This paper presents a method for lane boundaries detection which is not affected by the shadows, illumination and un- even road conditions. This method is based upon processing grayscale images using local gradient features, characteris- tic spectrum of lanes, and linear prediction. Firstly, points on the adjacent right and left lane are recognized using the local gradient descriptors. A simple linear prediction model is deployed to predict the direction of lane markers. The contribution of this paper is the use of vertical gradient image without converting into binary image(using suitable thre- shold), and introduction of characteristic lane gradient spectrum within the local window to locate the preciselane marking points along the horizontal scan line over the image. Experimental results show that this method has greater tolerance to shadows and low illumination conditions. A comparison is drawn between this method and recent methods reported in the literature.
Homomorphic filter is an algorithm to enhance image contrast and compress brightness range. In order to eliminate the effect of low illumination, we can reduce the low frequency and increase the high frequency, so as to highlight the details of the image . Obstacles image can be represented as Lambertian-reflectance model. The equation is:
Inspired by dark channel prior, a new image prior, bright channel prior, is proposed to estimate local exposure for under exposed images in  and , respectively. A similar method was also employed in , where they esti- mate the illumination of an input image using a two-stage map method; the illumination of each pixel is first esti- mated individually by finding the maximum value in R, G, and B channels. Further, refine the initial illumination map by imposing a structure prior on it as the final illumina- tion map. Having the well-constructed illumination map, the enhancement can be achieved accordingly. Although this kind of methods is effective for very low illumination image, they are sensitive to bright light. If there is light object in the low illumination image or bright objects, the method might fail to obtain good enhancement.
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According to the environmental illumination at night, we divide the traffic scene into sufficient lighting and low illumination two cases. This article mainly aims in low illumination environment during the night. Retinex theory  is adopted to improve the low illumination image enhancement. Different from the traditional linear and nonlinear method that can only enhance one kind of image characteristics, Retinex can in dynamic range compression, edge enhancement, and color constancy three aspects equilibrium, so a variety of different types of images can be adaptive enhancement. In this paper, on the basis of single scale Retinex SSR (Single Scale Retinex) we use multi-scale Retinex MSR （Multi Scale Retinex）to process image enhancement . MSR is developed on the basis of SSR, its advantage is can keep image high fidelity and dynamic range of image compression at the same time, and in some cases, MSR can realize color enhancement, color constancy, the local dynamic range compression, and the global dynamic range compression, it can also be used in X-ray image enhancement. Formula (1) (2) as follows:
The result is a binary segmentation of the image, which highlights regions of non-stationary objects. The simplest form of the reference image is a time-averaged background image. This method suffers from many problems and requires a training period absent of foreground objects. The motion of background objects after the training period and foreground objects motionless during the training period would be considered as permanent foreground objects. In addition, the approach cannot cope with gradual illumination changes in the scene.
automatically control takes action over DIMMING. (i.e., low illumination, acts as supporting feature for natural light). Now, ZigBee device (at transmission side) is ready to receive information from streetlight and communicate with ZigBee device (at receiver side), then sends to terminal via serial communication cable. ZigBee device communicates point-to-point to detect the vehicle and sunlight in the system. So that the system can receive data from android phone ,upon receiving the data the micro control unit gives appropriate signals to the driver circuits of the appliances so that the appliances can be switched on and off.
Low daily illumination was weakly associated with depressed mood. Hispanic women experienced lower illu- mination, but in ANCOVA models, controlling for illumi- nation eliminated only 12% of the variance in depression attributable to ethnicity. It is plausible that low illumina- tion was a source of depressed mood, but the converse would also be plausible. That is, depression might influ- ence women to spend less time outdoors in daylight. The more substantial correlation of illumination with the glo- bal assessment of functioning may be consistent with the hypothesis that poor functioning causes poor illumina- tion experience which then may contribute to depression, perhaps engendering a circular process. Low illumination experience might also be a contributing cause to the poor global function with which it was associated. It is plausi- ble that income directly affects global function, as func- tional ability no doubt affects income, but income may also influence global functioning indirectly through illu- mination experience, e.g., a wealthy woman with a home garden and a golf club membership might experience more daylight than a woman of modest means living in an apartment.
Abstract-The MSR algorithms, for the most part, have defined weights in spite of image properties. So it generates the genuine artifact, less clear image. Most of the dehazing strategy use retinex algorithm. We proposed an algorithm that adopts the nonillumination and protects edges to estimate the clarity of the image. Here the optimal weights are adopted based on the level of haze in the image. Gradually the image artifacts are diminished more by expanding color constancy, local dynamic range by adjusting the local contrast adaptively depending on the depth of image details. So images under variable illumination conditions such as lightness and sensitive to distortion created by cameras produce a photo in dim light are considered as input to our proposed method. MSRCR can achieve the picture color constancy, neighborhood range of pixel, compression, color enhancement good under all above circumstances. But the enhancement is improved by fusing Bilateral histogram equalization method as a pre-preocessing and MSRCR is used as ppst processing. In this paper, various quality metrics are calculated among the contrast enhancement and fusion retinex processed images taken under low illumination effect with a different cell phone
a sign reversal from positive to negative values. Below and above the illumination time t ≈ 28 s, the majority charge carrier switches from electrons to holes. (b) Hall resistance versus the magnetic field, measured for the illumination times indicated in the vertical lines and corresponding numbers from panel (a). The Hall resistance traces are color coded. In the electron regime, corresponding to low illumination times, the Hall resistance curves show well pronounced integer quantum Hall plateaus. In the hole regime, corresponding to high illumination times, the Hall resistance shows distinct two-carrier transport with a sign reversal of the Hall resistance at about B = 0.5 T.
Abstract: Complex illumination condition is one of the most critical challenging problems for practical face recognition. In this paper, we propose a novel method to improve the illumination invariants for solving this chal- lenge. Firstly, a new method based on the Lambert reflectance model is proposed to extract illumination invariant, which is less insensitive to complex illumination variations. Secondly, in order to repair the defects caused by process of illumination invariants extraction, Fast Mean Filter is utilized to smooth and remove noise. Lastly, for raising the richness of information in output image, a nonlinear normalization transformation is proposed. Com- pared with the state-of-the-arts, experimental results show that the proposed method can extract more robust illu- mination invariants. Apart from it, the richness of information in processed image is greater and superior perfor- mance in face recognition rate is superior.
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The decompose similar image sequences of outdoor scenes into a shadow mask and images illuminated only by skylight or sunlight. The image capturing an environment map at multiple times of the day. The image estimates the reflectance field of an outdoor scene that can then be used for relighting. These methods assume a fixed viewpoint and varying illumination while this method relies on images captured under different viewpoints and fixed illumination.
However, there is evidence suggesting that this ability, as in humans, is approximate rather than perfect. Data from previous experiments showed that larger changes in the illuminant caused the bees to make more mistakes when recognising coloured stimuli (Dyer, 1999; Neumeyer, 1981). Furthermore, if bees adapted flawlessly to changed illumination, they might not detect changes in the spectral content of illuminant light and would therefore not be able to use illumination information to influence their behaviour. However, it has been demonstrated that bees directly perceive changes in illuminating light (Dyer and Chittka, 2004b; Dyer, 2006). Additionally, bees can use the illumination as a contextual cue in foraging tasks (Lotto and Chittka, 2005). Further studies (Dyer, 1998; Dyer, 1999) used data on bees’ photoreceptor responses and the reflectance spectra of natural flowers to predict that some flowers would appear to change in colour to bees’ eyes under altered lighting, indicating that bees’ colour constancy might only be approximate. However, none of these experiments addressed the responses of bees to short-term changes in illumination that are associated with foraging in patchy light, as they might be encountered in nature, e.g. when moving rapidly into and out of illumination patches, the illumination surrounding the bee changes over seconds rather than minutes.
Second, for the speed of imaging, the instrumental limitations are the repetition rate of the ultrafast pulse train, the frame rate of the camera, and the translation rate of fiber bundle – if translation is required for homogeneous illumination (translation is not absolutely necessary for fiber bundles made of closely spaced, low numerical-aperture fibers). To date, commercially available ultrafast oscillators can provide repetition rates up to 1-10 GHz at average powers of over a Watt, while if larger single pulse energies are needed, regenerative amplifiers can produce ≥mJ pulses with repetition rates into the many tens of kHz. Scientific-grade CMOS cameras already exceed rates of 1,000 fps with limited numbers (∼100-by-100) of pixels, and further advances in frame rate and image size can be expected. For fiber-bundle translation, fast mechanical stages typically achieve step rates of ∼1 kHz; for even faster operation, galvanometric mirrors that translate the foci at rates higher than 50 kHz can be used, in an optical design similar to a previously demonstrated multifocal system . Thus, the imaging speed of our technique can be pushed well beyond 1,000 fps even with the limits of currently available equipment and techniques.
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structures. When a crystalline structure is present, the electromagnetic radiation upon entering a material will be refracted to some degree by each individual crystal, which often leads to it hitting another portion of the material’s crystalline structure and being refracted again at another angle. This keeps occuring until the radiation finally is redirected back out of the object at a fairly random angle. Some absorption may also occur during this process. Thus, crystalline structures largely contribute to the degree of diffuse reflection that occurs in a material. For those familiar with polymers this should be fairly logicial. Highly transparent polymers generally have amourphous structures, but opague polymers have at least semicrystalline structures. Of course there are other factors that play a role in deciding whether an object/coating manages to reflect radiation or allows it to be transmitted, such as an object’s thickness, extinction coefficeints, and the wavelength of the electromagnetic radiation hitting the surface. The extra complexity can be illsutrated by the ability of extemely thin metals, such as those used in glass coatings being transmissive to visible, but reflective to thermal radiation. Whereas metals at more common thicknesses would typically reflect both. Thus, the key takeaway from this discussion is the understanding that specular and diffuse reflection have various implications on the design of low emissivty coatings. Their importance being largely assured by the type of reflection partially dictating the amount of thermal radiation a surface shows an imager.
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Where L and R are the captured image and the desired recovery, respectively and T represents the illumination map, and the operator ◦ means element wise multiplication. Here we consider that, for color images, three channels share the same illumination map. With slight difference in notations, we use T (ˆ T) to indicate one-channel and three-channel illumination maps interchangeably. From the above model(1) , say the observed image can be decomposed into the product of the desired light-enhanced scene and the illumination map. This model is related to the intrinsic image decomposition, which perform the decomposition of the input into two components. The main aim of the intrinsic image decomposition is to estimate the reflectance component and the shading one from the the image. By estimating the only reflectance component it loses the the shape of the image, which does not satisfy the purpose of low light image enhancement. For that reason in our proposed method we consider the illumination map which in turn recalls the visual content of the dark regions. From eq(1) R=L/T, where the division is element-wise. The estimated is the key to the recovery of R. By estimation of T the problem is solved. We have to
required dimensions of the field of light distributed by the laryngoscope. The ISO Standard 7376:2009 is in the process of Background: Direct laryngoscopy and successful endotracheal intubation require optimal illumination of laryngeal structures. The International Organization of Standardization (ISO) describes minimum adequate laryngoscope illuminance as 500 lux after 10 minutes, and further describes optimal dimensions of the illumination field. Laryngoscope light is subjectively assessed by the anaesthetist as part of theatre preparation. This study sought to describe the illumination of laryngoscopes at two academic hospitals, to compare illumination of incandescent and fibreoptic laryngoscopes and to compare the accuracy of a mobile phone application (app) to a lux meter.
First of all, we investigate the performances under different image resolutions. Figure 3 shows the aver- age recognition rate over the remaining subsets. Re- sults reveal that the proposed KLRC-p and KLRC-g outperform the other methods consistently. Low- resolution face images with 8 × 8 pixels degrade the performances significantly. Nonetheless, the proposed KLRC algorithms still could perform well under the very low-resolution condition. Also, the results show that the performances achieved by the PCA-based, LDA-based, and the other subspace projection methods are drastically reduced for resolution below 16 × 16 pixels. Moreover, it is interesting to point out that the KLRC-p and KLRC-q under 8 × 8 pixels out- perform the PCA-based and LDA-based approaches under 32 × 32 pixels significantly and achieve compar- able recognition rate by the LRC-based approaches under 32 × 32 pixels. LBP  is a local feature method which can effectively defense the illumination variations under 32 × 32 pixels. However, LBP cannot perform very well under very low-resolution situation
Abstract. Let f (x) be a diﬀerentiable function on the real line R, and let P be a point not on the graph of f (x). Deﬁne the illumination index of P to be the number of distinct tangents to the graph of f which pass through P. We prove that if f is continuous and nonnegative on R, f ≥ m > 0 outside a closed interval of R, and f has ﬁnitely many zeros on R , then any point P below the graph of f has illumination index 2. This result fails in general if f is not bounded away from 0 on R . Also, if f has ﬁnitely many zeros and f is not nonnegative on R , then some point below the graph has illumination index not equal to 2. Finally, we generalize our results to illumination by odd order Taylor polynomials. 2000 Mathematics Subject Classiﬁcation. 26A06.
3. FUZZY HOMOMORPHIC IMAGE ENHANCEMENT FUZZY HOMOMORPHIC IMAGE ENHANCEMENT FUZZY HOMOMORPHIC IMAGE ENHANCEMENT FUZZY HOMOMORPHIC IMAGE ENHANCEMENT After the conversion of the multiplicative nature of the illumination and reflectance component of an image to a linear, additive form, it is easy to transform the log image into the fuzzy domain using a suitable membership function. In Figure 2, a Fourier transformation of the logarithm-transformed image is performed to aid in the visualization of high and low frequency regions of the image. The linearization effect of the logarithm operator is observed, with regards to the image
area between two electrodes (connected through bottom LNO electrode) was fabricated to probe the polarization. P-V loops were symmetrical and saturated, and almost frequency independent below 10 Hz probe frequency as can be seen from Fig. 4(a). A significant enhancement (nearly 100%) in ferroelectric polarization and displacement current were observed under illumination of monochromatic light for DC configuration, whereas a small change (nearly 15 %) under illumination in ferroelectric polarization (at 50 Hz) were observed in the case of SC configuration. It indicates that a large amount of optically active charge carriers contribute significantly for DC connected in series (due to the large active area) rather than SC configuration under illumination. We have done polarization and PUND analysis for various frequencies and pulse widths. The presented data is the best data where the film shows a maximum change in polarization under illumination of light. The enhancement in polarization under illumination of thin film heterostructure by an energy source may be due to the effective contribution of electronic polarization and orientation of ionic polarization in the direction of applied electric field. Matthew Dawber et. al. suggested that change in the spatial distribution of 2p electron orbitals of oxygen ions in perovskite octahedral may lead to the development of
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