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SIGNAL-TO-NOISE RATIO AS A CHARACTERISTIC OF IMAGE QUALITY
Quality. Innovation. Education, 2022The lack of clear requirements for the parameters of video surveillance systems provokes the presence of at least three significant problems discussed in this article. Their presence generates a significant contradiction between the image quality that is declared by the manufacturers of video surveillance systems, and the image quality that is expected
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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 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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Improving the signal-to-noise ratio in incoherent imaging
2021Imaging plays an important role in our modern world. Besides limitations in terms of resolution, all imaging systems show degrading image quality with increasing noise. Hence, an important aspect of any imaging application is the achievable signal-to-noise ratio (SNR). When neglecting typical noise sources (e.g. from detectors), we are left with a very
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Signal-to-noise ratio in a frequency multiplexing imager
IEEE Journal of Quantum Electronics, 1983The signal-to-noise ratio ( S/N ) to be expected in a frequency multiplexing imager is calculated. It is shown that, for an ideal detector, the S/N is comparable to the two-dimensional (2D) scanning imager. For low performance detectors, the frequency multiplexing imager is noticeably better, and in limiting cases, file S/N approaches that of a BLIP ...
N. Ben-Yosef, G. Sirat
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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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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 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 Ratio of Image Devices
1960Publisher Summary This chapter discusses the signal-to-noise ratio of image devices. In an X-ray image intensifier, the X-rays are absorbed in a fluorescent screen that converts the X-rays into light. The light quanta excite the photocathode, which is deposited upon the fluorescent material. In such cases, therefore, an image represented by X-rays is
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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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