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The sky regions of foggy image processed by all the existing conventional dehazing methods are degraded by color distortion and severe noise. This paper proposes an improved algorithm which combines dark channel prior and inverse image. We first invert the foggy image, and then estimate the transmission of the inverse image. At last, compared with the non-inversed transmission, the larger value...

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 ...

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 ...

Most of current camera calibration methods for a non-metric digital camera adopt polynomials of image coordinates composed of terms representing the correction to the principal distance, the offsets of the principal point, the radial lens distortion, and the decentering lens distortion of the target camera as the image distortion model. However, there is no standard procedure to evaluate approp...

Introduction:  Image  distortion  is  one  of  the  major  problems  of  magnetic  resonance  imaging  (MRI) for use in 3DMRI, velocity MRI, FMRI and radiotherapy treatment planning (RTTP). It is  widely known that the most obvious effect of the inhomogenity of the magnetic fields and the  nonlinearity  of  the  gradient  is  the  Geometric  Distortion  of  MR  tomograms.  In  this  study,  the...

Background: The magnetic resonance imaging (MRI)-based radiotherapy planning method have been considered in recent years because of the advantages of MRI and the problems of planning with two images modality. The first step in MRI-based radiotherapy is to evaluate magnetic resonance (MR) images geometric distortion. Therefore, the present study aimed to evaluate system related geometric distort...

We define the new idea of blind image repair as a process of correcting one or more different and unknown types of distortions afflicting an image. These distortions could introduce linear or non-linear degradations, compression artifacts, noise, etc., or combinations of these. Thus the concept encompasses denoising, deblurring, deblocking, deringing, and other post-acquisition image improvemen...