Traditional filtering methods operate on the entire signal or image. In some applications, however, errors are concentrated in specific regions or features. A prime example is images generated using computed tomography. Practical implementations limit the amount of high frequency content in the reconstructed image, and consequently, edges are blurred. We introduce a new post-reconstruction edge...

We introduce a family of first-order multi-dimensional ordinary differential equations (ODEs) with discontinuous right-hand sides and demonstrate their applicability in image processing. An equation belonging to this family is an inverse diffusion everywhere except at local extrema, where some stabilization is introduced. For this reason, we call these equations “stabilized inverse diffusion eq...

Traditional multispectral classification based road extraction methods separate roads from other ground features according to spectral characteristics of individual pixels. To take use of the spatial properties of high-resolution satellite images, in this paper we integrate spectral information from the multispectral (MS) image with spatial information from the panchromatic (Pan) image for road...

Comb filters are a class of low-complexity filters especially useful for multistage decimation processes. However, the magnitude response of comb filters presents a droop in the passband region and low stopband attenuation, which is undesirable in many applications. In this work, it is shown that, for stringent magnitude specifications, sharpening compensated comb filters requires a lower-degre...

Contrast-sharpening is a fundamental feature of mammalian sensory perception. Whereas visual contrast-sharpening has been fully understood in terms of the retinal neuronal wiring [DeVries, S. H. & Baylor, D. A. (1993) Cell 72, Suppl., 139-149], a corresponding explanation of auditory contrast-sharpening is still lacking. Here, we show that the essentials of auditory contrast-sharpening can be e...

The problem of removing blur from, or sharpening, astronomical star field intensity images is discussed. An approach to image restoration that recovers image detail using a constrained optimization theoretic approach is introduced. Ideal star images may be modeled as a few point sources in a uniform background. It is argued that a direct measure of image sparseness is the appropriate optimizati...

Efficient enhancement of noisy optical coherence tomography (OCT) images is a key task for interpreting them correctly. In this paper, to better enhance details and layered structures of a human retina image, we propose a collaborative shock filtering for OCT image denoising and enhancement. Noisy OCT image is first denoised by a collaborative filtering method with new similarity measure, and t...

Nuclear medicine (NM) images inherently suffer from large amounts of noise and blur. The purpose of this research is to reduce the noise and blur while maintaining image integrity for improved diagnosis. The proposed solution is to increase image quality after the standard preand postprocessing undertaken by a gamma camera system. Mean Field Annealing (MFA) is the image processing technique use...

An interactive system for designing curved surfaces is proposed which is based on direct manipulation of a single-view shaded image of this surface. Apart from functions like carving in the surface or adding to it, and local smoothing, sharpening or shifting of selected surface regions, the system supports painting local gradient distributions. An iterative algorithm enforces conservativity of ...

A common observation about confocal microscopy images is that lower image stacks have lower voxel intensities and are usually blurred in comparison with the upper ones. The key reasons are light absorption and scattering by the objects and particles in the volume through which light passes. This report proposes a new technique to reduce such noise impacts in terms of an adaptive intensity compe...