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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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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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Imaging through turbulence: Degradation of signal-to-noise ratio
Optics Communications, 1984Abstract In this paper, we formulate the signal-to-noise ratio (SNR) of a direct-detection imaging system in turbulent media. From the formulation, we find that the SNR varies in the image plane and that the object radiation pattern affects SNR dramatically. An example is given to demonstrate the turbulence effect on the degradation of SNR.
S.J. Wang, M.A. Plonus
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Image-Adaptive Watermarking Using the Improved Signal to Noise Ratio
2006 International Conference on Computational Intelligence and Security, 2006This paper presents a new perceptual quality metric (PQM), the improved signal to noise ratio (iSNR). The improvement is done in the following two aspects: 1) the SNR manifests much better performance in an image block of small size than in a whole image; 2) the average luminance and gradient information are added into the SNR. Next, a locally adaptive
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Signal to noise ratio optimization of photorefractive image amplifiers
Nonlinear Optics: Materials, Fundamentals, and Applications, 1992After describing the sources of noise in photorefractive image amplifiers, we present different solutions to built amplifiers with large signal to noise ratio.
G. Pauliat +4 more
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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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Contrast signal-to-noise ratio for image quality assessment
IEEE International Conference on Image Processing 2005, 2005Peak signal-to-noise ratio (PSNR) is commonly used as an objective quality metric in signal processing. However, PSNR correlates poorly with the subjective quality rating. In this paper, we propose a new metric using contrast signal-to-noise ratio (CSNR), which measures the ratio of the contrast information level of distorted signal to the contrast ...
null Susu Yao +3 more
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An unbiased signal‐to‐noise ratio measure for magnetic resonance images
Medical Physics, 1993Estimating the true signal‐to‐noise ratio (SNR) of magnetic resonance (MR) images with low signal is confounded by the magnitude presentation of the data. This paper suggests a simple solution to this problem. A common method of measuring SNR compares the mean signal to the standard deviation of the noise.
G, McGibney, M R, Smith
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Accurate histopathology from low signal-to-noise ratio spectroscopic imaging data
The Analyst, 2010Fourier Transform Infrared (FT-IR) spectroscopic imaging is emerging as an automated alternative to human examination in studying development and disease in tissue. The technology's speed and accuracy, however, are limited by the trade-off with signal-to-noise ratio (SNR).
Rohith K, Reddy, Rohit, Bhargava
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Optimal signal-to-noise ratios for soft x-ray lensless imaging
Optics Letters, 2009We propose and demonstrate a method to gauge and optimize the signal-to-noise ratios (SNRs) in lensless imaging using partially coherent sources. Through spatial filtering we tuned the coherence width of an incoherent soft x-ray undulator source, and we deduce that there exists an optimal spatial filter setting for imaging micrometer-sized objects ...
R, Rick +5 more
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