Histogram equalization is an efficient contrast enhancement algorithm. Global equalization is effective, but enhances only overall contrast, while local histogram equalization is more powerful, but computationally expensive. In this paper, a Block-based Binomial Filtered Histogram Equalization (BBFHE) algorithm is presented. The image is divided into blocks, and for each block a histogram is ob...

A novel Image Inversion based Two Level Histogram Equalization (IIBLHE) for contrast enhancement is proposed in this paper. In this method, the first level of equalization is carried out in such a way that the image is inversed first and then histogram equalization is applied; again inversed and the second level of equalization is performed by modifying the probability density function of that ...

Contrast enhancement is an important factor in the image preprocessing step. One of the widely accepted contrast enhancement method is the histogram equalization. Although histogram equalization achieves comparatively better performance on almost all types of image, global histogram equalization sometimes produces excessive visual deterioration. A new extension of bi-histogram equalization call...

In this paper we consider transmission over channels which produce intersymbol interference. New equalization schemes derived from recently proposed lattice-reduction-aided equalization of multiple-input/ multiple-output channels are presented. The schemes exhibit low complexity, require no or only very little channel state information at the transmitter, and channel coding can be immediately a...

In multi-carrier code division multiple access (MCCDMA) uplink (mobile-to-base station), since different users’ signals go through different frequency-selective fading channels, large multi-access interference (MAI) is produced. The use of frequency-domain equalization reception can only partially restore the orthogonality among different users’ signals, resulting in a severe degradation in the...

Recently, space-time block coding has emerged as a promising spatial transmit diversity scheme, mainly due to its simple decoding complexity. As it was initially proposed, spacetime block coding was based on the assumption of flat multipath fading channel, where there is no intersymbol interference. In this paper, we investigate the performance of two different receiver proposals using space-ti...

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 brightness of the output image is significantly different from the input image. There are several extensions of histogram equalization has been proposed to overcome the brightness pre...

Abstract In multi carrier code division multiple access (MC-CDMA), since signals transmitted from different users go through different frequency-selective fading channels, the use of frequency-domain equalization at a receiver can only partially restore the orthogonality property among different users’ signals, resulting in the degraded bit error ratio (BER) performance due to large multi-acces...