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image/svg+xml Jakob Voss, based on art designer at PLoS, modified by Wikipedia users Nina and Beao Closed Access logo, derived from PLoS Open Access logo. This version with transparent background. http://commons.wikimedia.org/wiki/File:Closed_Access_logo_transparent.svg Jakob Voss, based on art designer at PLoS, modified by Wikipedia users Nina and Beao Medical Physicsarrow_drop_down
image/svg+xml Jakob Voss, based on art designer at PLoS, modified by Wikipedia users Nina and Beao Closed Access logo, derived from PLoS Open Access logo. This version with transparent background. http://commons.wikimedia.org/wiki/File:Closed_Access_logo_transparent.svg Jakob Voss, based on art designer at PLoS, modified by Wikipedia users Nina and Beao
Medical Physics
Article . 1994 . Peer-reviewed
License: Wiley Online Library User Agreement
Data sources: Crossref
Medical Physics
Article . 1995
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Noise analysis in real‐time portal imaging. I. Quantization noise

Authors: R, Rajapakshe; S, Shalev;

Noise analysis in real‐time portal imaging. I. Quantization noise

Abstract

The limit at which quantization noise becomes dominant in video‐based real‐time portal imaging has been studied. Quantization noise due to truncation in integer frame averaging is shown to be dominant over the input analog‐to‐digital converter (A/D) quantization noise, unless image addition is used in video‐based real‐time portal imaging systems. Portal images acquired with the Newvicon camera by averaging more than 64 frames are found to be dominated by the quantization noise due to truncation. It has shown that the signal‐to‐noise ratio (SNR) is limited to 886.8 when using an 8‐bit A/D with digital frame averaging, but higher values can be achieved with digital frame addition. It is also shown that digital frame addition together with 16‐bit processing can achieve higher contrast resolution than digital frame averaging and 8‐bit processing.

Keywords

Radiography, X-Rays, Humans, Gadolinium, Models, Theoretical, Mathematics

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selected citations
These citations are derived from selected sources.
This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Citations provided by BIP!
popularity
This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.
BIP!Popularity provided by BIP!
influence
This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Influence provided by BIP!
impulse
This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.
BIP!Impulse provided by BIP!
10
Average
Top 10%
Top 10%
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