A method for sharpening of 3D volume images has been developed. The idea of the proposed algorithm is to transform the 3D neighborhood of the edge so that the neighboring pixels move closer to the edge, and then resample the image from the warped grid to the original pixel grid. The proposed technique preserves image textures while making the edges sharper. The effectiveness of the proposed met...

The paper presents a new edge width estimation method based on Gaussian edge model and unsharp mask analysis. The proposed method is accurate and robust to noise. Its effectiveness is demonstrated by its application for the problem of defocus map estimation from a single image. Sparse defocus map is constructed using edge detection algorithm followed by the proposed edge width estimation algori...

To study the meaningful range of settings for the parameters of interest, a standard psychophysical procedure, the “method of adjustment” was used [Gescheider 1997]. This was deemed to be the most appropriate choice for the current study since it allows both for an efficient implementation of the experiment and provides a single means of estimating all thresholds and preference values of interest.

We present a near-infrared Kn–band photometric study of edge–on galaxies with a box/peanut–shaped ‘bulge’. The morphology of the galaxies is analysed using unsharp masking and fits to the vertical surface brightness profiles, and the results are compared to N–body simulations and orbital calculations of barred galaxies. Both theoretical approaches reproduce the main structures observed.

This paper proposes a new method for automatic improvement in image quality through adjusting the image sharpness. This method does not need prior knowledge about image blur. To accomplish this work, the authors developed a new method for evaluating image sharpness without MTF. This is called image "edge sharpness* value. According to the subjective experiments, optimal edge sharpness value for...

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...

Contrast in photographic and computer-generated imagery communicates colour and lightness differences that would be perceived when viewing the represented scene. Due to depiction constraints, the amount of displayable contrast is limited, reducing the image’s ability to accurately represent the scene. A local contrast enhancement technique called unsharp masking can overcome these constraints b...

Enhancement of contrast and sharpness of an image is required in many applications. Unsharp masking is a classical tool for sharpness enhancement. We propose a generalized unsharp masking algorithm using the exploratory data model as a unified framework. The proposed algorithm is designed to address three issues: 1) simultaneously enhancing contrast and sharpness by means of individual treatmen...

We describe an automated edge enhancement procedure that operates in conjunction with clustereddot dithering, edge weighted unsharp masking, compound anisotropic diffusion etc. The goal is to make weak edges more noticeable and to give the strong edges in the half toned image a sharper and more natural appearance. Unsharp masking that is widely used for image enhancement amplifies image contras...