A quick and accurate way to rotate and shift nuclear magnetic resonance (NMR) images using the two-dimensional chirp-z transform is presented. When the desired image grid is rotated and shifted from the original grid due to patient motion, the chirp-z transform can reconstruct NMR images directly onto the ultimate grid instead of reconstructing onto the original grid and then applying interpola...

Interpolation is a fundamental issue in image processing. In this short paper, we communicate ongoing results concerning the accuracy of two landmark approaches: the Shannon expansion and the Discrete Fourier Transform (DFT) interpolation. Among all sources of error, we focus on the impact of spatial truncation. Our estimations are expressed in the form of upper bounds on the Root Mean Squared ...

In this paperwepresent a local interpolation-based variant of the well-known polar format algorithm used for synthetic aperture radar (SAR) image formation.We develop the algorithm to match the capabilities of the applicationspecific logic-in-memory processing paradigm, which offloads lightweight computation directly into the SRAM and DRAM. Our proposed algorithm performs filtering, an image pe...

In this paper we describe a novel general purpose image interpolation method based on the combination of two different procedures. First, an adaptive algorithm is applied interpolating locally pixel values along the direction where second order image derivative is lower. Then interpolated values are modified using an iterative refinement minimizing differences in second order image derivatives,...

This paper presents some image processing techniques that can be used for radiographic image enhancement. Contrast enhancement, filtering, denoising, and interpolation processes are carried out in this paper. Contrast enhancement is carried out using adaptive histogram equalization. Filtering is carried out using median, Wiener, Lee, and Kuan filters. Wavelet and curvelet transforms are used fo...

Image warping is a popular tool for smoothly transforming one image to another. \Morphing" techniques based on geometric image interpolation create compelling visual e ects, but the validity of such transformations has not been established. In particular, does 2D interpolation of two views of the same scene produce a sequence of physically valid in-between views of that scene? In this paper, we...

World has entered in 21 century. The technology of computer graphics and digital cameras is prevalent. High resolution display and printer are available. Therefore high resolution images are needed in order to produce high quality display images and high quality prints. However, since high resolution images are not usually provided, there is a need to magnify the original images. One common dif...

Aim: To assess whether retinal vascular caliber measurement from digital fundus photographs using IVAN software (University of Wisconsin, Madison, WI) is affected by bicubic image interpolation using image processing software (Photoshop version 5.5, Adobe Systems Inc., San Jose, CA). Material and methods: 32 good quality optic disc centered retina photos (slides) acquired in healthy volunteers ...

Triangulation is a good tool for vector representation of raster image data. To visualize the image represented by triangulation, one needs to fit a continuous surface of colour intensity in the triangulation, i.e. to interpolate data stored in its vertices. This paper presents some interpolation methods for the purpose of use on digital images and compares them. The commonly used piecewise lin...