
A modular signal processor architecture suitable for many applications has been developed to meet real-time requirements, and is adaptable to multiple uses. This generic modular architecture has been developed and demonstrated in real-time hardware for representative filters and a target detection algorithm. Computer-aided design tools were used throughout the hardware development, and an application specific integrated circuit (ASIC) or other custom IC implementation could be used for actual production hardware.
A new opening operation (NOP) and a new closing operation (NCP) are introduced and the algorithms to effectively compute the NOP and the NCP are developed. Based on the NOP and the NCP algorithms, an adaptive morpholo...
详细信息
ISBN:
(纸本)0819405922
A new opening operation (NOP) and a new closing operation (NCP) are introduced and the algorithms to effectively compute the NOP and the NCP are developed. Based on the NOP and the NCP algorithms, an adaptive morphological filter is constructed. The filter adapts to the change of the image features in a way that it finds the optimal shape of the local structuring element of the filter according to the local features of the image. The shape can be any connected shape of a given size, which is considered the best to preserve the local details of the image. In that way, the filter can preserve any details larger or equal to the given mask size and remove those of smaller size. The local computational complexity of the filter changes according to the complexity of the local features of the image. Experiments have shown that the overall computational complexity of the proposed adaptive morphological filter is comparable to that of the nonadaptive one combining four 1-D structuring elements of the same size.
An adaptive optical system dedicated to high resolution imaging can be modeled in terms of transfer loops. This model permits estimation of the response of such a system to time-varying wavefront perturbation. A block...
详细信息
ISBN:
(纸本)0819405922
An adaptive optical system dedicated to high resolution imaging can be modeled in terms of transfer loops. This model permits estimation of the response of such a system to time-varying wavefront perturbation. A block diagram describing an adaptive optic as a closed loop system is given and an analytical expression expressed in Z transform is found. In a second step, identification methods are used;the best estimates for the parameter values of the model are found using as an example the Come_On project data. Finally the responses of the model to known perturbations are compared with the experimental data recorded during the experiments of Come_On;the results are found to be in good agreement.
This paper describes a computer-aided performanceevaluation system for testing and checking the on-board data compression system used in the High- Resolution Imaging Spectrometer (HIRIS). The earth resources spectra ...
详细信息
ISBN:
(纸本)0819405922
This paper describes a computer-aided performanceevaluation system for testing and checking the on-board data compression system used in the High- Resolution Imaging Spectrometer (HIRIS). The earth resources spectra from the NASA earth resources spectral information system are taken for simulative spectra of ground objects, and these spectra are sampled and quantized according to the conditions and parameters of HIRIS. Then the simulative spectral data are put in a GIFOV spectral data generator through a computer interface. In testing, the spectral data stored in the generator are sent to the data compression system at the same rate of the readout clock of subdetectors in HIRIS. The data compression system compresses the input data in real-time under the control of the clock of the input daCa. After compressing, the compression results are returned to the computer through a bidirection interface and compared with the original ones. Finally, the computer gives out testing results. This kind of test system can exactly simulate the original data obtained by HIRIS in space, and objectively evaluate the data compression system.
In a preceding paper the authors calculated the mean value of the Optical Transfer Function (OTF) for a high-resolution imaging instrument corrected by adaptive optics. The Come_On experiments carried out during 1990 ...
详细信息
ISBN:
(纸本)0819405922
In a preceding paper the authors calculated the mean value of the Optical Transfer Function (OTF) for a high-resolution imaging instrument corrected by adaptive optics. The Come_On experiments carried out during 1990 show good correlation with the mathematical model. In the present paper the model described in the 1987 paper is revised to introduce modal control and take into account the effects of time lags and/or angular depointings on the corrected OTF. These lags represent the time needed to perform the computations between phase measurements and corrections, and the angular depointings define the angular field where the corrections are valuable. The model permits an evaluation of the OTF decay in respect to the Fried diameter. Numerical results are given using the modified model with the Come_On project specifications. These works have been sponsored by the French Defense Ministry through the Direction des Recherches, Etudes et Techniques (DRET).
imagery is a critical need for ATR development. Real-world scenes collected for ATR training and testing typically attempt to sample various target types, contrasts, backgrounds, depression angles, and ranges. These d...
详细信息
ISBN:
(纸本)0819405922
imagery is a critical need for ATR development. Real-world scenes collected for ATR training and testing typically attempt to sample various target types, contrasts, backgrounds, depression angles, and ranges. These data sets are limited by the variability of the real world. ATR development is greatly enhanced by a data set that voids some of the real-world problems. The Terrain Board test facility of CECOM's Center for Night Vision and Electro-Optics (C2NVEO) has the resources to obtain such an image training set that voids some of these real-world problems. As part of the Balanced Technology Initiative Program (BTI), an extensive digital imagery set was recently collected at the facility, controlling some of the variables of the real world and systematically varying others.
The fusion of multi-sensor data is dependent upon a paradigm of evidence accumulation. Many methodologies presently exist to carry out this fusion process, but the advantages and problems involved with each are not we...
详细信息
ISBN:
(纸本)0819405922
The fusion of multi-sensor data is dependent upon a paradigm of evidence accumulation. Many methodologies presently exist to carry out this fusion process, but the advantages and problems involved with each are not well documented or quantified. A modeling tool has been developed for these processes. This tool allows a comparison of evidence accumulation algorithms such as Bayes Nets and a Fuzzy Set concept. The tool allows variation of the number of sets of evidence accumulated as well as the correlation between these sets. These sets are compared by using the same inputs which can be interpreted as either features, decisions, or evidence. The performance differences between the paradigms are measured. A baseline fusion process is developed which takes into account the full covariance matrix of the data, thus taking into account the correlation between the evidence sources. This problem is completely solved and compared to the solution of the methods which implicitly or explicitly make assumptions about the interrelationship of data sources, methods such as Bayes, Dempster-Shafer, and Fuzzy Sets. The results are given in parametric form which can be utilized to develop design decision tools for systems. This tool will allow comparisons of methods and measures of bounding errors using the paradigms based on assumptions. An outline is given as to the assumptions required for each of the methods and how these impact the type of data required. The results of a sensitivity analysis, which shows the significance of these results in evaluation methodologies, is discussed.
The authors present the performanceevaluation of a demand assignment multiple access (DAMA) scheme designed specifically for the mobile radio service (MRS) to be supported by the emerging mobile satellite systems (MS...
详细信息
ISBN:
(纸本)0879426381
The authors present the performanceevaluation of a demand assignment multiple access (DAMA) scheme designed specifically for the mobile radio service (MRS) to be supported by the emerging mobile satellite systems (MSSs). MRS caters mainly to private voice dispatch applications, where traffic is characterized by short holding time and fixed connectivity. The DAMA scheme makes use of call queuing, batch processing, and pipelined signaling to minimize call setup overhead for MRS traffic. Batching delay and channel assignment delay are investigated by simulationmodeling of many private dispatch networks operating over a multiple spot beam satellite. Traffic engineering issues are considered. A dynamic channel allocation scheme is devised to increase system capacity by sharing the DAMA channel pool between MRS and the mobile telephone service (MTS).
The authors offer transinformation maximization as the criterion for optimal signal quantization for most applications in lieu of the more conventional criteria, such as mean-square-error minimization first proposed b...
详细信息
ISBN:
(纸本)0819405922
The authors offer transinformation maximization as the criterion for optimal signal quantization for most applications in lieu of the more conventional criteria, such as mean-square-error minimization first proposed by Max. Optimal quantization for signal transinformation (which reduces to entropy in the noise-free case) using a uniform digitizer and a companding gain function is considered, and specifically applied to the image acquisition problem for ATR (Automatic Target Recognizer) processing. Both pre- and post-gain noisy channels are examined under linear sensor gain (with extension to non-linear gains);maximum achievable entropy, transinformation, SNR, and minimum mean square error are computed for several typical input distributions. The authors establish the following arguments supporting Maximum Transinformation Acquisition - MTA (noise) - and Maximum Entropy Acquisition - MEA (no-noise): (1) MTA 'matches' the sensor/digitizer channel to the input signal in an information-theoretic sense, preserving as much analog information as possible. (2) MTA can be closely approximated with a less computationally intensive algorithm than actual transinformation. (3) Net information content is the crucial quantity governing a priori detection and recognition in cluttered environments. (4) MEA provides the best overall pixel intensity spread throughout the image, maximizing the probability of pixel differences where analog intensities differ;MTA provides very near optimal SNR and noise- free pixel contrasts. (5) MTA provides a standard, repeatable, and globally optimal acquisition method for extracting information for ATRs in the absence of a priori scene knowledge;MTA can also be applied locally to maximize information content within a region of interest.
暂无评论