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Lesion detection and signal–to–noise ratio in CT images
Medical Physics, 1981This study measured observers’ ability to detect and locate focal lesions on simulated CT images. The difficulty of the detection task was manipulated by changing the difference in attenuation between the lesion and its background (contrast), the random variation in the CT values (noise) or the lesion's size.
P F, Judy, R G, Swensson, M, Szulc
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Signal-to-noise ratio in correlation plenoptic imaging
Quantum Technologies 2020, 2020We review the signal-to-noise properties of two setups for Correlation Plenoptic Imaging (CPI), a novel technique that exploits the correlations of light intensity to perform the typical tasks of plenoptic imaging: refocusing out-of- focus parts of the scene, extending the depth of field, reconstruct 3D objects, As opposed to first-order plenoptic ...
Giovanni Scala +5 more
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Single Image Signal-to-Noise Ratio Estimation for Magnetic Resonance Images
Journal of Medical Systems, 2009A novel technique to quantify the signal-to-noise ratio (SNR) of magnetic resonance images is developed. The image SNR is quantified by estimating the amplitude of the signal spectrum using the autocorrelation function of just one single magnetic resonance image.
K S, Sim, M A, Lai, C P, Tso, C C, Teo
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Measuring signal-to-noise ratios in MR imaging.
Radiology, 1989The signal-to-noise ratio (S/N) in magnetic resonance imagining is one of the variables that must be measured when comparing the relative performance of different techniques. Although various investigators and official groups have proposed different methods for measuring S/N, these are generally not practical for use by a physician working in a ...
L, Kaufman +3 more
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Signal-to-noise ratio in coded aperture imaging
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2012Abstract We present a derivation of the signal-to-noise ratio (SNR) of a cyclic difference set (CDS) based coded mask which is simpler than that given in the literature, and which applies to any distribution of flux against the mask, not just Poisson statistics as is currently the case.
Paul M.E. Shutler +2 more
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Effective signal-to-noise ratio improvement by parametric image amplification
Optics Letters, 2006We show experimentally that parametric optical preamplification greatly improves the signal-to-noise ratio of an image if the detector has a poor quantum efficiency and/or a great level of readout noise. Results are fully consistent with the theory of quantum-noise-limited amplification.
Devaux, F., Blanchet, J.L., Lantz, E.
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Signal-to-noise ratios for attenuation correction in PET imaging
IEEE Transactions on Medical Imaging, 1994Attenuation correction is an important part of accurate image reconstruction in positron tomography. The usual correction method involves direct measurement of attenuation correction factors (ACFs). A reconstruct-reproject method, which has been suggested as providing superior noise properties, is sometimes employed; an attenuation image is first ...
B A, McKee, L G, Hiltz, P J, Harvey
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Improving Image Formation by Pushing the Signal-to-Noise Ratio
2010Two-photon and confocal laser scanning microscopes represent fundamental optical techniques for biological investigations, thanks to their optical sectioning capability. However, in several experimental situations, low-intensity signals are detected, and the imaging quality can be remarkably limited by noise contribution.
Ronzitti E. +3 more
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Signal-to-noise ratios of coherent imaging ladar
SPIE Proceedings, 2007We analyze the signal and noise in coherent active laser imaging systems (LADARs). The principle LADAR noise sources are shot noise in the detection process and target fluctuations in the reflected signal including speckle. The statistical relationships between signal and noise are similar for RADAR and LADAR.
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Signal-to-noise ratios in acousto-photonic imaging
SPIE Proceedings, 2006The concept of tagging photons with ultrasound for medical imaging has been under development by several groups since the early 1990's. All the early attempts were plagued by low signals. The problem is very fundamental because the goal of good spatial resolution requires sampling only that light which has gone through a very small volume.
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