|
Shepp–Logan Phantom
The Shepp–Logan phantom is a standard test image created by Larry Shepp and Benjamin F. Logan for their 1974 paper ''The Fourier Reconstruction of a Head Section''. It serves as the model of a human head in the development and testing of image reconstruction algorithms. Definition The function describing the phantom is defined as the sum of 10 ellipses inside a 2×2 square: References See also *Imaging phantom Imaging phantom, or simply phantom, is a specially designed object that is scanned or imaged in the field of medical imaging to evaluate, analyze, and tune the performance of various imaging devices. A phantom is more readily available and prov ... {{DEFAULTSORT:Shepp-Logan phantom Image processing 1974 works Test items ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standard Test Image
A standard test image is a digital image file used across different institutions to test image processing and image compression algorithms. By using the same standard test images, different labs are able to compare results, both visually and quantitatively. The images are in many cases chosen to represent natural or typical images that a class of processing techniques would need to deal with. Other test images are chosen because they present a range of challenges to image reconstruction algorithms, such as the reproduction of fine detail and textures, sharp transitions and edges, and uniform regions. Historical origins Test images as transmission system calibration material probably date back to the original Paris to Lyon fax link. Analogue Fax equipment (and photographic equipment for the printing trade) were the largest user groups of the standardized image for calibration technology until the coming of television and digital image transmission systems. Common test image ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Larry Shepp
Lawrence Alan Shepp (September 9, 1936 Brooklyn, NY – April 23, 2013, Tucson, AZ) was an American mathematician, specializing in statistics and computational tomography. Shepp obtained his PhD from Princeton University in 1961 with a dissertation entitled ''Recurrent Sums of Random Variables''. His advisor was William Feller. He joined Bell Laboratories in 1962. He joined Rutgers University in 1997. He joined University of Pennsylvania in 2010. His work in tomography has had biomedical imaging applications, and he has also worked as professor of radiology at Columbia University (1973–1996), as a mathematician in the radiology service of Columbia Presbyterian Hospital. Awards and honors * 2014: IEEE Marie Sklodowska-Curie Award * 2012: Became a fellow of the American Mathematical Society. * 1992: Elected member of the Institute of Medicine * 1989: Elected member of the National Academy of Sciences * 1979: IEEE Distinguished Scientist Award in 1979 * 1979: Lester R. Ford ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benjamin F
Benjamin ( he, ''Bīnyāmīn''; "Son of (the) right") blue letter bible: https://www.blueletterbible.org/lexicon/h3225/kjv/wlc/0-1/ H3225 - yāmîn - Strong's Hebrew Lexicon (kjv) was the last of the two sons of Jacob and Rachel (Jacob's thirteenth child and twelfth and youngest son) in Jewish, Christian and Islamic tradition. He was also the progenitor of the Israelite Tribe of Benjamin. Unlike Rachel's first son, Joseph, Benjamin was born in Canaan according to biblical narrative. In the Samaritan Pentateuch, Benjamin's name appears as "Binyamēm" ( Samaritan Hebrew: , "son of days"). In the Quran, Benjamin is referred to as a righteous young child, who remained with Jacob when the older brothers plotted against Joseph. Later rabbinic traditions name him as one of four ancient Israelites who died without sin, the other three being Chileab, Jesse and Amram. Name The name is first mentioned in letters from King Sîn-kāšid of Uruk (1801–1771 BC), who called himself “K ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Image Reconstruction
Iterative reconstruction refers to iterative algorithms used to reconstruct 2D and 3D images in certain imaging techniques. For example, in computed tomography an image must be reconstructed from projections of an object. Here, iterative reconstruction techniques are usually a better, but computationally more expensive alternative to the common filtered back projection (FBP) method, which directly calculates the image in a single reconstruction step.Herman, G. T.Fundamentals of computerized tomography: Image reconstruction from projection 2nd edition, Springer, 2009 In recent research works, scientists have shown that extremely fast computations and massive parallelism is possible for iterative reconstruction, which makes iterative reconstruction practical for commercialization. Basic concepts The reconstruction of an image from the acquired data is an inverse problem. Often, it is not possible to exactly solve the inverse problem directly. In this case, a direct algorithm h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wired (website)
''Wired'' (stylized as ''WIRED'') is a monthly American magazine, published in print and online magazine, online editions, that focuses on how emerging technologies affect culture, the economy, and politics. Owned by Condé Nast, it is headquartered in San Francisco, California, and has been in publication since March/April 1993. Several spin-offs have been launched, including ''Wired UK'', ''Wired Italia'', ''Wired Japan'', and ''Wired Germany''. From its beginning, the strongest influence on the magazine's editorial outlook came from founding editor and publisher Louis Rossetto. With founding creative director John Plunkett, Rossetto in 1991 assembled a 12-page prototype, nearly all of whose ideas were realized in the magazine's first several issues. In its earliest colophon (publishing), colophons, ''Wired'' credited Canadian media theorist Marshall McLuhan as its "patron saint". ''Wired'' went on to chronicle the evolution of digital technology and its impact on society. ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Resonance In Medicine
''Magnetic Resonance in Medicine'' is a monthly peer-reviewed medical journal covering research on all aspects of the development and use of nuclear magnetic resonance and electron paramagnetic resonance techniques for medical applications. It was established in 1984 and is published by Wiley Wiley may refer to: Locations * Wiley, Colorado, a U.S. town * Wiley, Pleasants County, West Virginia, U.S. * Wiley-Kaserne, a district of the city of Neu-Ulm, Germany People * Wiley (musician), British grime MC, rapper, and producer * Wiley Mil ... on behalf of thInternational Society for Magnetic Resonance in Medicine External links *{{Official website, http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1522-2594 Medical physics journals Monthly journals Wiley-Blackwell academic journals English-language journals Publications established in 1984 Radiology and medical imaging journals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ellipse
In mathematics, an ellipse is a plane curve surrounding two focus (geometry), focal points, such that for all points on the curve, the sum of the two distances to the focal points is a constant. It generalizes a circle, which is the special type of ellipse in which the two focal points are the same. The elongation of an ellipse is measured by its eccentricity (mathematics), eccentricity e, a number ranging from e = 0 (the Limiting case (mathematics), limiting case of a circle) to e = 1 (the limiting case of infinite elongation, no longer an ellipse but a parabola). An ellipse has a simple algebraic solution for its area, but only approximations for its perimeter (also known as circumference), for which integration is required to obtain an exact solution. Analytic geometry, Analytically, the equation of a standard ellipse centered at the origin with width 2a and height 2b is: : \frac+\frac = 1 . Assuming a \ge b, the foci are (\pm c, 0) for c = \sqrt. The standard parametric e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imaging Phantom
Imaging phantom, or simply phantom, is a specially designed object that is scanned or imaged in the field of medical imaging to evaluate, analyze, and tune the performance of various imaging devices. A phantom is more readily available and provides more consistent results than the use of a living subject or cadaver, and likewise avoids subjecting a living subject to direct risk. Phantoms were originally employed for use in 2D x-ray based imaging techniques such as radiography or fluoroscopy, though more recently phantoms with desired imaging characteristics have been developed for 3D techniques such as SPECT, MRI, CT, Ultrasound, PET, and other imaging methods or modalities. Design A phantom used to evaluate an imaging device should respond in a similar manner to how human tissues and organs would act in that specific imaging modality. For instance, phantoms made for 2D radiography may hold various quantities of x-ray contrast agents with similar x-ray absorbing properties to n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Image Processing
An image is a visual representation of something. It can be two-dimensional, three-dimensional, or somehow otherwise feed into the visual system to convey information. An image can be an artifact, such as a photograph or other two-dimensional picture, that resembles a subject. In the context of signal processing, an image is a distributed amplitude of color(s). In optics, the term “image” may refer specifically to a 2D image. An image does not have to use the entire visual system to be a visual representation. A popular example of this is of a greyscale image, which uses the visual system's sensitivity to brightness across all wavelengths, without taking into account different colors. A black and white visual representation of something is still an image, even though it does not make full use of the visual system's capabilities. Images are typically still, but in some cases can be moving or animated. Characteristics Images may be two or three-dimensional, such as a pho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1974 Works
Major events in 1974 include the aftermath of the 1973 oil crisis and the resignation of President of the United States, United States President Richard Nixon following the Watergate scandal. In the Middle East, the aftermath of the 1973 Yom Kippur War determined politics; following List of Prime Ministers of Israel, Israeli Prime Minister Golda Meir's resignation in response to high Israeli casualties, she was succeeded by Yitzhak Rabin. In Europe, the Turkish invasion of Cyprus, invasion and occupation of northern Cyprus by Turkey, Turkish troops initiated the Cyprus dispute, the Carnation Revolution took place in Portugal, and Chancellor of Germany, Chancellor of West Germany Willy Brandt resigned following an Guillaume affair, espionage scandal surrounding his secretary Günter Guillaume. In sports, the year was primarily dominated by the 1974 FIFA World Cup, FIFA World Cup in West Germany, in which the Germany national football team, German national team won the championshi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
