Computer analysis of mammography phantom images (CAMPI): An application to the measurement of microcalcification image quality of directly acquired digital images

1997 ◽  
Vol 24 (8) ◽  
pp. 1269-1277 ◽  
Author(s):  
Dev P. Chakraborty
Keyword(s):  
Image Quality ◽  
Computer Analysis ◽  
Digital Images

Digital Imaging for Photographic Collections: Foundations for Technical Standard

2000 ◽  
Vol 29 (1) ◽  
Author(s):  
Robin Dale
Keyword(s):  
Image Quality ◽  
Digital Imaging ◽  
Digital Images ◽  
National Endowment ◽  
Technical Standard ◽  
Digital Form ◽  
Project Report

The goal of this project report, sponsored by The National Endowment for the Humanities, Division of Preservation and Access, is “to offer some guidance to libraries, archives, and museums in their efforts to convert photographic collections to digital form.” To date, there are no standards for measuring the quality of digital images created from photographs. Therefore, this report is primarily concerned with developing tools to measure image quality. Other technical and managerial issues related to digital imaging projects in general are also addressed.

Evaluation of digital and film hemispherical photography and spherical densiometry for measuring forest light environments

2000 ◽  
Vol 30 (12) ◽  
pp. 1999-2005 ◽  
Author(s):  
Sylvia R Englund ◽  
Joseph J O'Brien ◽  
David B Clark
Keyword(s):  
Image Quality ◽  
Computer Analysis ◽  
Digital Image ◽  
Digital Images ◽  
Optical Quality ◽  
Field Of View ◽  
Canopy Openness ◽  
Hemispherical Photography ◽  
Site Factor ◽  
Film Images

This study presents the results of a comparison of digital and film hemispherical photography as means of characterizing forest light environments and canopy openness. We also compared hemispherical photography to spherical densiometry. Our results showed that differences in digital image quality due to the loss of resolution that occurred when images were processed for computer analysis did not affect estimates of unweighted openness. Weighted openness and total site factor estimates were significantly higher in digital images compared with film photos. The differences between the two techniques might be a result of underexposure of the film images or differences in lens optical quality and field of view. We found densiometer measurements significantly increased in consistency with user practice and were correlated with total site factor and weighted-openness estimates derived from hemispherical photography. Digital photography was effective and more convenient and inexpensive than film cameras, but until the differences we observed are better explained, we recommend caution when comparisons are made between the two techniques. We also concluded that spherical densiometers effectively characterize forest light environments.

High-quality Multi-level Error Diffusion Method Employing Fuzzy Inference

2003 ◽  
Vol 7 (2) ◽  
pp. 235-243 ◽  
Author(s):  
Noriaki Suetake ◽  
◽  
Masanori Togashi ◽  
Keyword(s):  
Image Quality ◽  
Conventional Method ◽  
Fuzzy Inference ◽  
Digital Images ◽  
Diffusion Method ◽  
Error Diffusion ◽  
High Quality ◽  
Multi Level

We propose a new multi-level error diffusion method employing the fuzzy inference, which realizes half toning with high quality. In the proposed method, dissimilar textures around quantization levels, which are the cause of the low image quality and obtained by a conventional method, are decreased by using fuzzy inference. In this paper, we apply the proposed method to various standard digital images. The image quality of the result using the proposed method is higher than those of other methods without noise-add filtering, and it is almost same as them with filtering in 2 or 3 times faster processing.

scholarly journals Designing an Herbarium Digitisation Workflow with Built-In Image Quality Management

2020 ◽  
Vol 8 ◽  
Author(s):  
Abraham Nieva de la Hidalga ◽  
Paul Rosin ◽  
Xianfang Sun ◽  
Ann Bogaerts ◽  
Niko De Meeter ◽  
...  
Keyword(s):  
Image Quality ◽  
Modular Design ◽  
Image Quality Assessment ◽  
Digital Images ◽  
Quality Criteria ◽  
Audit Trail ◽  
Large Numbers ◽  
Strong Focus ◽  
Standards And Guidelines

Digitisation of natural history collections has evolved from creating databases for the recording of specimens’ catalogue and label data to include digital images of specimens. This has been driven by several important factors, such as a need to increase global accessibility to specimens and to preserve the original specimens by limiting their manual handling. The size of the collections pointed to the need of high throughput digitisation workflows. However, digital imaging of large numbers of fragile specimens is an expensive and time-consuming process that should be performed only once. To achieve this, the digital images produced need to be useful for the largest set of applications possible and have a potentially unlimited shelf life. The constraints on digitisation speed need to be balanced against the applicability and longevity of the images, which, in turn, depend directly on the quality of those images. As a result, the quality criteria that specimen images need to fulfil influence the design, implementation and execution of digitisation workflows. Different standards and guidelines for producing quality research images from specimens have been proposed; however, their actual adaptation to suit the needs of different types of specimens requires further analysis. This paper presents the digitisation workflow implemented by Meise Botanic Garden (MBG). This workflow is relevant because of its modular design, its strong focus on image quality assessment, its flexibility that allows combining in-house and outsourced digitisation, processing, preservation and publishing facilities and its capacity to evolve for integrating alternative components from different sources. The design and operation of the digitisation workflow is provided to showcase how it was derived, with particular attention to the built-in audit trail within the workflow, which ensures the scalable production of high-quality specimen images and how this audit trail ensures that new modules do not affect either the speed of imaging or the quality of the images produced.

scholarly journals Image quality assessment

2022 ◽  
pp. 4-15
Author(s):  
Y. I. Golub
Keyword(s):  
Image Quality ◽  
Quality Assessment ◽  
Image Quality Assessment ◽  
Digital Images ◽  
Image Databases ◽  
Automated Systems ◽  
Digital Formats ◽  
Proximity Measures ◽  
Visual Assessments

Quality assessment is an integral stage in the processing and analysis of digital images in various automated systems. With the increase in the number and variety of devices that allow receiving data in various digital formats, as well as the expansion of human activities in which information technology (IT) is used, the need to assess the quality of the data obtained is growing. As well as the bar grows for the requirements for their quality.The article describes the factors that deteriorate the quality of digital images, areas of application of image quality assessment functions, a method for normalizing proximity measures, classes of digital images and their possible distortions, image databases available on the Internet for conducting experiments on assessing image quality with visual assessments of experts.

Observability of Very Thick Specimen by Using Transmission Scanning Electron Microscope

1971 ◽  
Vol 29 ◽  
pp. 26-27
Author(s):  
K. Shibatomi ◽  
T. Yamanoto ◽  
H. Koike
Keyword(s):  
Electron Microscope ◽  
Image Quality ◽  
Scanning Electron Microscope ◽  
Chromatic Aberration ◽  
Image Contrast ◽  
Objective Lens ◽  
Thick Specimen ◽  
Transmission Electron ◽  
Scanning Electron

In the observation of a thick specimen by means of a transmission electron microscope, the intensity of electrons passing through the objective lens aperture is greatly reduced. So that the image is almost invisible. In addition to this fact, it have been reported that a chromatic aberration causes the deterioration of the image contrast rather than that of the resolution. The scanning electron microscope is, however, capable of electrically amplifying the signal of the decreasing intensity, and also free from a chromatic aberration so that the deterioration of the image contrast due to the aberration can be prevented. The electrical improvement of the image quality can be carried out by using the fascionating features of the SEM, that is, the amplification of a weak in-put signal forming the image and the descriminating action of the heigh level signal of the background. This paper reports some of the experimental results about the thickness dependence of the observability and quality of the image in the case of the transmission SEM.

Organ doses and subjective image quality of indirect digital panoramic radiography

2001 ◽  
Vol 30 (6) ◽  
pp. 308-313 ◽  
Author(s):  
F Gijbels ◽  
G Sanderink ◽  
C Bou Serhal ◽  
H Pauwels ◽  
R Jacobs
Keyword(s):  
Image Quality ◽  
Panoramic Radiography ◽  
Organ Doses ◽  
Subjective Image Quality ◽  
Digital Panoramic Radiography
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