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Thresholding of statistical maps in functional neuroimaging using the false discovery rate.

by Christopher R Genovese , Nicole A Lazar , Thomas Nichols - NeuroImage , 2002
"... Finding objective and effective thresholds for voxelwise statistics derived from neuroimaging data has been a long-standing problem. With at least one test performed for every voxel in an image, some correction of the thresholds is needed to control the error rates, but standard procedures for mult ..."
Abstract - Cited by 521 (9 self) - Add to MetaCart
Finding objective and effective thresholds for voxelwise statistics derived from neuroimaging data has been a long-standing problem. With at least one test performed for every voxel in an image, some correction of the thresholds is needed to control the error rates, but standard procedures

Stochastic relaxation, Gibbs distributions and the Bayesian restoration of images.

by Stuart Geman , Donald Geman - IEEE Trans. Pattern Anal. Mach. Intell. , 1984
"... Abstract-We make an analogy between images and statistical mechanics systems. Pixel gray levels and the presence and orientation of edges are viewed as states of atoms or molecules in a lattice-like physical system. The assignment of an energy function in the physical system determines its Gibbs di ..."
Abstract - Cited by 5126 (1 self) - Add to MetaCart
Abstract-We make an analogy between images and statistical mechanics systems. Pixel gray levels and the presence and orientation of edges are viewed as states of atoms or molecules in a lattice-like physical system. The assignment of an energy function in the physical system determines its Gibbs

Snakes, Shapes, and Gradient Vector Flow

by Chenyang Xu, Jerry L. Prince - IEEE TRANSACTIONS ON IMAGE PROCESSING , 1998
"... Snakes, or active contours, are used extensively in computer vision and image processing applications, particularly to locate object boundaries. Problems associated with initialization and poor convergence to boundary concavities, however, have limited their utility. This paper presents a new extern ..."
Abstract - Cited by 755 (16 self) - Add to MetaCart
external force for active contours, largely solving both problems. This external force, which we call gradient vector flow (GVF), is computed as a diffusion of the gradient vectors of a gray-level or binary edge map derived from the image. It differs fundamentally from traditional snake external forces

Iterative point matching for registration of free-form curves and surfaces

by Zhengyou Zhang , 1994
"... A heuristic method has been developed for registering two sets of 3-D curves obtained by using an edge-based stereo system, or two dense 3-D maps obtained by using a correlation-based stereo system. Geometric matching in general is a difficult unsolved problem in computer vision. Fortunately, in ma ..."
Abstract - Cited by 660 (8 self) - Add to MetaCart
A heuristic method has been developed for registering two sets of 3-D curves obtained by using an edge-based stereo system, or two dense 3-D maps obtained by using a correlation-based stereo system. Geometric matching in general is a difficult unsolved problem in computer vision. Fortunately

Curvelets: a surprisingly effective nonadaptive representation of objects with edges

by Emmanuel J. Candès, David L. Donoho - IN CURVE AND SURFACE FITTING: SAINT-MALO , 2000
"... It is widely believed that to efficiently represent an otherwise smooth object with discontinuities along edges, one must use an adaptive representation that in some sense ‘tracks ’ the shape of the discontinuity set. This folk-belief — some would say folk-theorem — is incorrect. At the very least ..."
Abstract - Cited by 395 (21 self) - Add to MetaCart
It is widely believed that to efficiently represent an otherwise smooth object with discontinuities along edges, one must use an adaptive representation that in some sense ‘tracks ’ the shape of the discontinuity set. This folk-belief — some would say folk-theorem — is incorrect. At the very

The curvelet transform for image denoising

by Jean-Luc Starck, Emmanuel J. Candes, David L. Donoho - IEEE TRANS. IMAGE PROCESS , 2002
"... We describe approximate digital implementations of two new mathematical transforms, namely, the ridgelet transform [2] and the curvelet transform [6], [5]. Our implementations offer exact reconstruction, stability against perturbations, ease of implementation, and low computational complexity. A cen ..."
Abstract - Cited by 404 (40 self) - Add to MetaCart
, simple thresholding of the curvelet coefficients is very competitive with “state of the art ” techniques based on wavelets, including thresholding of decimated or undecimated wavelet transforms and also including tree-based Bayesian posterior mean methods. Moreover, the curvelet reconstructions exhibit

A generalized Gaussian image model for edge-preserving MAP estimation

by Charles Bouman, Ken Sauer - IEEE Trans. on Image Processing , 1993
"... Absfrucf- We present a Markov random field model which allows realistic edge modeling while providing stable maximum a posteriori MAP solutions. The proposed model, which we refer to as a generalized Gaussian Markov random field (GGMRF), is named for its similarity to the generalized Gaussian distri ..."
Abstract - Cited by 301 (37 self) - Add to MetaCart
Absfrucf- We present a Markov random field model which allows realistic edge modeling while providing stable maximum a posteriori MAP solutions. The proposed model, which we refer to as a generalized Gaussian Markov random field (GGMRF), is named for its similarity to the generalized Gaussian

Face Recognition: the Problem of Compensating for Changes in Illumination Direction

by Yael Adini, Yael Moses, Shimon Ullman - IEEE Transactions on Pattern Analysis and Machine Intelligence , 1997
"... A face recognition system must recognize a face from a novel image despite the variations between images of the same face. A common approach to overcoming image variations because of changes in the illumination conditions is to use image representations that are relatively insensitive to these varia ..."
Abstract - Cited by 353 (3 self) - Add to MetaCart
to these variations. Examples of such representations are edge maps, image intensity derivatives, and images convolved with 2D Gabor-like filters. Here we present an empirical study that evaluates the sensitivity of these representations to changes in illumination, as well as viewpoint and facial expression. Our

On the Removal of Shadows from Images

by Graham D. Finlayson, Steven D. Hordley, Cheng Lu, Mark S. Drew , 2006
"... This paper is concerned with the derivation of a progression of shadow-free image representations. First, we show that adopting certain assumptions about lights and cameras leads to a 1D, gray-scale image representation which is illuminant invariant at each image pixel. We show that as a consequenc ..."
Abstract - Cited by 236 (18 self) - Add to MetaCart
this thresholded edge map, thus deriving the sought-after 3D shadow-free image.

Example-based super-resolution

by William T. Freeman, Thouis R. Jones, Egon C. Pasztor - IEEE COMPUT. GRAPH. APPL , 2001
"... The Problem: Pixel representations for images do not have resolution independence. When we zoom into a bitmapped image, we get a blurred image. Figure 1 shows the problem for a teapot image, rich with real-world detail. We know the teapot’s features should remain sharp as we zoom in on them, yet sta ..."
Abstract - Cited by 349 (5 self) - Add to MetaCart
standard pixel interpolation methods, such as pixel replication (b, c) and cubic spline interpolation (d, e), introduce artifacts or blurring of edges. For images zoomed 3 octaves, such as these, sharpening the interpolated result has little useful effect (f, g). Many applications in graphics or image
Results 1 - 10 of 9,016