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The article considers the possibility of controlling the brightness and contrast of the digital image by transformation of the pixel brightness through the power function. Analysis of the parameters of the converted images on the simple model of dark low contrast image has been carried out. The preferred values of parameters and possible ranges of brightness and contrast are determined. The results of transformation of the dark low contrast images compared with the results of image processing by other methods (approximated by reduction of a histogram to a uniform distribution and a television algorithm) are investigated. It has been stated that the parameters of the considered transformation can be chosen, so that the improvement of the distinguishability of the image details will be much better than using the methods with which the comparison is made.

Cattle in high-elevation rangelands experience cold and hot extremes. Given the increase in black hided cattle globally, thermoregulation options on rangelands, and hide color function affecting mammal thermal ecology, this study quantified winter albedo, external cattle temperatures (Tempcow), and differences (ΔT) between Tempcow and ambient air temperature (Tempamb), for different color cattle along a thermal gradient (≈−33 °C to +33 °C). From 2016 to 2018, I measured 638 individual Tempcow × Tempamb combinations for white (n = 183), red (n = 158), and black (n = 297) Bos taurus female cattle free roaming extensive Wyoming, USA rangelands. Pixel brightness of cow images relative to snow indicated mean (±standard error) albedo for white, red, and black cows (n = 3 of each) was 0.69 (±0.15), 0.16 (±0.04), and 0.04 (±0.01), respectively (p = 0.0027). Tempcow was explained by Tempamb (+), clear sky insolation index (+), and cow albedo (−). However, ΔT was explained by Tempamb (−), long-wave radiation (infrared, RadLW (−)), Tempcow (+), and cow albedo (+). Tempamb relative to ΔT was correlated for all hide colors (all p-values &lt, 0.0001, all r2 values &gt, 0.7)), yet slopes (m) were ~2× greater for red and black cows than white cows.

Automatic crack detection is a critical task that has the potential to drastically reduce labor-intensive building and road inspections currently being done manually. Recent studies in this field have significantly improved the detection accuracy. However, the methods often heavily rely on costly annotation processes. In addition, to handle a wide variety of target domains, new batches of annotations are usually required for each new environment. This makes the data annotation cost a significant bottleneck when deploying crack detection systems in real life. To resolve this issue, we formulate the crack detection problem as a weakly-supervised problem and propose a two-branched framework. By combining predictions of a supervised model trained on low quality annotations with predictions based on pixel brightness, our framework is less affected by the annotation quality. Experimental results show that the proposed framework retains high detection accuracy even when provided with low quality annotations. Implementation of the proposed framework is publicly available at https://github.com/hitachi-rd-cv/weakly-sup-crackdet., Accepted to ICPR 2020

Beyond simple identification of either the presence or absence of microplastic particles in the environment, quantitative accuracy has been criticised as being neither comparable nor reproducible. This is, in part, due to difficulties in the identification of synthetic particles amidst naturally occurring organic and inorganic components. The fluorescent stain Nile red has been proposed as a tool to overcome this issue, but to date, has been used without consideration of polymer specific fluorescent variability. The aim of this study was to evaluate the efficacy of Nile red for microplastic detection by systematically investigating what drives variations in particle pixel brightness (PPB). The results showed that PPB varied between polymer type, shape, size, colour and by staining procedure. Sand, an inorganic component of the sample matrix does not fluoresce when stained with Nile red. In contrast the organic components, wood and chitin, fluoresce between 1.40 and 12 arbitrary units (a.u.) and 32 and 74 a.u. after Nile red staining, respectively. These data informed the use of a PPB threshold limit of 100 a.u., which improved the detection of EPS, HDPE, PP and PA-6 from the 6 polymers tested and reduced analysis time by 30-58% compared to unstained samples. Conversely, as with traditional illumination, PET and PVC were not accurately estimated using this approach. This study shows that picking a threshold limit is not arbitrary but rather must be informed by polymer specific fluorescent variability and matrix considerations. This is an essential step needed to facilitate comparability and reproducibility between individual studies.

Mechanical damage of hair can serve as an indicator of health status and its assessment relies on the measurement of morphological features via microscopic analysis, yet few studies have categorized the extent of damage sustained, and instead have depended on qualitative profiling based on the presence or absence of specific features. We describe the development and application of a novel quantitative measure for scoring hair surface damage in scanning electron microscopic (SEM) images without predefined features, and automation of image analysis for characterization of morphological hair damage after exposure to an explosive blast. Application of an automated normalization procedure for SEM images revealed features indicative of contact with materials in an explosive device and characteristic of heat damage, though many were similar to features from physical and chemical weathering. Assessment of hair damage with tailing factor, a measure of asymmetry in pixel brightness histograms and proxy for surface roughness, yielded 81% classification accuracy to an existing damage classification system, indicating good agreement between the two metrics. Further ability of the tailing factor to score features of hair damage reflecting explosion conditions demonstrates the broad applicability of the metric to assess damage to hairs containing a diverse set of morphological features.

Background and Aims. Linked color imaging (LCI) helps screen and diagnose for early gastric cancer by color contrast in different mucosa. RGB (red, green, and blue) pixel brightness quantifies colors, which is relatively objective. Limited studies have combined LCI images with RGB to help screen for early gastric cancer (EGC). We aimed to evaluate the RGB pixel brightness characteristics of EGC and noncancer areas in LCI images. Methods. We retrospectively reviewed early gastric cancer (EGC) patients and LCI images. All pictures were evaluated by at least two endoscopic physicians. RGB pixel brightness analysis of LCI images was performed in MATLAB software to compare the cancer with noncancer areas. Receiver operating characteristic (ROC) curve was analyzed for sensitivity, specificity, cut-off, and area under the curve (AUC). Results. Overall, 38 early gastric cancer patients were enrolled with 38 LCI images. Pixel brightness of red, green, and blue in cancer was remarkably higher than those in noncancer areas (190.24±37.10 vs. 160.00±40.35, p<0.001; 117.96±33.91 vs. 105.33±30.01, p=0.039; 114.36±34.88 vs. 90.93±30.14, p<0.001, respectively). Helicobacter plyori (Hp) infection was not relevant to RGB distribution of EGC. Whether the score of Kyoto Classification of Gastritis (KCG) is ≥4 or p>0.05). Receiver operating characteristic (ROC) curve for differentiating cancer from noncancer was calculated. The maximum area under the curve (AUC) was 0.767 in B/G, with a sensitivity of 0.605, a specificity of 0.921, and a cut-off of 0.97. Conclusions. RGB pixel brightness was useful and more objective in distinguishing early gastric cancer for LCI images.

Many solar forecast algorithms based on ground based sky imagery apply the red-blue ratio (RBR) method to classify image pixels as clear or cloudy, by comparing the current image with the corresponding image from a clear sky library (CSL). The CSL needs to be updated regularly due to changes in clear sky readings over time caused by aerosols and imager dome properties. This clear sky library is typically created by visually scrutinizing daily sky videos and selecting appropriate clear sky periods. This practice takes a significant amount of time and manual intervention can result in human errors. To avoid this, an automated CSL algorithm (ACSL) was developed which filters each image for clear sky features including maximum green pixel brightness, average RBR, and red channel difference by pixel with respect to the previous image. The root mean square difference (RMSD) between the image RBR of the manually created CSL and the ACSL for November and April 2013 at UC San Diego were observed to be less than 6% over the full range of solar zenith angles. The ACSL was found to be more representative of clear conditions than its manual counterpart.

Purpose: To enhance the current standards of subclinical keratoconus screening based on the statistical modeling of the pixel intensity distribution of Scheimpflug images. Methods: Scheimpflug corneal tomographies corresponding to 25 corneal meridians of 60 participants were retrospectively collected and divided into three groups: controls (20 eyes), subclinical keratoconus (20 eyes), and clinical keratoconus (20 eyes). Only right eyes were selected. After corneal segmentation, pixel intensities of the stromal tissue were statistically modeled using a Weibull probability density function from which parameter a (pixel brightness) was derived. Further, data were transformed to polar coordinates, smoothed, and interpolated to build a map of the corneal a parameter. The discriminative power of the method was analyzed using receiver operating characteristic curves. Results: The proposed platform-independent method achieved a higher performance in discriminating subclinical keratoconus from control eyes (90.0% sensitivity, 95.0% specificity, 0.97 area under the curve [AUC]) than the standard method (Belin–Ambrósio enhanced ectasia display), which uses only corneal morphometry (85.0% sensitivity, 85.0% specificity, 0.80 AUC). Conclusions: Analysis of light backscatter at the cornea successfully discriminates subclinical keratoconus from control eyes, upgrading the results previously reported in the literature. Translational Relevance: The proposed methodology has the potential to support clinicians in the detection of keratoconus before showing clinical signs. © 2021 The Authors.

At the suggestion of the NASA Meteoroid Environment Office (NASA/MEO), which promotes lunar impact monitoring worldwide during NASA’s Lunar Atmosphere and Dust Environment Explorer (LADEE) mission period (launched Sept. 2013), we set up a video observation system for lunar impact flashes using a 16-inch educational telescope at Chungnam National University. From Oct. 2013 through Apr. 2014, we recorded 80 hours of video observation of the unilluminated part of the crescent moon in the evening hours. We found a plausible candidate impact flash on Feb. 3, 2014 at selenographic longitude 2.1° and latitude 25.4°. The flash lasted for 0.2 s and the light curve was asymmetric with a slow decrease after a peak brightness of 8.7 ± 0.3 mag. Based on a star-like distribution of pixel brightness and asymmetric light curve, we conclude that the observed flash was due to a meteoroid impact on the lunar surface. Since unequivocal detection of an impact flash requires simultaneous observation from at least two sites, we strongly recommend that other institutes and universities in Korea set up similar inexpensive monitoring systems involving educational or amateur telescopes, and that they collaborate in the near future.

In this paper, the approach of changing bit depth of images is considered. This type of operation is required when performing primary processing operations, identifying parameters and stitching images. The process of changing bits depth of images is performed in three stages. At each stage, the error minimization criterion is tested Result of applying the approach allows obtaining numerical region characteristics including the number of clusters, the number of minimum and maximum cluster sizes. To perform the process of minimizing some of the criteria, it is necessary to divide the image into areas. The paper presents a mathematical description of the approach, as well as flowcharts for performing operations of data processing steps. The article gives recommendations for choosing coefficients to obtain optimal minimizing parameters. The test images give an example of performing bit changes on image areas.

© 2017 IEEE. Commercial off-the-shelf 12-Megapixel CMOS image sensors were irradiated with 105 MeV protons - one part to a fluence of 4×1011 protons/cm2, and a second part to 2×1011 protons/cm2. Pixel brightness increases with fluence along with annealing effects are reported. No latch-up events or hangs occurred.

Results of a study of automatic recognition of pathological resorption zones in the image of the jawbone are presented. A criterion for the presence of pathological resorption in the bone is formulated based on statistical investigation. The pathological resorption search method is described as a sequence of algorithmic steps.

Improved color channel comparison method (ICCCM) is an effective method to transformcolor images into gray-scale ones. Based on the ICCCM, black or white insects could be effectively extracted and recognized from the real color images with bright background. Howeverit is difficult to use the ICCCM to extract and recognize the black insects from the realcolorimage with dark background. In this paper, the ICCCM is modified to transformthe color images into the gray ones, extracting and recognizing the black insectson the dark background. The ICCCM is modified as follows: (1) A threshold of the gray image is an average brightness value ofred (R), green (G) and blue (B) in all the image pixels.(2) The bright pixels and the color pixels have the highest brightness value 255 in the gray image.(3) A pixel brightness value of the dark area in the gray image equals to a minimum of R, G and B in the pixel. (4) After deleted all the pixels with a brightness value of 255, a threshold of the binary image is determined by Otsus theory. The modified ICCCM more effectively extracts and recognizes the black insects from the realcolorimages with dark background compared with the ICCCM.

Shot boundary detection is an essential step for efficient browsing, sorting, and classification of video data. Robust shot detection method should overcome the disturbances caused by pixel brightness and object movement between frames. In this paper, two shot boundary detection methods are presented to address these problem by using segmentation, object movement, and pixel brightness. The first method is based on the histogram that reflects object movements and the morphological dilation operation that considers pixel brightness. The second method uses the pixel brightness information of segmented and whole blocks between frames. Experiments on digitized video data of National Archive of Korea show that the proposed methods outperforms the existing pixel-based and histogram-based methods.

BackgroundThere is growing evidence that maximal surgical resection of primary intrinsic brain tumours is beneficial, both by improving progression free and overall survival and also by facilitating postoperative chemotherapy and radiotherapy. Hence, there has been an increase in the popularity of real-time intraoperative imaging in brain tumour surgery. The complex theatre arrangements, prohibitive cost and prolonged theatre time of intraoperative MRI have restricted its application. By comparison, intraoperative three-dimensional ultrasound (i3DUS) is user friendly, cost-effective and portable and adds little to surgical time. However, operator-dependent image quality and image interpretation remain limiting factors to the wider application of this technique. The aim of this study was to explore objective i3DUS image analysis and its potential therapeutic role in brain tumour surgery.MethodsA prospective, observational study was undertaken (approved by the local Research and Ethics Committee prior to recruitment). Biopsies were taken from the solid, necrotic, periphery and brain/tumour interface of intrinsic primary brain tumours. Digital i3DUS images were analysed to extract quantitative parameters from these regions of interest (ROI) in the i3DUS images. These were then correlated with the histology of the relevant specimens. The histopathologist was blinded to the imaging findings.ResultsNinety-seven patients (62 males; mean 54 years) with varying gliomas (84 high grade) were included. Two hundred and ninety regions of interest were analysed. Mean pixel brightness (MPB) and standard deviation (SD) were correlated with histological features. Close correlations were noted between MPB and cellularity, and SD and intrinsic cellular diversity.ConclusionsMPB and SD are objective measures reflecting the sensitivity of i3DUS in detecting the presence and extent of intrinsic brain tumours. They indirectly suggest heterogeneity, cellularity and invasiveness, providing information of the nature of the tumour, and also reflect the sensitivity of intraoperative US to detect the presence of residual intrinsic brain tumours. Development of this paradigm will enhance i3DUS use as an adjunct in brain tumour surgery. Optimizing its intraoperative application will impact surgical resection and, hence, patient outcome.

Two precedures are presented for image preprocessing, automated haze removal and the relative radiometric normalization of multitemporal optical images, to act as the data support for land cover change detection and image analysis. The developed algorithm for haze removal involves processes of feature and texture analysis of the multiresolution spatial frequency distribution of pixel brightness information content of a scene. The image contaminated by haze is decomposed into layers of different resolutions of spatial distribution frequencies. The radiometric characteristics of the corresponding layers are estimated and analyzed with topology based multiresolution spatial analysis technology. Based on the analysis, the haze component is then separated from the remaining spatial frequency components representing spectral information of actual land cover types in the scene, and a spectrally corrected image with “haze-off” characteristics is obtained. Then a method is used for radiometric normalization between multitemporal images of the same area. Case study using several different type images of Qingdao City in China proves the effectiveness of this technique except for those regions too hazy.

The 21-cm PDF (i.e., distribution of pixel brightness temperatures) is expected to be highly non-Gaussian during reionization and to provide important information on the distribution of density and ionization. We measure the 21-cm PDF as a function of redshift in a large simulation of cosmic reionization and propose a simple empirical fit. Guided by the simulated PDF, we then carry out a maximum likelihood analysis of the ability of upcoming experiments to measure the shape of the 21-cm PDF and derive from it the cosmic reionization history. Under the strongest assumptions, we find that upcoming experiments can measure the reionization history in the mid to late stages of reionization to 1-10% accuracy. Under a more flexible approach that allows for four free parameters at each redshift, a similar accuracy requires the lower noise levels of second-generation 21-cm experiments.

This paper describes a reliable method developed for a view-based navigation which uses approximate planes of image pixel brightness in which edge-based information has been modified with a least-square algorithm. The system developed in this work have shown not only the robustness of this method to ambient lighting conditions due to indoor illumination or daylight from windows, but also the high capability of its noise rejection for images taken in recording runs. This method has been found to be highly tolerated in larger ambient illumination change than the used conventional method where brightness-based pixel values are utilized. Based on this scheme, the experiment has been successfully made in the navigation test even if large ambient lighting condition was given to the robot by means of the change in the number of the luminescent lamps or in the night and the day.

A robust matching scheme for computing optical flow within a sequence of grayscale images is proposed. The technique employs the gradient information in textured images for extracting features in the form of orientation codes, which are then used for matching. The proposed method has been found to be robust in cases of matching under different ill-conditionings especially illumination variations. We utilize its robustness to compute optical flow in cases where illumination fluctuation is a problem and matching pixel brightness can introduce errors. Results of computation of optical flow field on real world scenes in the cases of translation, rotation and zooming have been presented and compared with other region matching techniques.

The ratio between water molecules associated to the clusters in cell structures, which is the conformational catalyst for the exchange processes, and non-associated or free water participating in free-radical reactions is very important for the normal functioning of the organs of living beings.The aim of the study was to compare Kirlian glow of apple samples before and after t h e sanctification during the Christian holiday The Saviour to detect the possibility of the bioavailability signs establishing of the product for the body.The kirlianographic study of 10 samples of whole and cut apples with the same sort and size before and after the sanctification was made. Radiographic film and standard methods of its development as well as the instrument “REK-1”, designed by Ukrainian Research Institute of Machine Building Technology (D nepropetrovsk) were used. Mathematical processing of scanned Kirlianograms was performed using standard software package for th e construction of histograms and pixel brightness profile of the picture.The method of classical kirlianography with X ray film allows assessing the bioavailability condition, which is important for the prediction of absorption and physiological effects of a man consumed food and phytomedicines. Therefore, these studies are relevant and require further development. Used such standard methods of mathematical processing as histograms and pixel brightness profile for the analysis of Kirlian images are informative enough for the individual samples, and can be the basis for the batch processing of data.

We present a new method of interpolation for the pixel brightness estimation in astronomical images. Our new method is simple and easily implementable. We show the comparison of this method with the widely used linear interpolation and other interpolation algorithms using one thousand astronomical images obtained from the Sloan Digital Sky Survey. The comparison shows that our method improves bad pixels brightness estimation with four times lower mean error than the presently most popular linear interpolation and has a better performance than any other examined method. The presented idea is flexible and can be also applied to presently used and future interpolation methods. The proposed method is especially useful for large sky surveys image reduction but can be also applied to single image correction., 16 pages, 10 figures. Printed in PASP, September 2013

The real time fire detection in video stream is one of the most interesting problems in computer vision. In fact, in most cases it would be nice to have fire detection algorithm implemented in usual industrial cameras and/or to have possibility to replace standard industrial cameras with one implementing the fire detection algorithm. In this paper, we present new algorithm for detecting fire in video. The algorithm is based on tracking suspicious regions in time with statistical analysis of their trajectory. False alarms are minimized by combining multiple detection criteria: pixel brightness, trajectories of suspicious regions for evaluating characteristic fire flickering and persistence of alarm state in sequence of frames. The resulting implementation is fast and therefore can run on wide range of affordable hardware. © The Authors, published by EDP Sciences, 2017.

Aneurismas da aorta tratados com endopróteses podem desenvolver endoleaks. Esses endoleaks devem ser classificados com base nos tipos de fluxo, além da localização anatômica. Enfatizamos tipos de fluxo dos endoleaks detectados pela ultrassonografia com Doppler: fluxo entra-e-sai como "pseudoaneurisma", fluxo de canal e fluxo direto. Ao se notar a possibilidade de endoleaks intermitentes, salientamos o conceito de endoseepage detectáveis por crescimento de dimensões sem fluxo entrante aparente. Sugerimos o uso da histologia virtual ultrassonográfica para detecção de infiltrações. Quantidade relativa e localização de sangue ou líquido dentro do saco aneurismático pode ser detectado pela avaliação dos níveis de brilho da ultrassonografia modo B. Essa informação permite um seguimento compreensivo do aneurisma tratado com endoprótese e salienta o risco maior deum endoleak de fluxo direto entrante no aneurisma. Aortic aneurysms treated with endovascular techniques may develop endoleaks. In addition to anatomic location, these endoleaks should be classified based on the type of blood flow. We describe the types of blood flow into the endoleaks as detected by Doppler ultrasonography: in-and-out flow as a "pseudoaneurysm", channel flow through the aneurysm, and direct flow into the aneurysm. Endoleaks may be intermittent and actually be endoseepage, detected by aneurysmal growth without an apparent inflow. Ultrasound virtual histology is suggested to detect endoseepage. Relative quantity and location of blood/liquid in the aneurysm can be detected by evaluating pixel brightness of the ultrasonographic B-mode image. Such anatomofunctional information allows for quantitative follow-up and emphasizes the risk of an endoleak with direct flow into the aneurysm.

In this study, a technique for analyzing directional wave spectra in shallow water areas using video image sequences is presented. The video image was obtained and collected by a single digital vid...

Minimum-relative-entropy method (MREM) has been presented as a solution to the missing short-baseline problem in the synthesis observations. It is shown that a measure of distance between the prior model and the image in the plane of pixel brightness is an adequate measure of relative entropy. The method has been further extended for polarization observations and the potential of the method against the conventional MEM has been demonstrated by simulated examples.

Rating ozone damage in common bean (Phaseolus vulgaris L.) requires visual estimation by experienced evaluators. The objective of this study was to determine whether an alternative digital method based on the mean and standard deviation of pixel brightness values from the video image of a leaf could rapidly and reliably measure ozone sensitivity of white bean breeding lines. Fourteen-day-old seedlings of 35 breeding lines and six parental cultivars were exposed to controlled fumigation with 0.20 μL L−1 ozone for 6 h during each of 4 d in growth chambers. On day 5, injury of the two unifoliolate leaves was evaluated using the digital method and visual estimates of damaged leaf area. The standard deviation of pixel brightness values was significantly correlated with the percentage damaged leaf area estimates (r = 0.68). The digital and visual methods identified most of the same breeding lines as ozone-insensitive, but disagreed on the ranking of the ozone-sensitive lines.Key words: Bean (common), Phaseolus vulgaris L., ozone, video image analysis, selection

Optical feedback driving schemes can enable accurate ageing and pixel brightness non-uniformity corrections in AMOLED displays. Here, we report on a pixel driver utilizing a metal-insulator-semiconductor (MIS) sensor for luminance control of the OLED element. In the proposed pixel architecture for bottom-emission AMOLEDs, the embedded MIS sensor shares the same layer stack with back-channel etched a-Si:H TFTs to maintain the fabrication simplicity. Performance characteristics of the MIS sensor are presented and analyzed to demonstrate its feasibility. Details on the pixel circuit functionality including the sensing and programming operations are also discussed.