A 3D formulation of inverse synthetic aperture (ISAR) is presented showing how the various geometry and motion parameters determine the image generation properties. We then show how the arbitrary formatting capability...
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ISBN:
(纸本)0819419214
A 3D formulation of inverse synthetic aperture (ISAR) is presented showing how the various geometry and motion parameters determine the image generation properties. We then show how the arbitrary formatting capability of an opto-electronic processor can be used to format the data in such a way as to focus the image. The focusing parameters are found from tracking prominent points in the radar data itself and using rigid body constraints imposed on the data. The opto-electronic processor is particularly suited for generated image data such as found with ISAR. The processor is a time-integrating architecture that uses acousto-optic scanners for arbitrary formatting and a modified Kosters interferometer for stable Fourier transformation. This research is being funded by the Office of Naval Research.
Mathematical morphology, as originally described by Matheron and Serra, consists of the application of set theoretical operations between the image set x and a structure element set B. image skeletons are very efficie...
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ISBN:
(纸本)0819418447
Mathematical morphology, as originally described by Matheron and Serra, consists of the application of set theoretical operations between the image set x and a structure element set B. image skeletons are very efficient representations of shape, and can be directly derived using the morphological operations of erode and open. If done at full image resolution, derivation of a skeleton can be very time consuming without dedicated signalprocessing hardware. This paper presents an alternative to the standard approach that relies on morphological operations within the wavelet coefficient space. In particular, the skeleton transformation can be done very efficiently at the reduced resolution of the coarse wavelet coefficient levels. We investigate the relationship between wavelet image compression and morphological transforms for the derivation of skeletons. We also report the results of some experimental studies on binary and gray scale images.
Malvar wavelets or lapped orthogonal transform (LOT) has been recognized as a useful tool in eliminating blocking effects in transform coding. Recently, it has been also extended to more general forms, which enable on...
In recent years there has been a great deal of interest in the use of wavelets to supplement or replace conventional Fourier transform signalprocessing. This paper provides a review of wavelet transforms for signal p...
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ISBN:
(纸本)0819420131
In recent years there has been a great deal of interest in the use of wavelets to supplement or replace conventional Fourier transform signalprocessing. This paper provides a review of wavelet transforms for signalprocessingapplications, and discusses several emerging applications which benefit from the advantages of wavelets. The wavelet transform can be implemented as an acousto-optic correlator;perfect reconstruction of digital signals may also be achieved using acousto-optic finite impulse response filter banks. Acousto-optic image correlators are discussed as a potential implementation of the wavelet transform, since a 1D wavelet filter bank may be encoded as a 2D image. We discuss applications of the wavelet transform including nondestructive testing of materials, biomedical applications in the analysis of EEG signals, and interference excision in spread spectrum communication systems. Computer simulations and experimental results for these applications are also provided.
This paper describes a simple method for retrieving images from image databases by a similarity retrieval scheme. With wavelets feature vectors are defined, which `measure the presence' of structures of variable s...
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ISBN:
(纸本)0819419281
This paper describes a simple method for retrieving images from image databases by a similarity retrieval scheme. With wavelets feature vectors are defined, which `measure the presence' of structures of variable size and orientation;moreover corresponding feature vectors providing a multiresolution analysis of object contours are developed. The significance of these feature vectors for classifying images as `similar' is verified on a set of medical MR- images. Based on these experiments a scheme for retrieving MR-images from databases can be defined and typical retrieval results are reported.
In this paper, we investigate the performance of baseband modems based on biorthogonal and semiorthogonal wavelets and compare their performance in terms of bandwidth efficiency and bit-error-rate with orthogonal wave...
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ISBN:
(纸本)0819419281
In this paper, we investigate the performance of baseband modems based on biorthogonal and semiorthogonal wavelets and compare their performance in terms of bandwidth efficiency and bit-error-rate with orthogonal wavelet based systems and conventional polar signalling schemes. The proposed modems are shown to conserve bandwidth at the cost of increased per-bit signal to noise ratio.
This paper looks at a novel technique for designing wavelets. Based only on orthonormality, the technique exploits the degrees of freedom in discrete wavelets when the Strang accuracy conditions are abandoned. For an ...
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ISBN:
(纸本)0819418447
This paper looks at a novel technique for designing wavelets. Based only on orthonormality, the technique exploits the degrees of freedom in discrete wavelets when the Strang accuracy conditions are abandoned. For an N order matrix, orthonormality guarantees perfect reconstruction when compression is not used, and N/2 equations remain for specifying the new wavelets. Classically the moment conditions provide polynomial accuracy to degree N/2 - 1. By not using the Strang accuracy conditions, reconstruction degrades more quickly for smooth images, but more slowly for irregular images. One dimensional signals are considered, as well as black and white images using a gray scale range of 256 on 128 x 128 pixels. For this discussion, 2 dimensional images are treated by 1 dimensional slicing. The transform process is that of Mallat forward and backward transformations with compression affected in the usual way by coefficient chopping. The novel feature is the departure from Strang's accuracy conditions.
Adapted wave form analysis, refers to a collection of FFT like adapted transform algorithms. Given an image these methods provide special matched collections of templates (orthonormal bases) enabling an efficient codi...
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ISBN:
(纸本)0819419265
Adapted wave form analysis, refers to a collection of FFT like adapted transform algorithms. Given an image these methods provide special matched collections of templates (orthonormal bases) enabling an efficient coding of the image. Perhaps the closest well known example of such coding method is provided by musical notation, where each segment of music is represented by a musical score made up of notes (templates) characterised by their duration, pitch, location and amplitude, our method corresponds to transcribing the music in as few notes as possible. The extension to images and video is straightforward we describe the image by collections of oscillatory patterns (paint brush strokes)of various sizes locations and amplitudes using a variety of orthogonal bases. These selected basis functions are chosen inside predefined libraries of oscillatory localized functions (trigonometric and wavelet-packets waveforms) so as to optimize the number of parameters needed to describe our object. These algorithms are of complexity N log N opening the door for a large range of applications in signal and imageprocessing, such as compression, feature extraction denoising and enhancement. In particular we describe a class of special purpose compressions for fingerprint irnages, as well as denoising tools for texture and noise extraction. We start by relating traditional Fourier methods to wavelet, wavelet-packet based algorithms using a recent refinement of the windowed sine and cosine transforms. We will then derive an adapted local sine transform show it's relation to wavelet and wavelet-packet analysis and describe an analysis toolkit illustrating the merits of different adaptive and nonadaptive schemes.
We construct a multiresolution analysis and wavelets on the manifolds S2 and SO(3). For C1-functions on S2 we derive the differentiability conditions for the singular points of their coordinate representation dependin...
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ISBN:
(纸本)0819419281
We construct a multiresolution analysis and wavelets on the manifolds S2 and SO(3). For C1-functions on S2 we derive the differentiability conditions for the singular points of their coordinate representation depending on polar coordinates. This leads in a natural way to tensor products of E-spline wavelets and wavelets on the interval. By using quaternion parameterization the case of SO(3) is reduced to the case of S3, which can be dealt with in the same way as S2 using a special parameterization.
The joint University of Rochester/Rochester Institute of Technology `Center for Electronic Imaging Systems' (CEIS) is designed to focus on research problems of interest to industrial sponsors, especially the Roche...
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ISBN:
(纸本)0819418447
The joint University of Rochester/Rochester Institute of Technology `Center for Electronic Imaging Systems' (CEIS) is designed to focus on research problems of interest to industrial sponsors, especially the Rochester Imaging Consortium. Compression of tactical images for transmission over an rf link is an example of this type of research project which is being worked on in collaboration with one of the CEIS sponsors, Harris Corporation/RF Communications. The Harris digital video imagery transmission system (DVITS) is designed to fulfill the need to transmit secure imagery between unwired locations at real-time rates. DVITS specializes in transmission systems for users who rely on hf equipment operating at the low end of the frequency spectrum. However, the inherently low bandwidth of hf combined with transmission characteristics such as fading and dropout severely restrict the effective throughput. The problem at designing a system such as DVITS is particularly challenging because of bandwidth and signal/noise limitations, and because of the dynamic nature of the operational environment. In this paper, a novel application of wavelets in tactical image coding is proposed to replace the current DCT compression algorithm in the DVITS system. THe effects of channel noise on the received image are determined and various design strategies combining image segmentation, compression, and error correction are described.
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