background iodinated x-ray contrast media are the most commonly used contrast agents in the world with an annual application of 40-50 million. new non-ionic con- trast agents are subdivided into low osmolar agents such as iopromide and iso-osmolar agents such as iodixanol. regarding different biochemical characteristics, these agents are different in the allergic reactions and contrast enhancem...

 ABSTRACTBackground: Delivering the radiation dose to the target volume and minimizing the dose to normal tissues are the main objectives in radiotherapy. The aim of our study is to enhance the contrast of the portal image to increase the accuracy of delineation of the organs in the irradiation field.   Methods: The software was written based on local enhancement of the pixel values in image ma...

Purposes of Image Contrast Enhancement Enhancements are used to improve the appearance of an image and make it easier for visual interpretation, understanding, and analysis of imagery. There are a variety of point and local image enhancement operations. Point operations modify the DN of each pixel in an image independently, such as contrast stretching; Local operations modify the value of each ...

This article describes a dynamic contrast enhancement technique to improve the visual quality of low contrast images. Also, this proposed algorithm is recovered the images from a blurred and darkness specimen of the given area of the images, and get better quality of the images. In this article, Image enhancement is performed using evolutionary algorithm (i.e. Genetic Algorithm). Here, a specia...

This paper proposes a novel idea of reversible contrast enhancement (RCE) for digital images. Different from the traditional methods, we aim to embed the reversible feature into image contrast enhancement, making sure that the processed image can be losslessly turned back to the original. The original image is enhanced by histogram shrink and contrast stretching. Meanwhile, side information is ...

The contrast-enhanced magnetic resonance imaging (MRI) signal is rarely a direct measure of contrast concentration: rather it depends on the effect that the contrast agent has on the tissue water magnetization. To correctly interpret such studies, an understanding of the effects of water movement on the magnetic resonance (MR) signal is critical. In this review, we discuss how water difhion wit...

Histogram Equalization technique is one of the basic methods in image contrast enhancement. Using this method, in the case of images with uniform gray levels (with narrow histogram), causes loss of image detail and the natural look of the image. To overcome this problem and to have a better image contrast enhancement, a new two-step method was proposed. In the first step, the image histogram is...