149 research outputs found
3D functional models of monkey brain through elastic registration of histological sections
In this paper we describe a method for the reconstruction and visualization of functional models of monkey brains. Models are built through the registration of high resolution images obtained from the scanning of histological sections with reference photos taken during the brain slicing. From the histological sections it is also possible to acquire specifically activated neuron coordinates introducing functional information in the model. Due to the specific nature of the images (texture information is useless and the sections could be deformed when they were cut and placed on glass) we solved the registration problem by extracting corresponding cerebral cortex borders (extracted with a snake algorithm), and computing from their deformation an image transform modeled as an affine deformation plus a non-linear field evaluated as an elastically constrained deformation minimizing contour distances. Registered images and contours are used then to build 3D models of specific brains by a software tool allowing the interactive visualization of cortical volumes together with the spatially referenced neurons classified and differently colored according to their functionalities
Fast Mesh-Based Medical Image Registration
In this paper a fast triangular mesh based registration method is proposed.
Having Template and Reference images as inputs, the template image is
triangulated using a content adaptive mesh generation algorithm. Considering
the pixel values at mesh nodes, interpolated using spline interpolation method
for both of the images, the energy functional needed for image registration is
minimized. The minimization process was achieved using a mesh based
discretization of the distance measure and regularization term which resulted
in a sparse system of linear equations, which due to the smaller size in
comparison to the pixel-wise registration method, can be solved directly. Mean
Squared Difference (MSD) is used as a metric for evaluating the results. Using
the mesh based technique, higher speed was achieved compared to pixel-based
curvature registration technique with fast DCT solver. The implementation was
done in MATLAB without any specific optimization. Higher speeds can be achieved
using C/C++ implementations.Comment: Accepted manuscript for ISVC'201
Visible and Infrared Image Registration Employing Line-Based Geometric Analysis
Abstract. We present a new method to register a pair of visible (ViS) and infrared (IR) images. Unlike most of existing systems that align interest points of two images, we align lines derived from edge pixels, because the interest points extracted from both images are not always identical, but most major edges detected from one image do appear in another image. To solve feature matching problem, we emphasize the geometric structure alignment of features (lines), instead of descriptor-based individual feature matching. This is due to the fact that image properties and patch statistics of corresponding features might be quite different, especially when one compares ViS image with long wave IR images (thermal information). However, the spatial layout of features for both images always preserves consistency. The last step of our algorithm is to compute the image transform matrix, given minimum 4 pairs of line correspondence. The comparative evaluation for algorithms demon-strates higher accuracy attained by our method when compared to the state-of-the-art approaches.
The application of big data and AI in the upstream supply chain
The use of Big Data has grown in popularity in organisations to exploit the purpose of their primary data to enhance their competitiveness. In conjunction with the increased use of Big Data, there has also been a growth in the use of Artificial Intelligence (AI) to analyse the vast amounts of data generated and provide a mechanism for locating and constructing useable patterns that organisations can incorporate in their supply chain strategy programme. As these organisations embrace the use of technology and embed this in their supply chain strategy, there are questions as to how this may affect their upstream supply chains especially with regards to how SME’s may be able to cope with the potential changes. There exists the opportunity to conduct further research into this area, mainly focusing on three key industry sectors of aerospace, rail and automotive supply chains.N/
Color image registration under illumination changes
The estimation of parametric global motion has had a significant attention
during the last two decades, but despite the great efforts invested, there
are still open issues. One of the most important ones is related to the ability to recover
large deformation between images in the presence of illumination changes
while kipping accurate estimates. Illumination changes in color images are another
important open issue. In this paper, a Generalized least squared-based motion
estimator is used in combination with color image model to allow accurate
estimates of global motion between two color images under the presence of large
geometric transformation and illumination changes. Experiments using challenging
images have been performed showing that the presented technique is feasible
and provides accurate estimates of the motion and illumination parameter
Automatic Optimization of Alignment Parameters for Tomography Datasets
As tomographic imaging is being performed at increasingly smaller scales, the stability of the scanning hardware
is of great importance to the quality of the reconstructed image. Instabilities lead to perturbations in the
geometrical parameters used in the acquisition of the projections. In particular for electron tomography
and high-resolution X-ray tomography, small instabilities in the imaging setup can lead to severe artifacts.
We present a novel alignment algorithm for recovering the true geometrical parameters \emph{after} the object
has been scanned, based on measured data.
Our algorithm employs an optimization algorithm that combines alignment with reconstruction.
We demonstrate that problem-specific design choices made in the implementation are vital to the success of the method. The algorithm
is tested in a set of simulation experiments. Our experimental results indicate that the method is capable of
aligning tomography datasets with considerably higher accuracy compared to standard cross-correlation methods
Selection of massive bone allografts using shape-matching 3-dimensional registration
Background and purpose Massive bone allografts are used when surgery causes large segmental defects. Shape-matching is the primary criterion for selection of an allograft. The current selection method, based on 2-dimensional template comparison, is inefficient for 3-dimensional complex bones. We have analyzed a 3-dimensional (3-D) registration method to match the anatomy of the allograft with that of the recipient
Advances in multispectral and hyperspectral imaging for archaeology and art conservation
Multispectral imaging has been applied to the field of art conservation and art history since the early 1990s. It is attractive as a noninvasive imaging technique because it is fast and hence capable of imaging large areas of an object giving both spatial and spectral information. This paper gives an overview of the different instrumental designs, image processing techniques and various applications of multispectral and hyperspectral imaging to art conservation, art history and archaeology. Recent advances in the development of remote and versatile multispectral and hyperspectral imaging as well as techniques in pigment identification will be presented. Future prospects including combination of spectral imaging with other noninvasive imaging and analytical techniques will be discussed
Articulated Whole-Body Atlases for Small Animal Image Analysis: Construction and Applications
Bone and mineral researc
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