with the development in the digital imaging techniques, an image enhancement is one of the characteristic of image. The medical image enhancement is one of the application, these data can be suffer from some of the unnecessary noise, lack of contrast, sharpening and distort images due to these flaws we obtain false report for diagnosis of diseases. So for improving the quality of the medical im...

Sharpening filters are used to highlight fine image details, including object edges. However, sharpening very specific different types of images as they may create undesired edge effects, over-highlight or emphasize noise. Laplacian, Laplacian Gaussian, high-boost, unsharp masking filters, and their extended algorithms among most widely spatial filters. This paper introduces a method that integ...

It is well-known that Gaussian filter is the most important model in image denoising. However, the inverse of the Gaussian model for image sharpening is seriously ill-posed. In this paper, we propose several variations of the Gaussian model, which are derived from the varied diffusion equations. Explicit forms for these models (filters) are given in the Fourier space, which facilitate the usage...

PURPOSE Contrast, sharpness, enhancement, and density can be changed in digital systems. The important question is to what extent the changes in these variables affect the accuracy of caries detection. MATERIALS AND METHODS Forty eight extracted human posterior teeth with healthy or proximal caries surfaces were imaged using a photostimulable phosphor (PSP) sensor. All original images were pr...

In this chapter, different approaches to image fusion for pan-sharpening of multispectral images are presented and critically compared. Particular emphasis is devoted to the advantages resulting from defining pan-sharpening as an optimisation problem. Implementation issues are also considered and extensive results in terms of quality of the fused products, both visual and objective, and computa...

A large-scale psychophysical experiment was performed examining the effects of various simultaneous variations of image parameters on perceived image sharpness. The goal of this experiment was to unlock some of the rules of image sharpness perception. A paired comparison paradigm was used to compare images of different resolution, contrast, noise, and sharpening. In total, 50 people performed o...

In order to simultaneously sharpen image details and attenuate noise, we propose to combine the recent blockmatching and 3D Þltering (BM3D) denoising approach, based on 3D transform-domain collaborative Þltering, with alpha-rooting, a transform-domain sharpening technique. The BM3D exploits grouping of similar image blocks into 3D arrays (groups) on which collaborative Þltering (by hard-thresho...

In this work, the bands of a Sentinel-2A image with spatial resolutions of 20 m and 60 m are sharpened to a spatial resolution of 10 m to obtain visible and near-infrared (VNIR) and shortwave infrared (SWIR) spectral bands with a spatial resolution of 10 m. In particular, we propose a two-step sharpening algorithm for Sentinel-2A imagery based on modified, selected, and synthesized band schemes...