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Image Enhancement (image + enhancement)
Selected AbstractsImage enhancement in ultramicroscopy by improved laser light sheetsJOURNAL OF BIOPHOTONICS, Issue 10-11 2010Saiedeh Saghafi Abstract In the majority of implementations of light sheet microscopy, such as ultramicroscopy, the laser beam illuminating the specimen is truncated by a slit aperture before it is focused to a light sheet by a single cylindrical lens. A light sheet generated in this way can be made very thin near to the focal point, but unfortunately its Rayleigh range is severely limited. This problem can be partially solved by using a smaller slit aperture. However, this also causes a major loss in power, a severe broadening of the beam waist, and thus a significant loss of resolution along the detection axis. We developed improved light-sheet-generation optics, which provide longer Raleigh ranges, whilst retaining beam waists comparable to our standard system with one cylindrical lens. Using the modified system we achieved a marked improvement in the resolution of ultramicroscopy reconstructions of representative biological specimens. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Ridge directional singular points for fingerprint recognition and matchingAPPLIED STOCHASTIC MODELS IN BUSINESS AND INDUSTRY, Issue 1 2006Issam Dagher Abstract In this paper, a new approach to extract singular points in a fingerprint image is presented. It is usually difficult to locate the exact position of a core or a delta due to the noisy nature of fingerprint images. These points are the most widely used for fingerprint classification and matching. Image enhancement, thinning, cropping, and alignment are used for minutiae extraction. Based on the Poincaré curve obtained from the directional image, our algorithm extracts the singular points in a fingerprint with high accuracy. It examines ridge directions when singular points are missing. The algorithm has been tested for classification performance on the NIST-4 fingerprint database and found to give better results than the neural networks algorithm. Copyright © 2005 John Wiley & Sons, Ltd. [source] Counterfeiting in performance- and image-enhancing drugsDRUG TESTING AND ANALYSIS, Issue 3 2009Michael R. Graham Abstract The current drastic escalation in obesity may be contributing to the exponential rise in drugs used for image enhancement. Drugs such as anabolic-androgenic steroids (AAS) are perceived as a viable method of achieving a perfect physique. They are also the most widely abused drugs in sport. The Internet has encouraged the abuse of expensive drugs, particularly human growth hormone (hGH), resulting in increased importation for personal use. The substantial increase in this market has opened up avenues for counterfeiting, estimated as a multi-million pound business. The acute adverse effects from contaminated vials may result in a variety of pathologies including communicable diseases. In 2007, in the UK, a series of intramuscular abscesses, requiring surgical treatment, led us to study samples obtained from the underground market. The analysis of 38 parenteral samples and 19 oral samples of tablets was performed by a World Anti-Doping Agency (WADA) accredited laboratory, in an attempt to establish the extent of available counterfeit products. Fifty-three per cent (20) of the injectable AAS esters and 21% (4) of the oral tablets were counterfeit. Culture and sensitivity revealed the presence of skin commensal organisms, which may have contributed to the development of the abscesses. Users of AAS and hGH for sport, including bodybuilding, are currently risking their health because of counterfeit and poorly controlled products. Copyright © 2009 John Wiley & Sons, Ltd. [source] SAR imaging using multidimensional continuous wavelet transform and applications to polarimetry and interferometryINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 5 2004E. Colin Abstract Usual SAR imaging process makes the assumption that the reflectors are isotropic and white (i.e., they behave in the same way regardless the angle from which they are viewed and the emitted frequency within the bandwidth). The multidimensional continuous wavelet transform (CWT) in radar imaging was initially developed to highlight the image degradations due to these assumptions. In this article the wavelet transform method is widened to polarimetry and interferometry fields. The wavelet tool is first used for polarimetric image enhancement, then for coherence optimization in interferometry. This optimization by wavelets, compared with the polarimetric one, gives better results on the coherence level. Finally, a combination of both methods is proposed. © 2005 Wiley Periodicals Inc. Int J Imaging Syst Technol, 14, 206,212, 2004; Published online in Wiley Inter-Science (www.interscience.wiley.com). DOI 10.1002/ima.20025 [source] Target image enhancement using representative line in MR cholangiography imagesINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 3 2004Syoji Kobashi Abstract MR cholangiography (MRC) is a commonly used imaging method for diagnosing the pancreatic duct. This article proposes a novel method for enhancing medical images called target image enhancement using representative line (TIER), and its application to MRC images. Our method first finds the representative line (RL) of the pancreatic duct using a fuzzy if-then rule. TIER presumes the approximate region of the pancreatic duct using the obtained RL, and then emphasizes the intensity in the approximate region. Therefore, our method does not require any segmentation procedures, which often may be hard work. We evaluated the ability to find the RL and to estimate the approximate region of the pancreatic duct by applying the proposed method to computer-simulated data and MRI phantom data. We also show the image-enhanced images for normal and abnormal patients. © 2004 Wiley Periodicals, Inc. Int J Imaging Syst Technol 14, 122,130, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.20015 [source] Sonographic examination of the oral phase of swallowing: Bolus image enhancementJOURNAL OF CLINICAL ULTRASOUND, Issue 2 2002Michael J. Casas DDS Abstract Purpose The purpose of this study was to evaluate the ability of 4 liquid boluses to enhance pixel brightness and the ease with which the boluses could be identified during the sonographic evaluation of oral swallowing in healthy young adults. Methods Ten healthy adult volunteers (5 men and 5 women), ranging in age from 21 to 31 years, underwent sonographic evaluation of the oral phase of swallowing while sitting in their usual feeding position. We compared the ability of the 4 following liquids to improve sonographic visualization of swallowing with that of water: a carbonated cola beverage, 5.0 ml of Thick-It in 120 ml of water, 2.5 ml of Thick-It in 120 ml of water, and 7.5 ml of confectioners' sugar in 120 ml of water. Water was used as a control. In each case, 5 ml of the liquid was introduced into the subject's oral cavity using a syringe, and the subject was instructed to swallow. Digitized still images and recorded video sequences of sonographic examinations of the swallowing were analyzed. The brightness of the bolus image on selected digitized video frames was measured digitally using Image Analyst software. Pixel brightness within selected regions of interest for each of the test liquids was statistically compared with that for water. Seven clinicians rated the visualization of each test liquid and water on paired sonographic videotape sequences. These ratings and the level of agreement between them were statistically tested. Results Only the carbonated cola beverage demonstrated statistically greater pixel brightness than that of water on digitized video frames (p = 0.01), whereas both cola (with a moderate inter-rater agreement, , = 0.50) and 5.0 ml Thick-It mixed with 120 ml of water (with a fair inter-rater agreement, , = 0.24) were significantly better visualized on sonographic video sequences. Conclusions The digital still-frame analysis confirmed the clinicians' ratings of bolus visualization on real-time sonography, but dynamic sonography is more important than still frames in assessing sonographic swallow media because the dynamic images more closely parallel what is seen in clinical practice. Future investigations of sonographic contrast agents for use in the examination of the oral phase of swallowing should use both static digital (still-frame) and dynamic (real-time) assessment methods, as well as expert reviewers. © 2002 John Wiley & Sons, Inc. J Clin Ultrasound 30:83,87, 2002; DOI 10.1002/jcu.10034 [source] | ||||||||||