The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Example-based super-resolution (SR) approaches mostly reconstruct and optimize the high-resolution (HR) image according to objective criteria such as imaging model. However, in consumer electronics applications the ultimate goal is better subjective visual effect rather than higher objective texture visibility. In this paper, we propose a SR method using perceptual visibility optimization (PVO). A...
Multi-view 3D surface reconstruction is typically formulated as minimizing an appropriate energy functional, which tends to find the empty set, i.e. an undesirable result, especially when cooperating only with a boundary term. So generally a regional term is employed, which indicates inside or outside of the surface. It is, however, the challenge because inherently there is no straightforward way...
Dense semantic segmentation of 3D point clouds is a challenging task. Many approaches deal with 2D semantic segmentation and can obtain impressive results. With the availability of cheap RGB-D sensors the field of indoor semantic segmentation has seen a lot of progress. Still it remains unclear how to deal with 3D semantic segmentation in the best way. We propose a novel 2D-3D label transfer based...
In this paper, an improved method of constructing FBP2D (3D) based variance map is introduced and implemented successfully. Accordingly, a quadratic version of distance driven back-projector (DD) compatible with variance reconstruction is developed to exploit fully the features of DD. As a result, the calculated variance is validated and shows an excellent match with ground truth.
Several methods have been developed for the sampling and reconstruction of specific classes of signals known as signals with finite rate of innovation (FRI). It is possible to recover the innovations of the signals from very low-rate samples by using adequate exponential reproduction sampling kernels. Recently, the FRI theory has been extended to arbitrary sampling kernels that reproduce approximate...
In this paper, we propose a simple and efficient motion deblurring method based on fast kernel retrieval method, which can quickly find the best kernel from a set of kernels. Owing to camera shake during exposure, it may generate a motion blurred image; this kind of blur is often nonlinear motion and caused the deterioration. For this reason, reconstructing a blurred image into a sharp image is the...
Alzheimer's disease (AD), also known as geriatric dementia, is the most serious dementia occurred among the elders whose age is over 65. Cognitive functions or memory will decay with age and are irreversible. The cause of dementia remains a mystery and the dementia population normally increases within aged societies. It is not only hard to diagnose whether an elderly will suffer from dementia but...
Single image super-resolution, namely increasing the resolution from only one coarse-resolution image, is a fundamental problem in computer vision. Although it has been extensively studied for decades, super-resolving a real-world image still remains challenging. In this paper, we propose a novel approach for image super-resolution by exploiting local self-similarity. First, we take advantage of this...
In this paper, we propose a kernel estimation algorithm using fast best kernel retrieval (FBKR) from spectral irregularities to achieve the deblurring. In daily life, when people take a photograph by any kinds of camera equipment, image motion blur caused by camera motion often happens. Camera motion during exposure will produce a blurred image, this kind of blur is often non-liner mode. Motion blur...
This paper aims to develop a novel framework of multi-cell tracking using intelligent ant system, in which a priori colony distribution block is first proposed to directly place birth ants on relevant pixels of current image through kernel density probability estimate of background; afterwards, a multi-colony reconstruction block is developed to further attract ants towards potential regions according...
The goal of the work was to understand the impact on clinical measures of timing resolution for time-of-flight (TOF) fully-3D iterative reconstruction. We compared TOF impact to that from use of a PET detector response model. Sixteen FDG-avid features in 13 whole-body FDG studies acquired on a TOF-capable PET/CT system were used. A NEMA image quality phantom was also studied for comparison and reconstruction...
This paper shows that the FBP algorithm is able to provide a solution to a weighted least-squares problem. Therefore, the projection noise model can be included in the FBP reconstruction. Bayesian information can also be incorporated in the FBP reconstruction.
Graphical processing units (GPUs) have become widely adopted in the medical imaging community. The parallel SIMD nature of GPUs maps perfectly to many reconstruction algorithms. Because of this, it is relatively straightforward to parallelize common reconstruction algorithms (e.g. FDK backprojection). This means that significant performance improvements must come from careful memory optimizations,...
Brain dedicated scanners such as the High Resolution Research Tomograph (HRRT) can achieve spatial resolutions of 2–3 mm FWHM due to their small scintillators crystal size and a double crystal layer phoswich detector which permits some level of depth of interaction (DOI) to minimise parallax errors. Resolution can further be improved by resolution models (RM) within image reconstruction which may...
There has been much work done in implementing various GPU-based Computed Tomography reconstruction algorithms for medical applications showing tremendous improvement in computational performance. While many of these reconstruction algorithms could also be applied to industrial-scale datasets, the performance gains may be modest to non-existent due to a combination of algorithmic, hardware, or scalability...
In the dual-head flat panel PET system (DHAPET), the unique detector arrangement leads to severe uncertainty of depth-of-interaction (DOI) and data truncation, which in turn result in poor image quality and data loss in the reconstructed images. To improve the distortions, we proposed a reconstruction strategy under the framework of the fast iterative shrinkage-thresholding algorithm (FISTA) for minimizing...
X-ray scatter signals acquired from a large flat panel detector in cone-beam computed tomography (CBCT) can degrade image quality of cross-section images. In this paper, we propose a new fast scatter correction method in CBCT using the statistical method in combination with the downsampling technique in projection images to reduce the computation time. The downsampled primary signal is estimated using...
This paper presents a new method for estimating a super-resolved version of an observed image by exploiting cross-scale self-similarity. We extend prior work on single-image super-resolution by introducing an adaptive selection of the best fitting upscaling and analysis filters for example learning. This selection is based on local error measurements obtained by using each filter with every image...
In this paper, we propose a novel image interpolation method using Gabor filter. It is significantly important to estimate edge direction accurately for image interpolation. For this, we adopt Gabor filter, which has been popularly used for texture-based feature extraction in object recognition. We exploit the superior point of Gabor filter, which is to detect small edges in texture region. By employing...
In this paper we present an effective method for super resolution (SR). The proposed method is inspired by the Non-Local Means (NLM) algorithm but shows a lot of improvements over it. Firstly, we show the sensitivity to the standard deviation parameter of the NLM algorithm in detail regions that has low contrast. This analysis leads to an improvement of the NLM algorithm by selecting the best neighbors...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.