Background Irregularly irregular arrhythmia is difficult to image with conventional cine CMR because arrhythmia rejection and registration-based reconstruction result in cardiac motion artifacts or unachievable breath-hold durations. Undersampled radial trajectories, combined with a suitable non-Cartesian reconstruction algorithm, have the potential to overcome these problems by sampling a smal...

It is well-known that Total Variation (TV) minimization with L data fidelity terms (which corresponds to white Gaussian additive noise) yields a restored image which presents some loss of contrast. The same behavior occurs for TVmodels with non-convex data fidelity terms that represent speckle noise. In this note we propose a new approach to cope with the restoration of Synthetic Aperture Radar...

Nuclear medicine imaging systems rely on photon detection as the basis of image formation. One of the major sources of error in these imaging systems is Poisson noise. In this paper, we develop a novel multiscale image restoration procedure for photon imaging systems. It consists in separating in the wavelet-domain data points which belong to structures from those due to the noisy background. T...

This paper presents the results of two computational experiments designed to investigate whether the success of recent image fidelity metrics can be attributed to the fact that these metrics implicitly incorporate region-of-interest information. Modified versions of four metrics (PSNR, WSNR, SSIM, and VIF) were created by incorporating spatially varying weights chosen to maximize correlation be...

In this paper a 4 x 4 Daubechies transform based authentication technique termed as SADT has been proposed to authenticate gray scale images. The cover image is transformed into the frequency domain using 4 x 4 mask in a row major order using Daubechies transform technique, resulting four frequency subbands AF, HF, VF and DF. One byte of every band in a mask is embedding with two/four bits of s...

We propose a novel image contrast enhancement method via non-convex gradient fidelity-based (NGF) variational model which consists of the data fidelity term and the NGF regularization. The NGF prior assumes that the gradient of the desired image is close to the multiplication of the gradient of the original image by a scale factor, which is adaptively proportional to the difference of their gra...

Advanced imaging requires storage of large quantities of digitized data. Due to the constrained bandwidth and storage capacity, images must be compressed before transmission and storage. However the compression will reduce the image fidelity, especially when the images are compressed at lower bitrates. The reconstructed images suffer from blocking artifacts and the image quality will be severel...