Results 1 - 10 of 7,398

Histograms of Oriented Gradients for Human Detection

by Navneet Dalal, Bill Triggs - In CVPR , 2005
"... We study the question of feature sets for robust visual object recognition, adopting linear SVM based human detection as a test case. After reviewing existing edge and gradient based descriptors, we show experimentally that grids of Histograms of Oriented Gradient (HOG) descriptors significantly out ..."
Abstract - Cited by 3735 (9 self) - Add to MetaCart
outperform existing feature sets for human detection. We study the influence of each stage of the computation on performance, concluding that fine-scale gradients, fine orientation binning, relatively coarse spatial binning, and high-quality local contrast normalization in overlapping descriptor blocks

Spatio-temporal energy models for the Perception of Motion

by Edward H. Adelson, James R. Bergen - J. OPT. SOC. AM. A , 1985
"... A motion sequence may be represented as a single pattern in x-y-t space; a velocity of motion corresponds to a three-dimensional orientation in this space. Motion sinformation can be extracted by a system that responds to the oriented spatiotemporal energy. We discuss a class of models for human mot ..."
Abstract - Cited by 904 (9 self) - Add to MetaCart
motion mechanisms in which the first stage consists of linear filters that are oriented in space-time and tuned in spatial frequency. The outputs of quadrature pairs of such filters are squared and summed to give a measure of motion energy. These responses are then fed into an opponent stage. Energy

Relations between the statistics of natural images and the response properties of cortical cells

by David J. Field - J. Opt. Soc. Am. A , 1987
"... The relative efficiency of any particular image-coding scheme should be defined only in relation to the class of images that the code is likely to encounter. To understand the representation of images by the mammalian visual system, it might therefore be useful to consider the statistics of images f ..."
Abstract - Cited by 831 (18 self) - Add to MetaCart
of space, spatial frequency, and orientation (Gabor-like transforms). For many classes of image, such codes will not be an efficient means of representing information. However, the results obtained with six natural images suggest that the orientation and the spatial-frequency tuning of mammalian simple

Shiftable Multi-scale Transforms

by Eero Simoncelli, William T. Freeman, Edward H. Adelson, David J. Heeger , 1992
"... Orthogonal wavelet transforms have recently become a popular representation for multiscale signal and image analysis. One of the major drawbacks of these representations is their lack of translation invariance: the content of wavelet subbands is unstable under translations of the input signal. Wavel ..."
Abstract - Cited by 562 (36 self) - Add to MetaCart
. Wavelet transforms are also unstable with respect to dilations of the input signal, and in two dimensions, rotations of the input signal. We formalize these problems by defining a type of translation invariance that we call "shiftability". In the spatial domain, shiftability corresponds to a

Attention and the detection of signals

by Michael I. Posner, Charles R. R. Snyder, Brian J. Davidson - Journal of Experimental Psychology: General , 1980
"... Detection of a visual signal requires information to reach a system capable of eliciting arbitrary responses required by the experimenter. Detection latencies are reduced when subjects receive a cue that indicates where in the visual field the signal will occur. This shift in efficiency appears to b ..."
Abstract - Cited by 565 (2 self) - Add to MetaCart
to be due to an alignment (orient-ing) of the central attentional system with the pathways to be activated by the visual input. It would also be possible to describe these results as being due to a reduced criterion at the expected target position. However, this description ignores impor-tant constraints

A theory for multiresolution signal decomposition : the wavelet representation

by G. Mallat - IEEE Transaction on Pattern Analysis and Machine Intelligence , 1989
"... Abstract-Multiresolution representations are very effective for analyzing the information content of images. We study the properties of the operator which approximates a signal at a given resolution. We show that the difference of information between the approximation of a signal at the resolutions ..."
Abstract - Cited by 3538 (12 self) - Add to MetaCart
multiresolution representation called a wavelet representation. It is computed with a pyramidal algorithm based on convolutions with quadrature mirror lilters. For images, the wavelet representation differentiates several spatial orientations. We study the application of this representation to data compression

Sparse coding with an overcomplete basis set: a strategy employed by V1

by Bruno A. Olshausen, David J. Fieldt - Vision Research , 1997
"... The spatial receptive fields of simple cells in mammalian striate cortex have been reasonably well described physiologically and can be characterized as being localized, oriented, and ban@ass, comparable with the basis functions of wavelet transforms. Previously, we have shown that these receptive f ..."
Abstract - Cited by 958 (9 self) - Add to MetaCart
The spatial receptive fields of simple cells in mammalian striate cortex have been reasonably well described physiologically and can be characterized as being localized, oriented, and ban@ass, comparable with the basis functions of wavelet transforms. Previously, we have shown that these receptive

Understanding Line Drawings of Scenes with Shadows

by David Waltz - The Psychology of Computer Vision , 1975
"... this paper, how can we recognize the identity of Figs. 2.1 and 2.2? Do we use' learning and knowledge to interpret what we see, or do we somehow automatically see the world as stable and independent bf lighting? What portions of scenes can we understand from local features alone, and what confi ..."
Abstract - Cited by 436 (0 self) - Add to MetaCart
shadow lines and regions, groups regions which belong to the same object, and notices such relations as contact or lack of contact between the objects, support and in-front-of/behind relations between the objects as well as information about the spatial orientation of various regions, all using

A Parametric Texture Model based on Joint Statistics of Complex Wavelet Coefficients

by Javier Portilla, Eero P. Simoncelli - INTERNATIONAL JOURNAL OF COMPUTER VISION , 2000
"... We present a universal statistical model for texture images in the context of an overcomplete complex wavelet transform. The model is parameterized by a set of statistics computed on pairs of coefficients corresponding to basis functions at adjacent spatial locations, orientations, and scales. We de ..."
Abstract - Cited by 424 (13 self) - Add to MetaCart
We present a universal statistical model for texture images in the context of an overcomplete complex wavelet transform. The model is parameterized by a set of statistics computed on pairs of coefficients corresponding to basis functions at adjacent spatial locations, orientations, and scales. We

Poisson Surface Reconstruction

by Michael Kazhdan, Matthew Bolitho, Hugues Hoppe , 2006
"... We show that surface reconstruction from oriented points can be cast as a spatial Poisson problem. This Poisson formulation considers all the points at once, without resorting to heuristic spatial partitioning or blending, and is therefore highly resilient to data noise. Unlike radial basis function ..."
Abstract - Cited by 369 (5 self) - Add to MetaCart
We show that surface reconstruction from oriented points can be cast as a spatial Poisson problem. This Poisson formulation considers all the points at once, without resorting to heuristic spatial partitioning or blending, and is therefore highly resilient to data noise. Unlike radial basis
Results 1 - 10 of 7,398