this paper presents a modified digital image watermarking method based on nonnegative matrix factorization. firstly, host image is factorized to the product of three nonnegative matrices. then, the centric matrix is transferred to discrete cosine transform domain. watermark is embedded in low frequency band of this matrix and next, the reverse of the transform is computed. finally, watermarked ...

introduction: tracking temporal changes of temperature during laser skin treatment plays an important role in improving the process of laser skin treatment itself. there are a number of methods to analyze temperature’s temporal dependency during laser skin treatment; some of those methods depend on imaging the skin with thermal cameras. however, the use of thermal cameras exhibits specific prob...

Introdouction: The mapping of ghost images of the maxilla and the nasal cavity, which are complex structures, is very important. The position of objects that create a ghost image can differ when using various devices. The purpose of this investigation was to study the mapping of ghost images of the maxilla and the nasal cavity using a Cranex D digital panoramic machine. Materials and methods: ...

introdouction: the mapping of ghost images of the maxilla and the nasal cavity, which are complex structures, is very important. the position of objects that create a ghost image can differ when using various devices. the purpose of this investigation was to study the mapping of ghost images of the maxilla and the nasal cavity using a cranex d digital panoramic machine. materials and methods: t...

objective: after introduction of digital radiography into dentistry several methods of image acquisition were accessible in the field of dentistry. in many instances it is necessary to digitize analog images. there is no overall acceptable method for image digitization so all different types of images can be comparable. the objective of this study was to compare the diagnostic accuracy of diffe...

background:   fl uence of image compression on the identi fi   materials and methods:   fi   fi   fi   results:   conclusion:   fi   fi   le format for the compression of digital lateral cephalograms. cation of cephalometric points compared with the dicom format. jpeg2000 is a reliable   jpeg2000 images of lateral cephalograms with quality factors 85, 75, and 60 did not demonstrate any alterati...

background the first commercial system for digital radiography was introduced in 1987, and it has evolved a great deal since then. currently, it is possible to enhance images in digital radiography. objectives the aim of this study is to evaluate the diagnostic accuracy of image enhancement in direct digital radiography as it relates to interproximal carries assessment. conclusions using these ...

Background & Aims: Teleradiology as an efficient way for avoiding unnecessary transfer of patients to special medical centers requires the images with digital format. However, in some developing countries, including Iran, imaging is being done using non digital devices. In such cases, changing analog images into digital ones can solve the problem. The method which is nowadays used for digita...