Gideon Frieder

Learn More
In many three-dimensional imaging applications the three-dimensional scene is represented by a three-dimensional array of volume elements, or voxels for short. A subset Q of the voxels is specified by some property. The objects in the scene are then defined as subsets of Q formed by voxels which are “connected” in some appropriate sense. It is(More)
We review a variety of techniques to improve efficiency in information retrieval. Given the increasing volumes of data that are available electronically, understanding and using such techniques is critical. We address several efficiency concerns, but our primary focus is on index processing since it dominates the computational demands of information(More)
This paper presents an introduction to the field of three-dimensional medical imaging It presents medical imaging terms and concepts, summarizes the basic operations performed in three-dimensional medical imaging, and describes sample algorithms for accomplishing these operations. The paper contains a synopsis of the architectures and algorithms used in(More)
With the advent of medical imaging devices such as computed tomography, positron emission tomography, single photon emission computed tomography, magnetic resonance imaging, and ultrasound scanners, methods are widely available for capturing the shape and other properties of real objects (human organs) directly in machine-readable form. One way of(More)
We have developed a computer-resident stereotactic atlas of the human brain that quantitatively defines subcortical structures within anatomical landmarks detected on obliquely reconstructed computed tomography (CT) slices. Horizontal stereotactic atlas sections can be stretched and contracted by polar transformation and labeled by a computer to fit within(More)
Yizkor Book collections contain firsthand commemorative accounts of events from the era surrounding the rise and fall of Nazi Germany, including documents from before, during, and after the Holocaust. Prior to our effort, information regarding the content and location of each Yizkor Book volume was limited. We established a centralized index and metadata(More)
Degraded documents are frequently obtained in various situations. Examples of degraded document collections include historical document depositories, document obtained in legal and security investigations, and legal and medical archives. Degraded document images are hard to to read and are hard to analyze using computerized techniques. There is hence a need(More)
The United States Holocaust Memorial Museum (USHMM) recently celebrated its ten-year anniversary. The museum was established to bear witness to the human atrocities committed by the Nazi reign of terror. As such, related data must be collected, and means to store, search, and analyze the data must be provided. Presently, the data available reside in various(More)
—Document enhancement tools are a valuable help in the study of historic documents. Given proper filter settings, many effects that impair the legibility can be evened out (e.g. washed out ink, stained and yellowed paper). However, because of differing authors, languages, handwritings, fonts and paper conditions, no single filter parameter set fits all(More)