This paper presents a novel algorithm for a color image encryption which involves simultaneously two operations in one: permutation and substitution of pixels. It uses the rows and columns of images’ bits as transformation units. Each bit is regarded as an observed entity having a light ray which intersects a new rotated image. The intersection position is used to paste the corresponding bit. S...

Image segmentation is a fundamental approach in the field of image processing and based on user’s application .This paper propose an original and simple segmentation strategy based on the EM approach that resolves many informatics problems about hyperspectral images which are observed by airborne sensors. In a first step, to simplify the input color textured image into a color image without tex...

This paper presents the compression mechanism based on the fractal coding and spiral architecture for the color image data of multimedia applications or system. This compression mechanism can be used prior to the encryption in multimedia system security mechanism. Proposed mechanism falls in lossy compression category. Basically, the fractal coding is applied on the grey level images and encodi...

In digital color imaging, it is of interest to transform the color scene of an image to the other. Some attempts have been done in this case using, for example, lαβ color space, principal component analysis and recently histogram rescaling method. In this research, a novel method is proposed based on the Resenfeld and Kak histogram matching algorithm. It is suggested that to transform the color...

localizing the optic disc (od) in retinal fundus images is of critical importance, since it is very similar to hard exudates (found in pathology) in color and brightness. because of the importance of od localization in clinical applications, many techniques have been developed. in this paper, we present the results obtained from two methods, correlation and least square, to approximate the opti...

The chaos-based image cryptosystems have been widely investigated in recent years to provide real-time encryption and transmission. In this paper, a novel color image encryption algorithm by using coupled-map lattices (CML) and a fractional-order chaotic system is proposed to enhance the security and robustness of the encryption algorithms with a permutation-diffusion structure. To make the enc...

Cryptography is one of the most important security mechanisms for transmission digital media on Internet. Most proposed cryptographic image methods based chaotic maps are dependent upon sizes and them worked square images. In this paper tackling problem, a scale-invariant color encryption method in three-dimensional space presented. At first, two-dimensional converted into space, case, red, gre...