Histogram equalization (HE) is widely used for contrast enhancement. However, it tends to change the brightness of an image and hence, not suitable for consumer electronic products, where preserving the original brightness is essential to avoid annoying artifacts. Bi-histogram equalization (BBHE) has been proposed and analyzed mathematically that it can preserve the original brightness to a cer...

In this paper we investigate two approaches to content based image retrieval and their application to near duplicate detection in image collections. The first approach was proposed by C.E. Jacobs et al. [10]. It involves wavelet transformation of source image to extract features. The second approach is based on so called matrix of brightness variations which uses signs of partial derivatives of...

Traditional methods for computing optical flow are mainly based on image brightness constancy. In the real world the brightness constancy usually does not hold. Here we present the idea of using invariant feature based on the brightness change model to estimate the optical flow. Both the mathematical derivation and the experiments show that the new model is better than brightness based optical ...

Image brightness is generally desirable to be uniform except regions where it changes to form an image. There are factors, however, that tend to produce variation in the brightness of a displayed image even when no image detail is present. This variation is usually random and has no particular pattern. In many cases, it reduces image quality. This random variation in image brightness is designa...

The goal of image enhancement technique is to improve a characteristics or quality of an image, such that the resulting image is better than the original image. Histogram equalization (HE) is widely used for contrast enhancement. However, it tends to change the brightness of an images, where preserving the original brightness is essential to avoid annoying artifacts. So Bi-histogram equalizatio...

A new technique, Bi-Level Weighted Histogram Equalization (BWHE) is proposed in this paper for the purpose of better brightness preservation and contrast enhancement of any input image. This technique applies bi-level weighting procedure on Brightness preserving Bi-Histogram Equalization (BBHE) to enhance the input images. The core idea of this method is to first segment the histogram of the in...

chest radiography is a common diagnostic imaging test, which contains an enormous amount of information about a patient. however,its interpretation is highly challenging. the accuracy of the diagnostic process is greatly influenced by image processing algorithms;hence enhancement of the images is indispensable in order to improve visibility of the details. this paper aims at improving radiograp...

The paper computes the reliability of estimates of image motion parameters. The use of such measures of reliability to weight motion estimates improves significantly the performance of motion analysis tasks such as the recovery of 3D structure [1, 2]. The paper relates both the estimation error variance and the stability of the estimation algorithm with the spatial gradient of the image brightn...

A histogram is a graphical representation of the distribution of data in an image. It is an estimate of the probability distribution of a continuous variable (quantitative variable). Histogram Equalization is a contrast enhancement technique in the image processing which uses the histogram of image. However histogram equalization is not the best method for contrast enhancement because the mean ...

In this paper, an effective image demosaicking algorithm, which is based on the correlation among the three primary colors, is proposed for mosaic image with Bayer color filter array (CFA). To reduce the distortion and improve the reconstruction quality, the proposed interpolation method makes full use of the brightness information and the edge information. We design several filters with size o...