Discrete cosine transform (DCT) is a widely compression technique for converting an image into elementary frequency components. However, level of quality and compression is desired, scalar multiples of the JPEG standard quantization may be used. In this paper, DCT method was applied to compress image under various level of quality. Different quantization matrices of DCT’s coefficients are used ...

One of the most common positioning errors in panoramic radiography is the palatoglossal air space above the apices of the root of maxillary teeth. It causes a radiolucency obscuring the apices of maxillary teeth. In the case of this positioning error, the imaging should be repeated. This causes the patient to be exposed to radiation again. To avoid the repetition of exposing harmful X-rays to t...

sar (synthetic aperture radar) image enhancement and segmentation is purpose of this thesis. sar image segmentation is a primary step before steps such as classification and target recognition. the main obstacle in sar image segmentation is inherent speckle noise. speckle noise is a multiplicative and highly destructive noise which results to intensity inhomogeneity. hence common segmentation m...

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 ...

IntroductionA fine balance of image quality and radiation dose can be achieved by optimization to minimize stochastic and deterministic effects. This study aimed in ensuring that images of acceptable quality for common radiographic examinations in digital imaging were produced without causing harmful effects. Materials and MethodsThe study was conducted in three phases. The pre-optimization inv...

Radiographic image is the final product of imaging department and it passes through many steps before viewing. To achieve the ideal images with high quality and lowest possible radiation dose to the patient, one should take care during each stage of image formation which isn’t only practiced by one person who is designated to do that, It is the responsibility of everybody in the facility to imp...

Cancer stem cells (CSCs), defined by CD133 expression, harbor heterogeneous subpopulations of cells, including endothelial progenitor cells (EPCs). This study aimed to investigate whether a subpopulation of CSCs could affect the radiographic characteristics of glioblastoma. Tissue samples from 10 patients newly diagnosed with glioblastoma were selected according to the radiographic characterist...

With the advance of multimedia and diagnostic images technologies, the number of radiographic images is increasing constantly. The medical field demands sophisticated systems for search and retrieval of the produced multimedia document. This paper presents an ongoing research that focuses on the semantic content of radiographic image documents to facilitate semantic-based radiographic image ind...