Unified Approach to Image Distortion

Unified Approach to Image Distortion: D-U and U-D Models

We propose a unified view to deal with two formulations of image distortion and a method for estimating the distortion parameters for both of the formulations; So far the formulations have been developed separately. The proposed method is based on image registration and consists of nonlinear optimization to estimate parameters including view change and radial distortion. Experimental results de...

Image Retargeting by Combining Region Warping and Occlusion

Image retargeting aims to avoid visual distortion while retaining important image content in resizing. However, current image retargeting methods usually fail in difficult situations, such as complex structures and intricate arrangements of objects. In this paper, we propose a novel image retargeting approach, which provides low visual distortion retargeting results by combining region warping ...

Effect of Phase-Encoding Reduction on Geometric Distortion and BOLD Signal Changes in fMRI

Introduction Echo-planar imaging (EPI) is a group of fast data acquisition methods commonly used in fMRI studies. It acquires multiple image lines in k-space after a single excitation, which leads to a very short scan time. A well-known problem with EPI is that it is more sensitive to distortions due to the used encoding scheme. Source of distortion is inhomogeneity in the static B0 field that ...

Quantization with Lagrangian Distortion Measures

The Lagrangian formulations of fixedrate and variable-rate vector quantization can be combined into a single formulation involving constraints on both entropy and log codebook size. The approach leads to a Lloyd design algorithm and to results on high-rate or high-resolution quantization. It provides both a unified view of the traditional results and an approach to studying the implications of ...

A Novel Method for Measuring, Regardless of Image Distortion and Lens Varying Specifications in Endoscopic Treatment of Vesicoureteral Reflux