BACKGROUND Intensity normalization is an important preprocessing step in brain magnetic resonance image (MRI) analysis. During MR image acquisition, different scanners or parameters would be used for scanning different subjects or the same subject at a different time, which may result in large intensity variations. This intensity variation will greatly undermine the performance of subsequent MR...

The segmentation in medical images especially in the field of MR image is a challenging task in the presence of intensity inhomogenity. So many techniques have been devised to correct this artifact. The intensity inhomogenity also known as intensity non uniformity refers to the slow, non atomic intensity variations of the same tissue over the image domain. This paper attempts to review some of ...

A two-step elastic medical image registration approach is proposed, which is based on the image intensity. In the first step, the global affine medical image registration is used to establish one-to-one mapping between the two images to be registered. After this first step, the images are registered up to small local elastic deformation. Then the mapped images are used as inputs in the second s...

A method lor the determination of lightness from image intensity is presented. For certain classes ot images, lightness corresponds to reflectance, while image intensity is the product of reflectance and illumination intensity. The method is two-dimensional and depends on the different spatial distribution of these two components of image intensity. Such a lightness-judging process is required ...

In this paper, we propose a new method for 3D-2D registration based on SIFT and a range intensity image, which is a kind of intensity image simultaneously acquired with a range image using an active range sensor. A linear equation for the registration parameters is formulated, which is combined with displacement estimations for extrinsic and intrinsic parameters and the distortion of a camera’s...

In Three-dimensional (3-D) image measurement field, pattern projection measurement methods based on the image intensity analysis are expected, because those can detect more numbers of stripes order by single projection. However, in the case when the intensity difference between stripes is narrow, the detecting of stripes order becomes difficult.In order to improve the detection accuracy of stri...

this paper represents a new region-based active contour model that can be used to segment images with intensity non-uniformity and high level noise. the main idea of our proposed method is to use gaussian distributions with different means and variances with incorporation of intensity non-uniformity model for image segmentation. in order to integrate the spatial information between neighboring ...

The present paper is aimed at introducing a new algorithm for image encryption using chaotic tent maps and the desired key image. This algorithm consists of two parts, the first of which works in the frequency domain and the second, in the time domain. In the frequency domain, a desired key image is used, and a random number is generated, using the chaotic tent map, in order to change the phase...

Active contour models are very popular in image segmentation. Different features such as mean gray and variance are selected for different purpose. But for image with intensity inhomogeneities, there are no features for segmentation using the active contour model. The images with intensity inhomogeneities often occurred in real world especially in medical images. To deal with the difficulties r...