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Proceedings Article

Image Processing

01 Jan 1994-
TL;DR: The main focus in MUCKE is on cleaning large scale Web image corpora and on proposing image representations which are closer to the human interpretation of images.
Abstract: MUCKE aims to mine a large volume of images, to structure them conceptually and to use this conceptual structuring in order to improve large-scale image retrieval. The last decade witnessed important progress concerning low-level image representations. However, there are a number problems which need to be solved in order to unleash the full potential of image mining in applications. The central problem with low-level representations is the mismatch between them and the human interpretation of image content. This problem can be instantiated, for instance, by the incapability of existing descriptors to capture spatial relationships between the concepts represented or by their incapability to convey an explanation of why two images are similar in a content-based image retrieval framework. We start by assessing existing local descriptors for image classification and by proposing to use co-occurrence matrices to better capture spatial relationships in images. The main focus in MUCKE is on cleaning large scale Web image corpora and on proposing image representations which are closer to the human interpretation of images. Consequently, we introduce methods which tackle these two problems and compare results to state of the art methods. Note: some aspects of this deliverable are withheld at this time as they are pending review. Please contact the authors for a preview.
Citations
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Book
03 Oct 1988
TL;DR: This chapter discusses two Dimensional Systems and Mathematical Preliminaries and their applications in Image Analysis and Computer Vision, as well as image reconstruction from Projections and image enhancement.
Abstract: Introduction. 1. Two Dimensional Systems and Mathematical Preliminaries. 2. Image Perception. 3. Image Sampling and Quantization. 4. Image Transforms. 5. Image Representation by Stochastic Models. 6. Image Enhancement. 7. Image Filtering and Restoration. 8. Image Analysis and Computer Vision. 9. Image Reconstruction From Projections. 10. Image Data Compression.

8,504 citations

Journal ArticleDOI
TL;DR: The image coding results, calculated from actual file sizes and images reconstructed by the decoding algorithm, are either comparable to or surpass previous results obtained through much more sophisticated and computationally complex methods.
Abstract: Embedded zerotree wavelet (EZW) coding, introduced by Shapiro (see IEEE Trans. Signal Processing, vol.41, no.12, p.3445, 1993), is a very effective and computationally simple technique for image compression. We offer an alternative explanation of the principles of its operation, so that the reasons for its excellent performance can be better understood. These principles are partial ordering by magnitude with a set partitioning sorting algorithm, ordered bit plane transmission, and exploitation of self-similarity across different scales of an image wavelet transform. Moreover, we present a new and different implementation based on set partitioning in hierarchical trees (SPIHT), which provides even better performance than our previously reported extension of EZW that surpassed the performance of the original EZW. The image coding results, calculated from actual file sizes and images reconstructed by the decoding algorithm, are either comparable to or surpass previous results obtained through much more sophisticated and computationally complex methods. In addition, the new coding and decoding procedures are extremely fast, and they can be made even faster, with only small loss in performance, by omitting entropy coding of the bit stream by the arithmetic code.

5,890 citations

Journal ArticleDOI
TL;DR: Eight constructs decellularized hearts by coronary perfusion with detergents, preserved the underlying extracellular matrix, and produced an acellular, perfusable vascular architecture, competent a cellular valves and intact chamber geometry that could generate pump function in a modified working heart preparation.
Abstract: About 3,000 individuals in the United States are awaiting a donor heart; worldwide, 22 million individuals are living with heart failure. A bioartificial heart is a theoretical alternative to transplantation or mechanical left ventricular support. Generating a bioartificial heart requires engineering of cardiac architecture, appropriate cellular constituents and pump function. We decellularized hearts by coronary perfusion with detergents, preserved the underlying extracellular matrix, and produced an acellular, perfusable vascular architecture, competent acellular valves and intact chamber geometry. To mimic cardiac cell composition, we reseeded these constructs with cardiac or endothelial cells. To establish function, we maintained eight constructs for up to 28 d by coronary perfusion in a bioreactor that simulated cardiac physiology. By day 4, we observed macroscopic contractions. By day 8, under physiological load and electrical stimulation, constructs could generate pump function (equivalent to about 2% of adult or 25% of 16-week fetal heart function) in a modified working heart preparation.

2,454 citations

Journal ArticleDOI
01 Sep 1997
TL;DR: This paper examines automated iris recognition as a biometrically based technology for personal identification and verification from the observation that the human iris provides a particularly interesting structure on which to base a technology for noninvasive biometric assessment.
Abstract: This paper examines automated iris recognition as a biometrically based technology for personal identification and verification. The motivation for this endeavor stems from the observation that the human iris provides a particularly interesting structure on which to base a technology for noninvasive biometric assessment. In particular the biomedical literature suggests that irises are as distinct as fingerprints or patterns of retinal blood vessels. Further, since the iris is an overt body, its appearance is amenable to remote examination with the aid of a machine vision system. The body of this paper details issues in the design and operation of such systems. For the sake of illustration, extant systems are described in some amount of detail.

2,046 citations


Cites methods from "Image Processing"

  • ...system makes us of an isotropic bandpass decomposition derived from application of Laplacian of Gaussian filters [25], [29] to the image data....

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  • ...In practice, the filtered image is realized as a Laplacian pyramid [8], [29]....

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Journal ArticleDOI
TL;DR: This paper identifies some promising techniques for image retrieval according to standard principles and examines implementation procedures for each technique and discusses its advantages and disadvantages.

1,910 citations


Cites background or methods from "Image Processing"

  • ...Structural description of chromosome shape (reprinted from [14])....

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  • ...Common invariants include (i) geometric invariants such as cross-ratio, length ratio, distance ratio, angle, area [69], triangle [70], invariants from coplanar points [14]; (ii) algebraic invariants such as determinant, eigenvalues [71], trace [14]; (iii) di<erential invariants such as curvature, torsion and Gaussian curvature....

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  • ...Designers of shape invariants argue that although most of other shape representation techniques are invariant under similarity transformations (rotation, translation and scaling), they depend on viewpoint [14]....

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  • ...The extracting of the convex hull can use both boundary tracing method [14] and morphological methods [11,15]....

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  • ...Assuming the shape boundary has been represented as a shape signature z(i), the rth moment mr and central moment r can be estimated as [14]...

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References
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Journal ArticleDOI
TL;DR: An unsupervised, automatic tracking and segmentation framework for high‐throughput microscopy image sequences, tying together two fundamental aspects of cell lineage construction, namely cell segmentation and tracking, via a Bayesian inference of dynamic models.

41 citations

Journal ArticleDOI
TL;DR: It is shown using uniform methodology at the whole-animal level that intact, unanesthetized pigeons had significantly higher absorption of l-arabinose and l-rhamnose, two water-soluble compounds used to measure paracellular absorption, than similarly sized laboratory rats.
Abstract: Increasing evidence indicates that small birds have more extensive non-mediated, paracellular intestinal absorption of hydrosoluble compounds than do mammals, although studies have not employed uniform methodologies or demonstrated differences at the tissue level. The mechanistic bases behind apparent species differences are poorly understood. We show using uniform methodology at the whole-animal level that intact, unanesthetized pigeons had significantly higher absorption of l-arabinose and l-rhamnose, two water-soluble compounds used to measure paracellular absorption, than similarly sized laboratory rats. The species differences were also evident using perfused isolated loops of duodenum, showing that the difference in paracellular absorption occurred at the tissue level, even when d-glucose absorption rates (transcellular+paracellular) were similar between the two species. The greater absorption of these probes in pigeons could not be explained by mediated uptake of the putative paracellular probes, or by increased nominal surface area, increased villus area or increased number of tight junctions. Rats and pigeons had comparable absorption of larger probes, which is consistent with similar effective pore size of the tight junction between enterocytes. The elimination of these mechanistic explanations might suggest that pigeon intestine has relatively higher paracellular solvent drag, but pigeon duodenal segments did not have higher net water absorption than rat duodenal segments. Whatever the exact mechanism(s), the paracellular pathway of both species limits substantial (>5%) fractional absorption to molecules smaller than about 4.8 A ( M r ca. 350), and permeability to smaller molecules at the tissue level is higher in pigeons than in rats.

41 citations

Journal ArticleDOI
TL;DR: A BUS despeckling method based on anisotropic diffusion guided by Log-Gabor filters (ADLG) is proposed, which suggests that ADLG outperforms the four speckle removal filters compared with respect to simulated and real BUS images.
Abstract: Breast ultrasound (BUS) is considered the most important adjunct method to mammography for diagnosing cancer. However, this image modality suffers from an intrinsic artifact called speckle noise, which degrades spatial and contrast resolution and obscures the screened anatomy. Hence, it is necessary to reduce speckle artifacts before performing image analysis by means of computer-aided diagnosis systems, for example. In addition, the trade-off between smoothing level and preservation of lesion contour details should be addressed by speckle reduction schemes. In this scenario, we propose a BUS despeckling method based on anisotropic diffusion guided by Log-Gabor filters (ADLG). Because we assume that different breast tissues have distinct textures, in our approach we perform a multichannel decomposition of the BUS image using Log-Gabor filters. Next, the conduction coefficient of anisotropic diffusion filtering is computed using texture responses instead of intensity values as stated originally. The proposed algorithm is validated using both synthetic and real breast data sets, with 900 and 50 images, respectively. The performance measures are compared with four existing speckle reduction schemes based on anisotropic diffusion: conventional anisotropic diffusion filtering (CADF), speckle-reducing anisotropic diffusion (SRAD), texture-oriented anisotropic diffusion (TOAD), and interference-based speckle filtering followed by anisotropic diffusion (ISFAD). The validity metrics are the Pratt's figure of merit, for synthetic images, and the mean radial distance (in pixels), for real sonographies. Figure of merit and mean radial distance indices should tend toward '1' and '0', respectively, to indicate adequate edge preservation. The results suggest that ADLG outperforms the four speckle removal filters compared with respect to simulated and real BUS images. For each method--ADLG, CADF, SRAD, TOAD and ISFAD--the figure of merit median values are 0.83, 0.40, 0.39, 0.51 and 0.59, and the mean radial distance median results are 4.19, 6.29, 6.39, 6.43 and 5.88.

41 citations

Journal ArticleDOI
TL;DR: Results highlighted a different ecological status of H. stipulacea at the edges of the gradient, where plants showed not only marked differences in morphology and biochemistry, but also the most distinct associated bacterial consortium.
Abstract: Halophila stipulacea is a small tropical seagrass species. It is the dominant seagrass species in the Gulf of Aqaba (GoA; northern Red Sea), where it grows in both shallow and deep environments (1-50 m depth). Native to the Red Sea, Persian Gulf, and Indian Ocean, this species has invaded the Mediterranean and has recently established itself in the Caribbean Sea. Due to its invasive nature, there is growing interest to understand this species' capacity to adapt to new conditions, which might be attributed to its ability to thrive in a broad range of ecological niches. In this study, a multidisciplinary approach was used to depict variations in morphology, biochemistry (pigment and phenol content) and epiphytic bacterial communities along a depth gradient (4-28 m) in the GoA. Along this gradient, H. stipulacea increased leaf area and pigment contents (Chlorophyll a and b, total Carotenoids), while total phenol contents were mostly uniform. H. stipulacea displayed a well conserved core bacteriome, as assessed by 454-pyrosequencing of 16S rRNA gene reads amplified from metagenomic DNA. The core bacteriome aboveground (leaves) and belowground (roots and rhizomes), was composed of more than 100 Operational Taxonomic Units (OTUs) representing 63% and 52% of the total community in each plant compartment, respectively, with a high incidence of the classes Alphaproteobacteria, Gammaproteobacteria and Deltaproteobacteria across all depths. Above and belowground communities were different and showed higher within-depth variability at the intermediate depths (9 and 18 m) than at the edges. Plants parts showed a clear influence in shaping the communities while depth showed a greater influence on the belowground communities. Overall, results highlighted a different ecological status of the H. stipulacea at the edges of the gradient (4-28 m), where plants showed not only marked differences in morphology and biochemistry, but also the most distinct associated bacterial consortium. We demonstrated the pivotal role of morphology, biochemistry (pigment and phenol content) and epiphytic bacterial communities in helping plants to cope with environmental and ecological variations. The plant/holobiont capability to persist and adapt to environmental changes likely has a pivotal role in its ecological resilience and invasiveness.

41 citations