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The Design and Use of Steerable Filters
 IEEE Transactions on Pattern Analysis and Machine Intelligence
, 1991
"... Oriented filters are useful in many early vision and image processing tasks. One often needs to apply the same filter, rotated to different angles under adaptive control, or wishes to calculate the filter response at various orientations. We present an efficient architecture to synthesize filters of ..."
Abstract

Cited by 1079 (11 self)
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Oriented filters are useful in many early vision and image processing tasks. One often needs to apply the same filter, rotated to different angles under adaptive control, or wishes to calculate the filter response at various orientations. We present an efficient architecture to synthesize filters of arbitrary orientations from linear combinations of basis filters, allowing one to adaptively "steer" a filter to any orientation, and to determine analytically the filter output as a function of orientation.
Perceptual image distortion
 In Proceedings of SPIE
, 1994
"... In this paper, we present a perceptual distortion measure that predicts image integrity far better than meansquared error. This perceptual distortion measure is based on a model of human visual processing that ts empirical measurements of the psychophysics of spatial pattern detection. The model of ..."
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Cited by 183 (0 self)
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In this paper, we present a perceptual distortion measure that predicts image integrity far better than meansquared error. This perceptual distortion measure is based on a model of human visual processing that ts empirical measurements of the psychophysics of spatial pattern detection. The model of human visual processing proposed involves two major components: a steerable pyramid transform and contrast normalization. We also illustrate the usefulness of the model in predicting perceptual distortion in real images. 1.
Subband Transforms
, 1990
"... this paper, the boxes H i #!# indicate circular convolution of a #nite input image of size N with a #lter with impulse response h i #n# and Fourier transform ..."
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Cited by 33 (8 self)
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this paper, the boxes H i #!# indicate circular convolution of a #nite input image of size N with a #lter with impulse response h i #n# and Fourier transform
Steerable Filters and Local Analysis of Image Structure
, 1992
"... Two paradigms for visual analysis are topdown, starting from highlevel models or information about the image, and bottomup, where little is assumed about the image or objects in it. We explore a local, bottomup approach to image analysis. We develop operators to identify and classify image junct ..."
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Cited by 31 (0 self)
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Two paradigms for visual analysis are topdown, starting from highlevel models or information about the image, and bottomup, where little is assumed about the image or objects in it. We explore a local, bottomup approach to image analysis. We develop operators to identify and classify image junctions, whichcontain important visual cues for identifying occlusion, transparency, and surface bends. Like the human visual system, we begin with the application of linear filters which are oriented in all possible directions. Wedevelop an efficientway to create an oriented filter of arbitrary orientation by describing it as a linear combination of basis filters. This approach to oriented filtering, which we call steerable filters, offers advantages for analysis as well as computation. We design a variety of steerable filters, including steerable quadrature pairs, which measure local energy. We show applications of these filters in orientation and texture analysis, and image representation and enhanc...
Pyramid Coding For Image And Video Compression
, 1994
"... This research investigates the use of pyramid coding in various digital image and video compression applications, the progressive transmission of images, and the efficient ecovery of motion information from video sequences. Through the use of feedback, pyramid coding allows both flexibility in th c ..."
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This research investigates the use of pyramid coding in various digital image and video compression applications, the progressive transmission of images, and the efficient ecovery of motion information from video sequences. Through the use of feedback, pyramid coding allows both flexibility in th choice of filters, and the use of quantization noise feedback. While the filters have a significant effect on the properties of the generated pyramid, quantization feedbackallows more control over the distortion introduced indirectly into the reconstructed image through separate quantization of the pyramid subimages. After a frequency domain analysis of pyramid coding, a new class of decimation and interpolation filters is developed. The use of both different filters, and quantization feedback in various applications is then explored. This is followed by proposals regarding possible choices of generation schemes and filters for the efficient implementation of pyramid coding in these applications. Finally, the performance of the pyramid codec is evaluated against both optimal methods, where appropriate, and other proposed suboptimal methods. For example, a filter pair is proposed for lossless image coding that not only leads to the generation of low entropy pyramids, but also allows a given image to be represented as a subsampled pyramid of the same number of pixels. Lossless compression ratios significantly higher than in the case of related techniques are achieved by this form of pyramid coding, while generally at a fraction of the computational cost. Appropriate filters are also proposed for the generation of pyramids suitable for the recovery of motion information from video sequences. Using hierarchical motion field recovery, based on pyramids generated with these filters, it i...
DEDICATION GLOBAL SEARCH METHODS FOR SOLVING NONLINEAR OPTIMIZATION PROBLEMS
"... In this thesis, we present new methods for solving nonlinear optimization problems. These problems are di cult to solve because the nonlinear constraints form feasible regions that are di cult to nd, and the nonlinear objectives contain local minima that trap descenttype search methods. In order to ..."
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In this thesis, we present new methods for solving nonlinear optimization problems. These problems are di cult to solve because the nonlinear constraints form feasible regions that are di cult to nd, and the nonlinear objectives contain local minima that trap descenttype search methods. In order to nd good solutions in nonlinear optimization, we focus on the following two key issues: how to handle nonlinear constraints and how to escape from local minima. We use a Lagrangemultiplierbased formulation to handle nonlinear constraints, and develop Lagrangian methods with dynamic control to provide faster and more robust convergence. We extend the traditional Lagrangian theory for the continuous space to the To my wife Lei, my parents, and my son Charles discrete space and develop e cient discrete Lagrangian methods. To overcome local minima, we design a new tracebased globalsearch method that relies on an external traveling trace to pull a search trajectory out of a local optimum in a continuous fashion without having to restart the search from a new starting point. Good starting points identi ed in the global search are used in the local search to identify true local optima. By combining these new methods, we develop a prototype, called Novel (Nonlinear Optimization Via External Lead),
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"... this paper, the boxes H i #!# indicate circular convolution of a #nite input image of size N with a #lter with impulse response h i #n# and Fourier transform H i #!#= h i #n#e #j!n We do not place a causality constraint on the #lter impulse responses, since they are meant for application to im ..."
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this paper, the boxes H i #!# indicate circular convolution of a #nite input image of size N with a #lter with impulse response h i #n# and Fourier transform H i #!#= h i #n#e #j!n We do not place a causality constraint on the #lter impulse responses, since they are meant for application to images. We do, however, assume that the region of support of the #lter is smaller than the image size. The boxes k i indicate that the sequence is subsampled by a factor of k i where k i is an integer for all i. The boxes k i indicate that the sequence should be upsampled by inserting k i 1 zeros between each sample. We will assume that the integers k i are divisors of N
Subband Transforms
"... Linear transforms are the basis for many techniques used in image processing, image analysis, and image coding. Subband transforms are a subclass of linear transforms which o er useful properties for these applications. In this chapter, we discuss a variety ofsubband decompositions and illustrate th ..."
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Linear transforms are the basis for many techniques used in image processing, image analysis, and image coding. Subband transforms are a subclass of linear transforms which o er useful properties for these applications. In this chapter, we discuss a variety ofsubband decompositions and illustrate their use in image coding. Traditionally, coders based on linear transforms are divided into two categories: transform coders and subband coders. This distinction is due in part to the nature of the computational methods used for the two types of representation. Transform coding techniques are usually based on orthogonal linear transforms. The classic example of such atransform is the discrete Fourier transform (DFT), which decomposes a signal into sinusoidal frequency components. Two other examples are the discrete cosine transform (DCT) and the KarhunenLoeve transform (KLT). Conceptually, these transforms are computed by taking the inner product of the nitelength signal with a set of basis functions. This produces a set of coe cients, which are then passed on to the
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"... Waveletbased denoising methods. A comparative study with applications in microscopy ..."
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Waveletbased denoising methods. A comparative study with applications in microscopy