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Image Information (image + information)

Distribution by Scientific Domains
Humanities and Social Sciences50%

Selected Abstracts

Image reconstructions from two orthogonal projections

INTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 2 2003
Yuanmei Wang
Abstract A vector entropy optimization-based neural network approach is presented to handle image reconstructions from two orthogonal projections. An accurate and parallel reconstruction is attained with this method allowing parallel implementation. This is an attempt to extract the image information from two projections. It is especially meaningful for clinical applications and three-dimensional modeling of the coronary arteries. © 2003 Wiley Periodicals, Inc. Int J Imaging Syst Technol 13, 141,145, 2003; Published online in Wiley Inter-Science (www.interscience.wiley.com). DOI 10.1002/ima.10036 [source]

Position-dependent defocus processing for acoustic holography images

INTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 3 2002
Ruming Yin
Acoustic holography is a transmission-based ultrasound imaging method that uses optical image reconstruction and provides a larger field of view than pulse-echo ultrasound imaging. A focus parameter controls the position of the focal plane along the optical axis, and the images obtained contain defocused content from objects not near the focal plane. Moreover, it is not always possible to bring all objects of interest into simultaneous focus. In this article, digital image processing techniques are presented to (1) identify a "best focused" image from a sequence of images taken with different focus settings and (2) simultaneously focus every pixel in the image through fusion of pixels from different frames in the sequence. Experiments show that the three-dimensional image information provided by acoustic holography requires position-dependent filtering for the enhancement step. It is found that filtering in the spatial domain is more computationally efficient than in the frequency domain. In addition, spatial domain processing gives the best performance. © 2002 Wiley Periodicals, Inc. Int J Imaging Syst Technol 12, 101,111, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.10017 [source]

Mountain permafrost distribution modelling using a multi-criteria approach in the Hövsgöl area, northern Mongolia,,

PERMAFROST AND PERIGLACIAL PROCESSES, Issue 2 2006
Bernd Etzelmüller
Abstract Lake Hövsgöl is located on the southern fringe of the continuous permafrost zone in northern Mongolia. This paper describes a GIS-based empirical permafrost model that is calibrated with ground temperature observations, and utilises a multi-criteria approach to derive zones of permafrost favourability based on terrain parameters and land cover information. The scores are derived either by logistic regression or from satellite image information. The model is validated by DC resistivity tomography measurements. The overall permafrost distribution in the study area is well-described and the method appears to be a valid approach for mapping permafrost at both local and regional scales in mountain areas with low data coverage. Copyright © 2006 John Wiley & Sons, Ltd. [source]

A NEW TRUE ORTHO-PHOTO METHODOLOGY FOR COMPLEX ARCHAEOLOGICAL APPLICATION

ARCHAEOMETRY, Issue 3 2010
YAHYA ALSHAWABKEH
Ortho-photo is one of the most important photogrammetric products for archaeological documentation. It consists of a powerful textured representation combining geometric accuracy with rich detail, such as areas of damage and decay. Archaeological applications are usually faced with complex object shapes. Compared with conventional algorithms, ortho-projection of such rough curved objects is still a problem, due to the complex description of the analytical shape of the object. Even using a detailed digital surface model, typical ortho-rectification software does not produce the desired outcome, being incapable of handling image visibility and model occlusions, since it is limited to 2.5-dimensional surface descriptions. This paper presents an approach for the automated production of true ortho-mosaics for the documentation of cultural objects. The algorithm uses precise three-dimensional surface representations derived from laser scanning and several digital images that entirely cover the object of interest. After identifying all model surface triangles in the viewing direction, the triangles are projected back on to all initial images to establish visibilities for every available image. Missing image information can be filled in from adjacent images that must have been subjected to the same true ortho-photo procedure. [source]