Partial Differential Equations (PDEs) have become an important tool in image processing and analysis. A PDE mode for image zooming is introduced in this paper. This model exploits a higher order nonlinear partial differential equation. The resulted nonlinear equation is solved by an explicit finite difference schemes. Numerical results on real digital images are given to show effectiveness and ...

We propose a navigation technique for browsing large documents that integrates rate-based scrolling with automatic zooming. The view automatically zooms out when the user scrolls rapidly so that the perceptual scrolling speed in screen space remains constant. As a result, the user can efficiently and smoothly navigate through a large document without becoming disoriented by extremely fast visua...

This note reports the main research results of the Imaging and Graphic Research Group in the field of image analysis and enhancement. Particular emphasis, reporting also some major details, is given to methods and techniques devoted to unsupervised image analysis and classification, automatic text discrimination, adaptive interpolation and zooming, color and contrast enhancement.

E-splines (Exponential spline) polynomials represent the best smooth transition between continuous and discrete domains. As they are constructed from convolution of exponential segments, there are many degrees of freedom to optimally choose the most convenient E-spline, suitable for a specific application. In this paper, the parameters of these E-splines were optimally chosen, to enhance the pe...

The image grand tour (IGT) is a method for visualizing multi– spectral images or multiple registered images. The IGT projects a linear combination of the pixel vectors into one– dimensional space (for each pixel) and renders these projected values as a gray–scale image. We will present a JAVA–based version of the IGT with additional software enhancements such as the capability of zooming into a...

Abstract This is a digest of the work and research completed thus far in developing a progressive image transmission scheme. Efficient and quick communication of perceptually important image information is desired resulting in this research with wavelet and fractal techniques for the identification and extraction of perceptually important features. This is done with the final goal of interactiv...

Photomosaic arranges many small photographs to represent a large image. Our study applies the photomosaic to a photograph browser CAT. Our implementation displays photomosaic while zooming out, and individual photographs while zooming in. Here, many photograph browsing software displays a set of photographs in the order of their times. To maintain this order of photographs, our photomosaic-like...

We present a novel technique for calibrating a zooming camera based on the invariance properties of the Normalized Image of the Absolute Conic (NIAC). First, we show that the camera parameters (independent of the position, orientation and zooming) are determined uniquely by the NIAC. Then, we exploit the invariance properties to develop a stratified calibration method that decouples the calibra...

Many image processing applications require estimating the orientation of the image edges. This estimation is often done with a finite difference approximation of the orthogonal gradient. As an alternative, we apply contour stencils, a method for detecting contours from total variation along curves, and show it more robustly estimates the edge orientations than several finite difference approxim...