Jump to Content

Increase text size Decrease text size

SPIE DL Tab

Proceedings Tab

Journals Tab

JEI Tab

EBooks Tab

My Subscription | My Email Alerts | My Article Collections

GENERAL INFORMATION

BROWSE VOLUMES

Year Range:

2012

Volume 21

partial Issue 2 | April - June 2012 | 02xxxx

Issue 1 | January - March 2012 | 01xxxx

2011

Volume 20

2010

Volume 19

2009

Volume 18

2008

Volume 17

2007

Volume 16

2006

Volume 15

2005

Volume 14

2004

Volume 13

2003

Volume 12

2002

Volume 11

2001

Volume 10

2000

Volume 9

1999

Volume 8

1998

Volume 7

1997

Volume 6

1996

Volume 5

1995

Volume 4

1994

Volume 3

1993

Volume 2

1992

Volume 1

Search Issue | RSS Feeds

RSS
Previous Issue

April - June 2012

Volume 21, Issue 2 (partial)

SECTION LISTING

Add

Add Items to Cart

View

View Items in Cart

SELECTED: Export Citations | Show Only | Show All | Show/HideHide Summaries | Add to MyArticles | Email

back to top

Special Section on Quality Control by Artificial Vision

Select this Article		Unsupervised segmentation based on Von Mises circular distributions for orientation estimation in textured images Jean-Pierre Da Costa, Frédéric Galland, Antoine Roueff, and Christian Germain J. Electron. Imaging 21, 021102 (May 07, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.021102 Online Publication Date: May 07, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract In the case of textured images and more particularly of directional textures, a new parametric technique is proposed to estimate the orientation field of textures. It consists of segmenting the image into regions with homogeneous orientations, and estimating the orientation inside each of these regions. This allows us to maximize the size of the samples used to estimate the orientation without being corrupted by the presence of boundaries between regions. For that purpose, the local—hence noisy—orientations of the texture are first estimated using small filters (3×3 pixels). The segmentation of the obtained orientation field image then relies on a generalization of a minimum description length based segmentation technique, to the case of π-periodic circular data modeled with Von Mises probability density functions. This leads to a fast segmentation algorithm without tuning parameters in the optimized criterion. The accuracy of the orientations estimated with the proposed method is then compared with other approaches on synthetic images and an application to the processing of real images is finally addressed.

Select this Article		Original method to compute epipoles using variable homography: application to measure emergent fibers on textile fabrics Jun Xu, Christophe Cudel, Sophie Kohler, Stéphane Fontaine, Olivier Haeberlé, and Marie-Louise Klotz J. Electron. Imaging 21, 021103 (May 07, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.021103 Online Publication Date: May 07, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract Fabric’s smoothness is a key factor in determining the quality of finished textile products and has great influence on the functionality of industrial textiles and high-end textile products. With popularization of the zero defect industrial concept, identifying and measuring defective material in the early stage of production is of great interest to the industry. In the current market, many systems are able to achieve automatic monitoring and control of fabric, paper, and nonwoven material during the entire production process, however online measurement of hairiness is still an open topic and highly desirable for industrial applications. We propose a computer vision approach to compute epipole by using variable homography, which can be used to measure emergent fiber length on textile fabrics. The main challenges addressed in this paper are the application of variable homography on textile monitoring and measurement, as well as the accuracy of the estimated calculation. We propose that a fibrous structure can be considered as a two-layer structure, and then we show how variable homography combined with epipolar geometry can estimate the length of the fiber defects. Simulations are carried out to show the effectiveness of this method. The true length of selected fibers is measured precisely using a digital optical microscope, and then the same fibers are tested by our method. Our experimental results suggest that smoothness monitored by variable homography is an accurate and robust method of quality control for important industrial fabrics.

Select this Article		Multisensor comparison and data fusion for mapping enclosed spaces Shiyu Song, Mohammed Billoo, Clark Guest, and Kamran Mahbobi J. Electron. Imaging 21, 021104 (May 10, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.021104 Online Publication Date: May 10, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract The ability to determine the size and shape of a room or other interior space prior to the entry of personnel can identify risks, aid in planning, and promote efficient allocation of resources. The performance of infrared sensors, acoustic sensors, frequency modulated continuous wave radar, and stereo cameras for mapping an enclosed space is evaluated. A multisensor system and a communication network are demonstrated to map accurately the interior of a building and generate a consistent solution and robust results. The average error of the system is 10 to 30 cm. Processing time for the data fusion algorithm is typically 5 to 20 sec/room to generate the floor plan for the building. Two practical examples are presented. Current limitations of the technology are discussed, and approaches to abate them are proposed.

Select this Article		Review and comparison of non-conventional imaging systems for three-dimensional digitization of transparent objects Fabrice Mériaudeau, Rindra Rantoson, David Fofi, and Christophe Stolz J. Electron. Imaging 21, 021105 (May 07, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.021105 Online Publication Date: May 07, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract Fashion and design greatly influence the conception of manufactured products which now exhibit complex forms and shapes. Two-dimensional quality control procedures (e.g., shape, textures, colors, and 2D geometry) are progressively being replaced by 3D inspection methods (e.g., 3D geometry, colors, and texture on the 3D shape) therefore requiring a digitization of the object surface. Three dimensional surface acquisition is a topic which has been studied to a large extent, and a significant number of techniques for acquiring 3D shapes has been proposed, leading to a wide range of commercial solutions available on the market. These systems cover a wide range from micro-scale objects such as shape from focus and shape from defocus techniques, to several meter sized objects (time of flight technique). Nevertheless, the use of such systems still encounters difficulties when dealing with non-diffuse (non Lambertian) surfaces as is the case for transparent, semi-transparent, or highly reflective materials (e.g., glass, crystals, plastics, and shiny metals). We review and compare various systems and approaches which were recently developed for 3D digitization of transparent objects.

Select this Article		Automatic grading of appearance retention of carpets using intensity and range images Sergio Alejandro Orjuela Vargas, Benhur Ortiz-Jaramillo, Ewout Vansteenkiste, Filip Rooms, Simon De Meulemeester, Robain de Keyser, Lieva Van Langenhove, and Wilfried Philips J. Electron. Imaging 21, 021106 (May 14, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.021106 Online Publication Date: May 14, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract Textiles are mainly used for decoration and protection. In both cases, their original appearance and its retention are important factors for customers. Therefore, evaluation of appearance parameters are critical for quality assurance purposes, during and after manufacturing, to determine the lifetime and/or beauty of textile products. In particular, appearance retention of textile products is commonly certified with grades, which are currently assigned by human experts. However, manufacturers would prefer a more objective system. We present an objective system for grading appearance retention, particularly, for textile floor coverings. Changes in appearance are quantified by using linear regression models on texture features extracted from intensity and range images. Range images are obtained by our own laser scanner, reconstructing the carpet surface using two methods that have been previously presented. We extract texture features using a variant of the local binary pattern technique based on detecting those patterns whose frequencies are related to the appearance retention grades. We test models for eight types of carpets. Results show that the proposed approach describes the degree of wear with a precision within the range allowed to human inspectors by international standards. The methodology followed in this experiment has been designed to be general for evaluating global deviation of texture in other types of textiles, as well as other surface materials.

Select this Article		Single-shot surface profiling by multiwavelength interferometry without carrier fringe introduction Katsuichi Kitagawa J. Electron. Imaging 21, 021107 (May 10, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.021107 Online Publication Date: May 10, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract As a single-shot interferometric technique, spatial carrier interferometry has been thoroughly investigated, and it has been shown to have some problems, such as low spatial resolution. To overcome the problems, we propose a novel single-shot surface profiling technique that does not require carrier introduction. It is based on a model-fitting algorithm and estimates the model parameters and the heights of plural points simultaneously based on their multiwavelength intensity data. The validity of the proposed method is demonstrated by computer simulations and actual experiments.

Select this Article		Fusion of geometric and thermographic data for automated defect detection Beata Oswald-Tranta and Paul O’Leary J. Electron. Imaging 21, 021108 (May 07, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.021108 Online Publication Date: May 07, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract Many workpieces produced in large numbers with a large variety of sizes and geometries, e.g. castings and forgings, have to be 100% inspected. In addition to geometric tolerances, material defects, e.g. surface cracks, also have to be detected. We present a fully automated nondestructive testing technique for both types of defects. The workpiece is subject to continuous motion, and during this motion two measurements are performed. In the first step, after applying a short inductive heating, a thermographic measurement is carried out. An infrared camera records the surface temperature of the workpiece enabling the localization of material defects and surface cracks. In the second step, a light sectioning measurement is performed to measure the three-dimensional geometry of the piece. With the help of feature-based registration the data from the two different sources are fused and evaluated together. The advantage of this technique is that a more reliable decision can be made about the nature of the failures and their possible causes. The same registration technique also can be used for the comparison of different pieces and therefore to localize different failure types, via comparison with a “golden,” defect-free piece. The registration technique can be applied to any part that has unique geometric features, around which moments can be computed. Consequently, the inspection technique can be applied to many different parts. The efficacy of the method is demonstrated with measurements on three parts having different geometries.

Select this Article		Robust algorithm for automated microindentation measurement in Vickers hardness testing Michael Gadermayr, Andreas Maier, and Andreas Uhl J. Electron. Imaging 21, 021109 (May 21, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.021109 Online Publication Date: May 21, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract Current algorithms for automated processing of Vickers hardness testing images are unsuitable for a broad range of images that are taken in industrial environments because such images show great variations in the Vickers indentation as well as in the specimen surface. The authors present a three-stage multiresolution template matching algorithm that shows excellent results, even for such challenging images. The capabilities of this algorithm are compared to known algorithms from the literature and results are presented. The comparison is conducted on two significant indentation image databases with 150 and 216 highly varying images. The applicability of the proposed algorithm is further illustrated by its competitive runtime performance.

Select this Article		Extracting the ridge set as a graph for actin filament length estimation from confocal laser scanning microscopic images Harald Birkholz J. Electron. Imaging 21, 021110 (May 09, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.021110 Online Publication Date: May 09, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract The progress in image acquisition techniques provides life sciences with an abundance of data. Image analysis facilitates the assessment. The actin cytoskeleton plays a crucial role in understanding the behavior of osteoblastic cells on biomaterials. In the flat basal part of the cells, it can be visualized by confocal laser scanning microscopy. In the microscopic images, the stained cytoskeleton appears as a dense network of bright ridges which is so far only qualitatively assessed. For its quantification, there is a need for ridge detection techniques that provide a geometrical description of this graph feature. The state of the art methods do not cope with the systematical degradation by noise, unspecific luminance, and uneven dye uptake. This work presents the key part of a ridge-tracking technique, which makes more efficient use of context information, and evaluate it by its length measurement accuracy. Two random models illustrate the performance against ground truth. Representative microscopic images confirm the applicability.

Select this Article		Automatic classification of three-dimensional segmented computed tomography data using data fusion and support vector machine Ahmad Osman, Valérie Kaftandjian, and Ulf Hassler J. Electron. Imaging 21, 021111 (May 07, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.021111 Online Publication Date: May 07, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract The three dimensional (3D) X-ray computed tomography (3D-CT) has proven its successful application as an inspection method in nondestructive testing. The generated 3D volume uses high efficiency reconstruction algorithms containing all required information on the inner structures of the inspected part. Segmentation of this volume reveals suspicious regions that need to be classified as defective or false alarms. This paper deals with the classification step using data fusion theory, which was successfully applied on 2D X-ray data in previous work along with a support vector machine (SVM). For this study we chose a 3D-CT dataset of aluminium castings that needs to be fully inspected via X-ray CT to ensure their quality. We achieved a true classification rate of 97% on a validation dataset, which proves the effectiveness of the data fusion theory as a method to build a better classifier. Comparison with SVMs shows the importance of selecting the most pertinent features to improve the classifier performance and attaining 98% of true classification rate.

Select this Article		Multiscale image fusion using an adaptive similarity-based sensor weighting scheme and human visual system-inspired contrast measure Shahan C. Nercessian, Karen A. Panetta, and Sos S. Agaian J. Electron. Imaging 21, 021112 (May 10, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.021112 Online Publication Date: May 10, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract The goal of image fusion is to combine multiple source images obtained using different capture techniques into a single image to provide an effective contextual enhancement of a scene for human or machine perception. In practice, considerable value can be gained in the fusion of images that are dissimilar or complementary in nature. However, in such cases, global weighting schemes may not sufficiently weigh the contribution of the pertinent information of the source images, while existing adaptive schemes calculate weights based on the relative amounts of salient features, which can cause severe artifacting or inadequate local luminance in the fusion result. Accordingly, a new multiscale image fusion algorithm is proposed. The approximation coefficient fusion rule of the algorithm is based on a novel similarity based weighting scheme capable of providing improved fusion results when the input source images are either similar or dissimilar to each other. Moreover, the algorithm employs a new detail coefficient fusion rule integrating a parametric multiscale contrast measure. The parametric nature of the contrast measure allows the degree to which psychophysical laws of human vision hold to be tuned based on image-dependent characteristics. Experimental results illustrate the superior performance of the proposed algorithm qualitatively and quantitatively.

Select this Article		Secondary radiations in cone-beam computed tomography: simulation study Patricia Wils, Jean Michel Létang, and Jean Pierre Bruandet J. Electron. Imaging 21, 021113 (May 10, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.021113 Online Publication Date: May 10, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract Accurate quantitative reconstruction in kV cone-beam computed tomography (CBCT) is challenged by the presence of secondary radiations (scattering, fluorescence, and bremsstrahlung photons) coming from the object and from the detector itself. The authors present a simulation study of the CBCT imaging chain and its integration into a comprehensive correction algorithm. A layer model of the flat-panel detector is built in a Monte Carlo environment in order to help in localizing and analyzing the secondary radiations. The contribution of these events to the final image is estimated with a convolution model to account for detector secondary radiations combined with a forced-detection scheme to speed-up the Monte Carlo simulation without loss of accuracy. We more specifically assess to what extent a 2D description of the flat-panel detector would be sufficient for the forward model (i.e., the image formation process) of an iterative correction algorithm, both in terms of energy and incidence angle of incoming photons. Results show that both object and detector secondary radiations have to be considered in CBCT. The correction algorithm iteratively compensates for the secondary radiations and the beam hardening in object space. Preliminary results on tomographic acquisitions demonstrate a quantitative improvement on the first iteration.

Select this Article		Efficient focus assessment for a computer vision-based Vickers hardness measurement system Andreas Maier, Georg Niederbrucker, Sebastian Stenger, and Andreas Uhl J. Electron. Imaging 21, 021114 (May 15, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.021114 Online Publication Date: May 15, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract A large variety of computationally lightweight functions used for assessing image sharpness in the spatial domain is evaluated for application in a passive autofocus system in the context of microindentation-based Vickers hardness testing. Alternatively, the file size of compressed JPEG images is proposed to determine image sharpness. The functions are evaluated on a significant dataset of microindentation images with respect to their properties required for focus search and sharpness assessment, their robustness to downsampling the image data, and their computational demand. Experiments suggest that of all spatial domain techniques considered, the simple Brenner autofocus function is the best compromise between accuracy and computational effort, while JPEG file size is a versatile solution when the application context allows.

Select this Article		Quantification of overlapping polygonal-shaped particles based on a new segmentation method of in situ images during crystallization Ola Suleiman Ahmad, Johan Debayle, Nesrine Gherras, Benoît Presles, Gilles Févotte, and Jean-Charles Pinoli J. Electron. Imaging 21, 021115 (May 10, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.021115 Online Publication Date: May 10, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract Quantification of the overlapping particles in crystallization processes is very important for the quality control of chemical products or drugs. We present a method of segmentation of polygonal-shaped (i.e., rectangles, regular/irregular prisms) and overlapping particles from in situ images during a crystallization process for measuring their size distributions. The method is first based on detecting the geometric features of the particles identified by their salient corners. A clustering technique is then applied by grouping three correspondent salient corners belonging to the same particle. The proposed method is applied on particles of ammonium oxalate during batch crystallization in pure water. The particle size distributions are calculated, and a quantitative comparison between the proposed method and a manual sizing is performed. The method showed that it is valid for analyzing the crystal growth, and the results are promising for monitoring the particle size distribution.

Select this Article		Color image enhancement based on the discrete cosine transform coefficient histogram Karen Panetta, Junjun Xia, and Sos Agaian J. Electron. Imaging 21, 021117 (May 10, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.021117 Online Publication Date: May 10, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract This paper presents a new technique for contrast enhancement for color images called histogram shifting with alpha rooting. The novelty in the presented method consists in adapting spatial domain techniques into the transform domain. The benefits of operating in the transform domain include low complexity of computations, ease of viewing, and manipulation of the frequency composition of the image and preservation of the phase information. The combination of the alpha-rooting algorithm, coupled with histogram shifting shows the method’s effectiveness for enhancing overexposed images. The contrast enhancement parameter of the algorithm is established automatically based on the entropy of the images. A comprehensive comparative study on image-enhancement algorithms based on discrete cosine transform coefficients is provided. Computer simulations and analysis are provided to compare the enhancement performance of the proposed technique to state of the art approaches. We perform a statistical analysis on the results and quantitatively show that the proposed approach performs well for color image enhancement, which is also validated by ratings from human observers.

Select this Article		Quantitative evaluation of image registration techniques in the case of retinal images Yann Gavet, Mathieu Fernandes, and Jean-Charles Pinoli J. Electron. Imaging 21, 021118 (May 10, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.021118 Online Publication Date: May 10, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract In human retina observation (with non mydriatic optical microscopes), an image registration process is often employed to enlarge the field of view. Analyzing all the images takes a lot of time. Numerous techniques have been proposed to perform the registration process. Its good evaluation is a difficult question that is then raising. This article presents the use of two quantitative criterions to evaluate and compare some classical feature-based image registration techniques. The images are first segmented and the resulting binary images are then registered. The good quality of the registration process is evaluated with a normalized criterion based on the ϵ dissimilarity criterion, and the figure of merit criterion (fom), for 25 pairs of images with a manual selection of control points. These criterions are normalized by the results of the affine method (considered as the most simple method). Then, for each pair, the influence of the number of points used to perform the registration is evaluated.

back to top

Regular Articles

Select this Article		Color correction with hue-determined compensation for illumination changing Cheung-Wen Chang and Yung-Nien Sun J. Electron. Imaging 21, 023001 (Apr 23, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.023001 Online Publication Date: Apr 23, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract Color correction is important in vision applications. We aim to improve conventional transformation with a linear hypothesis of color correction (i.e., von Kries method) by innovatively using a hue-determined matrix. A new model, named the hue-compensated diagonal model (HCDM), is proposed to benefit correcting colors with chromatic-saturated illuminations. Inspired by the chromatic adaptation occurring in the human visual system (HVS), the HCDM reinforces the illuminant complementary color by weighting the von Kries coefficients. These HCDM weighting terms, being illuminant-hue specific based on the relative absorption model (RAM), consist of the proposed hue-chromatic characteristic function with learning parameters. As a result, the HCDM out-performed both the principle component analysis (PCA) approach and the von Kries method in most synthetic experiments, and achieved better results than the von Kries method in real image experiments. Thus, the proposed HCDM, with global-processing capability and real-image applicability, can be used as an effective model in color reproductions and image applications.

Select this Article OPEN ACCESS		Simple wave-field rendering for photorealistic reconstruction in polygon-based high-definition computer holography Kyoji Matsushima, Hirohito Nishi, and Sumio Nakahara J. Electron. Imaging 21, 023002 (Apr 26, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.023002 Online Publication Date: Apr 26, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract A simple and practical technique is presented for creating fine three-dimensional (3D) images with polygon-based computer-generated holograms. The polygon-based method is a technique for computing the optical wave-field of virtual 3D scenes given by a numerical model. The presented method takes less computation time than common point-source methods and produces fine spatial 3D images of deep 3D scenes that convey a strong sensation of depth, unlike conventional 3D systems providing only binocular disparity. However, smooth surfaces cannot be reconstructed using the presented method because the surfaces are approximated by planar polygons. This problem is resolved by introducing a simple rendering technique that is almost the same as that in common computer graphics, since the polygon-based method has similarity to rendering techniques in computer graphics. Two actual computer holograms are presented to verify and demonstrate the proposed technique. One is a hologram of a live face whose shape is measured using a 3D laser scanner that outputs polygon-mesh data. The other is for a scene including the moon. Both are created employing the proposed rendering techniques of the texture mapping of real photographs and smooth shading.

Select this Article		Virtual camera rectification with geometrical approach on single-lens stereovision using a biprism Kah Bin Lim, Daolei Wang, and Wei Loon Kee J. Electron. Imaging 21, 023003 (May 22, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.023003 Online Publication Date: May 22, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract We propose a geometrical approach for virtual camera rectification on uncalibrated single-lens stereovision using a biprism. This system is also called a virtual stereovision system, as the image captured can be divided into two which are equivalent to two images captured using two cameras with different perspectives. The proposed method is divided into two parts. The first part is to compute the projection transformation matrix of two virtual cameras based on a unique geometrical ray sketching, which can accurately recover the extrinsic parameters, and the second part is to compute the rectification transformation matrix, which is applied on the images captured using the system. As the geometrical analysis eliminates the complex calibration process and rectification reduces the correspondence searching to one-dimensional, this method provides a simple stereo matching technique for this system. Experimental results are presented to show the effectiveness of the approach.

Select this Article OPEN ACCESS		Video denoising using overlapped motion compensation and advanced collaborative filtering Tae Hwan Lee, Jin-Ku Kang, and Byung Cheol Song J. Electron. Imaging 21, 023004 (May 10, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.023004 Online Publication Date: May 10, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract We present spatiotemporal denoising based on overlapped motion compensation and advanced collaborative filtering. First, noise-robust overlapped motion compensation is performed on a block basis for temporal grouping. Next, the K-nearest neighbors of each block are grouped in a 3D array, and the 3D array is transformed. Then, adaptive soft thresholding is performed in the 3D transform domain. In addition, a modified weighting strategy for aggregation is applied for better visual quality. Simulation results show that the proposed algorithm improves the peak signal-to-noise ratio performance by about 2 dB in comparison with the state-of-the-art technique while providing much better subjective visual quality.

Select this Article		Novel adaptive high-performance and nonlinear filtering algorithm for mixed noise removal Xueqing Zhao and Xiaoming Wang J. Electron. Imaging 21, 023005 (May 14, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.023005 Online Publication Date: May 14, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract A novel adaptive high-performance and nonlinear filtering algorithm (AHPNFA) is proposed for the removal of mixed noise from corrupted images. This algorithm contains two stages: noise determining and noise removing. In the first stage, for each filtering window of the processed image, the center pixel and its nearest neighbors are modeled as a statistical variable. By exploiting Chebyshev’s theorem, the fuzzy mean process is used to estimate adaptively the detection parameters that are required in determining whether the current pixel is corrupted or not. In the second stage, the Radon transform is performed to determine the texture direction probability density distributions of local areas of images, then using the texture direction probability density distributions and the local features of the image remove the noisy pixels. To demonstrate the advantages, the proposed AHPNFA is compared with the other test filters both visually and quantitatively. Simulation results show that the proposed AHPNFA has better values in important evaluation metrics; in particular, the computational complexity of the AHPNFA is about five to 11 times lower than the other test filters used in the comparison, therefore, the proposed AHPNFA has better performances.

Select this Article		Fractional-order bidirectional diffusion for image up-sampling Zemin Ren, Chuanjiang He, and Meng Li J. Electron. Imaging 21, 023006 (May 14, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.023006 Online Publication Date: May 14, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract Following the recently proposed total variation (TV) up-sampling method, we present a novel image up-sampling algorithm based on fractional-order bidirectional diffusion. For the bidirectional diffusion, the forward diffusion occurs on the light side of edge, while the backward diffusion proceeds on the dark side. This bidirectional diffusion can reduce the edge width and avoid the appearances of false edge or texture and block effects. Moreover, the fractional-order derivative is used to avoid strong contrast near the edge in the interpolated images. The experiments show that, unlike the TV up-sampling (TVUP) method, the proposed algorithm does not suffer from the drift of edges, block effect in the smooth regions, false edges, and false texture.

Select this Article		Efficient postprocessing of edge maps for image segmentation based on greedy correction cost minimization Robert Cupec, Emmanuel Karlo Nyarko, and Dražen Slišković J. Electron. Imaging 21, 023007 (May 17, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.023007 Online Publication Date: May 17, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract A highly efficient postprocessing technique which enables the result of edge detection to be used for image segmentation is proposed. The method starts from an edge map obtained by a standard edge detection tool, e.g., Canny edge detector, and corrects it to obtain an edge map in which every edge point belongs to a closed boundary of an image region. The correction of the original edge map assumes removing some of the existing edge points as well as inserting virtual edge points. The proposed edge map correction procedure consists of two stages: (1) edge linking, which closes the gaps in edge contours by inserting virtual edge elements, and (2) edge pruning, which rejects spurious contours thereby avoiding over-segmentation. The edge pruning procedure performs an iterative greedy minimization of a correction cost function, while keeping all contours of the edge map closed. The proposed approach is evaluated using a set of standard test images.

Select this Article		Iterative normalization method for improved prostate cancer localization with multispectral magnetic resonance imaging Xin Liu and Imam Samil Yetik J. Electron. Imaging 21, 023008 (May 17, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.023008 Online Publication Date: May 17, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract Use of multispectral magnetic resonance imaging has received a great interest for prostate cancer localization in research and clinical studies. Manual extraction of prostate tumors from multispectral magnetic resonance imaging is inefficient and subjective, while automated segmentation is objective and reproducible. For supervised, automated segmentation approaches, learning is essential to obtain the information from training dataset. However, in this procedure, all patients are assumed to have similar properties for the tumor and normal tissues, and the segmentation performance suffers since the variations across patients are ignored. To conquer this difficulty, we propose a new iterative normalization method based on relative intensity values of tumor and normal tissues to normalize multispectral magnetic resonance images and improve segmentation performance. The idea of relative intensity mimics the manual segmentation performed by human readers, who compare the contrast between regions without knowing the actual intensity values. We compare the segmentation performance of the proposed method with that of z-score normalization followed by support vector machine, local active contours, and fuzzy Markov random field. Our experimental results demonstrate that our method outperforms the three other state-of-the-art algorithms, and was found to have specificity of 0.73, sensitivity of 0.69, and accuracy of 0.79, significantly better than alternative methods.

Select this Article		Fast mode decision algorithm for extended macroblock motion estimation in key technology areas Liquan Shen and Zhaoyang Zhang J. Electron. Imaging 21, 023009 (May 21, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.023009 Online Publication Date: May 21, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract Block sizes larger than the traditional 16×16 macroblock (MB) structure and extended macroblock (EMB) size motion estimation (ME) are introduced in joint model key technology areas software to improve the inter block coding efficiency. Similar to H.264, variable size motion estimation (VS-ME) is still adopted for each 16×16 MB including 16×16, 16×8, 8×16, 8×8, 8×4, 4×8, and 4×4. EMB size ME and VS-ME achieve the highest possible coding efficiency, but result in extremely large coding time which obstructs it from practical use. A fast mode decision algorithm for EMBs based on motion homogeneity is proposed to reduce the computational complexity of ME. The basic idea of the proposed method is to utilize the spatial property of motion field in prediction where EMB size ME and small size ME (including 8×8, 8×4, 4×8 and 4×4) are needed, and only in these regions EMB size ME and small size ME are enabled. The motion field is generated by the corresponding motion vectors in spatial window. Simulation results show that the proposed algorithm can save 55% average computational complexity, with negligible loss of coding efficiency.

Select this Article		Action recognition using spatiotemporal features and hybrid generative/discriminative models Jia Liu and Jie Yang J. Electron. Imaging 21, 023010 (May 22, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.023010 Online Publication Date: May 22, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract We propose a new method for human action recognition based on multiple features and a hybrid generative/discriminative model. Specifically, we propose a new action representation based on computing a rich set of descriptors from Affine-SIFT key point trajectories. A new hybrid generative/discriminative approach based on support vector machine and topic model is proposed using Fisher kernel method for action recognition. Fisher score for the topic model is evaluated by the variational inference algorithm. To obtain efficient and compact representations for actions, we develop a feature fusion method to combine spatial-temporal local motion descriptors and demonstrate how this kernel framework can be used to combine different types of features and models into a single classiﬁer. Our experiments, conducted on a number of popular datasets, show performance improvements over the corresponding generative approach and are competitive with the best results reported in the literature.

Select this Article		Three-dimensional object retrieval based on vector quantization of invariant descriptors Hedi Tabia, Mohamed Daoudi, Olivier Colot, and Jean-Philippe Vandeborre J. Electron. Imaging 21, 023011 (May 21, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.023011 Online Publication Date: May 21, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract A novel method for three-dimensional (3-D) shape retrieval using bag-of-feature techniques (BoF) is proposed. This method is based on vector quantization of invariant descriptors of 3-D object patches. Firstly, it starts by selecting and then describing a set of points from the 3-D object. Such descriptors have the advantage of being invariant to different transformations that a shape can undergo. Based on vector quantization, we cluster those descriptors to form a shape vocabulary. Then, each point selected in the object is associated to a cluster (word) in that vocabulary. Finally, a weighted vector counting the occurrences of every word is computed. These results clearly demonstrate that the method is robust to nonrigid and deformable shapes, in which the class of transformations may be very wide due to the capability of such shapes to bend and assume different forms.

Select this Article		Image processing for three-dimensional scans generated by time-of-flight range cameras Holger Schöner, Frank Bauer, Adrian Dorrington, Bettina Heise, Volkmar Wieser, Andrew Payne, Michael J. Cree, and Bernhard Moser J. Electron. Imaging 21, 023012 (May 21, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.023012 Online Publication Date: May 21, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract Time-of-flight (TOF) full-field range cameras use a correlative imaging technique to generate three-dimensional measurements of the environment. Though reliable and cheap they have the disadvantage of high measurement noise and errors that limit the practical use of these cameras in industrial applications. We show how some of these limitations can be overcome with standard image processing techniques specially adapted to TOF camera data. Additional information in the multimodal images recorded in this setting, and not available in standard image processing settings, can be used to improve reduction of measurement noise. Three extensions of standard techniques, wavelet thresholding, adaptive smoothing on a clustering based image segmentation, and an extended anisotropic diffusion filtering, make use of this information and are compared on synthetic data and on data acquired from two different off-the-shelf TOF cameras. Of these methods, the adapted anisotropic diffusion technique gives best results, and is implementable to perform in real time using current graphics processing unit (GPU) hardware. Like traditional anisotropic diffusion, it requires some parameter adaptation to the scene characteristics, but allows for low visualization delay and improved visualization of moving objects by avoiding long averaging periods when compared to traditional TOF image denoising.

Select this Article		Binary document image compression using a three-symbol grouped code dictionary Hermilo Sánchez-Cruz and Mario A. Rodríguez-Díaz J. Electron. Imaging 21, 023013 (May 21, 2012); http://dx.doi.org/10.1117/1.JEI.21.2.023013 Online Publication Date: May 21, 2012 Full Text: Read Online (HTML) \| Download PDF
	+ -	Show Abstract A novel method of lossy compression for images of text documents is proposed. The method is based on classifying the objects, characters, and pictures that appear in the images. We used the Tanimoto distance to group the objects into different classes to create an object dictionary; then, we codified the instances of each class by means of a code of three symbols called the three orthogonal symbol chain code (3OT). We applied an entropy coder to the resulting chain, which groups the symbols of 3OT; finally, we compressed the chain obtained by using the Paq8l archiver, which is based on a context-mixing algorithm divided into a predictor and an arithmetic coder. We obtained a high performance in memory storage, with an average of 2.17 times better compression levels with respect to the international standard Joint Bi-level Image Experts Group 2 on its lossy information version.

View presentations in solar, OLEDs, and more

Field Guide to Geometrical Optics

Join SPIE