In this paper we introduce a new approach to characterizing image quality: visual equivalence, Images are visually equivalent if they convey the same information about object appearance even if they are visibly differ...
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ISBN:
(纸本)9780892082810
In this paper we introduce a new approach to characterizing image quality: visual equivalence, Images are visually equivalent if they convey the same information about object appearance even if they are visibly different. In a series of psychophysical experiments we explore how object geometry, material, and illumination interact to produce images that are visually equivalent, and we identify how two kinds of transformations on illumination fields (blurring and warping) influence observers' judgments of equivalence. We use the results of the experiments to derive metrics that can serve as visual equivalence predictors (VEPs) and we generalize these metrics so they can be applied to novel objects and scenes. Finally we validate the predictors in a confirmatory study, and show that they reliably predict observer's judgments of equivalence. Visual equivalence is a significant new approach to measuring image quality that goes beyond existing visible difference metrics by leveraging the fact that some kinds of image differences do not matter to human observers. By taking advantage of higher order aspects of visual object coding, visual equivalence metrics should enable the development of powerful new classes of image capture, compression, rendering, and display algorithms.
This paper introduces techniques for the exploration of images augmented with additional information. We present the so-called Meta-Previewer and propose the Cascading-Views which are widgets that can assist the end-u...
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Determining the influence of an object on other objects in a database, based on proximity, is important in many applications. Abstractly, we wish to pre-process a set, P, of points in d-space so that the points of P t...
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ISBN:
(纸本)9781605583235
Determining the influence of an object on other objects in a database, based on proximity, is important in many applications. Abstractly, we wish to pre-process a set, P, of points in d-space so that the points of P that are assigned a new query point q as a Euclidean nearest neighbor can be reported quickly. These are the reverse nearest neighbors of q and are the ones most influenced by q. This generalizes to bichromatic reverse nearest neighbors, in which two sets, clients and servers, are given, where each client is influenced by some server, and of interest are the clients that are assigned a new server q as a nearest neighbor. Both extend to higher orders k > 1, where we seek the points that are assigned q as one of their k nearest neighbors, indicating varying degrees of influence. Each version also has a counterpart where "nearest" is replaced by "farthest", signifying low influence. We present a general approach that solves such reverse proximity query problems in an efficient and unified way, in any dimension, using well-known geometric transformations. We also give simple approximation algorithms in two and three dimensions (the primary domain of GIS applications) that report points that are "close to"being the desired true reverse proximity neighbors, as determined by a user-specified error parameter. This is based on approximating the proximity loci of the points by suitable convex polytopes that are amenable to simple and efficient querying. Theoretical analyses show that our solutions are fast and provably accurate, and this is further confirmed by experiments. Copyright 2008 ACM.
We present an adaptive dynamic load balancing scheme for 3D texture based sort-last parallel volume rendering on a PC cluster equipped with GPUs. Our scheme exploits not only task parallelism but also data parallelism...
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This paper discusses fast and accurate methods to solve total variation (TV) models on the graphics processing unit (GPU). We review two prominent models incorporating TV regularization and present different algorithm...
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This paper discusses fast and accurate methods to solve total variation (TV) models on the graphics processing unit (GPU). We review two prominent models incorporating TV regularization and present different algorithms to solve these models. We mainly concentrate on variational techniques, i.e. algorithms which aim at solving the Euler Lagrange equations associated with the variational model. We then show that particularly these algorithms can be effectively accelerated by implementing them on parallel architectures such as GPUs. For comparison we chose a state-of-the-art method based on discrete optimization techniques. We then present the results of a rigorous performance evaluation including 2D and 3D problems. As a main result we show that the our GPU based algorithms clearly outperform discrete optimization techniques in both speed and maximum problem size.
作者：
Sreekumar, M GVisiting Professor
Faculty of Computer Science and Information Technology University of Malaya Kuala Lumpur Malaysia
The developments in technology during the recent past, especially in ICTs (information and communication technologies), are tremendous, and the magnitude of changes that have been effecting the scholarly communication...
The developments in technology during the recent past, especially in ICTs (information and communication technologies), are tremendous, and the magnitude of changes that have been effecting the scholarly communication is amazing. In reality, scholarly communication system has largely been monopolized by publishers. Publishers obtain copyright from the author while accepting their scripts for publication, and paradoxically, the author or his/her university/institute will not have access to the article unless they have a subscription to the journal. On the other side, the spiralling costs of scholarly journals and the shrinking library budgets are of grave concern to the academic and research fraternity regardless of geographic conditions. The deprived authors/institutions are now trying out OA (Open Access) alternatives for scientific publication and communication with a view to escape the clutches of the publishers. The OA, as it is literally explanatory, intends seamless and free online access to all scholarly works emanating from the scientific fraternity worldwide. OA initiatives are indeed poised to revolutionize the scholarly communication process wherein the copyright of the article will partly rest (non-exclusive) with the authors, which is a departure from the conventional publishing process. This paper highlights the importance and the broad spectrum of benefits the OA movement offers to the academic and research community, especially, by way of policy formulations that would lead to mandating open access to all publications resulting from publicly funded research. It also suggests various models for practising and promoting OA, which could be emulated by these organizations in meeting the growing challenges that they face now in terms of budgetary constraints. It will also help in their earnest efforts towards providing assured access to a (near) comprehensive body of information and knowledge to their own communities.
In general, a duplicated or tampered one of document can be obtained by duplicating machine. How to distinguish watermark quality from the first printing document and the duplicated or tampered one? In this paper we i...
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In general, a duplicated or tampered one of document can be obtained by duplicating machine. How to distinguish watermark quality from the first printing document and the duplicated or tampered one? In this paper we introduce a document watermarking arithmetic which is robust to copying. The arithmetic is based on the FMT transformation. The document is regarded as one image and is embedded 8 digitals. Experiments results show that the scheme can resist first printing and scan process. Furthermore watermark cannot be extracted from the duplicated or tampered one.
This paper introduces a network architecture called Vehicular Wireless Burst Switching (VWBS). The main objective of this architecture is to provide low-cost connectivity solution for isolated and dispersed regions wi...
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Lane detection is an essential component of autonomous mobile robot applications. Any lane detection method has to deal with the varying conditions of the lane and surrounding that the robot would encounter while movi...
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Lane detection is an essential component of autonomous mobile robot applications. Any lane detection method has to deal with the varying conditions of the lane and surrounding that the robot would encounter while moving. Lane detection procedure can provide estimates for the position and orientation of the robot within the lane and also can provide a reference system for locating other obstacles in the path of the robot. In this paper we present a method for lane detection in video frames of a camera mounted on top of the mobile robot. Given video input from the camera, the gradient of the current lane in the near field of view are automatically detected. Randomized Hough Transform is used for extracting parametric curves from the images acquired. A priori knowledge of the lane position is assumed for better accuracy of lane detection.
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