515 research outputs found
Learning based automatic face annotation for arbitrary poses and expressions from frontal images only
Statistical approaches for building non-rigid deformable models, such as the active appearance model (AAM), have enjoyed great popularity in recent years, but typically require tedious manual annotation of training images. In this paper, a learning based approach for the automatic annotation of visually deformable objects from a single annotated frontal image is presented and demonstrated on the example of automatically annotating face images that can be used for building AAMs for fitting and tracking. This approach employs the idea of initially learning the correspondences between landmarks in a frontal image and a set of training images with a face in arbitrary poses. Using this learner, virtual images of unseen faces at any arbitrary pose for which the learner was trained can be reconstructed by predicting the new landmark locations and warping the texture from the frontal image. View-based AAMs are then built from the virtual images and used for automatically annotating unseen images, including images of different facial expressions, at any random pose within the maximum range spanned by the virtually reconstructed images. The approach is experimentally validated by automatically annotating face images from three different databases
Imaging Cultural Heritage at Different Scales: Part I, the Micro-Scale (Manufacts)
Applications of non-invasive sensing techniques to investigate the internal structure and
surface of precious and delicate objects represent a very important and consolidated research field in
the scientific domain of cultural heritage knowledge and conservation. The present article is the first of three reviews focused on contact and non-contact imaging techniques applied to surveying cultural heritage at micro- (i.e., manufacts), meso- (sites) and macro-scales (landscapes). The capability to
infer variations in geometrical and physical properties across the inspected surfaces or volumes is the unifying factor of these techniques, allowing scientists to discover new historical sites or to image their spatial extent and material features at different scales, from landscape to artifact. This first part concentrates on the micro-scale, i.e., inspection, study and characterization of small objects (ancient papers, paintings, statues, archaeological findings, architectural elements, etc.) from surface
to internal properties
A framework of face recognition with set of testing images
We propose a novel framework to solve the face recognition problem base on set of testing images. Our framework can handle the case that no pose overlap between training set and query set. The main techniques used in this framework are manifold alignment, face normalization and discriminant learning. Experiments on different databases show our system outperforms some state of the art methods
Application of probabilistic modeling and automated machine learning framework for high-dimensional stress field
Modern computational methods, involving highly sophisticated mathematical
formulations, enable several tasks like modeling complex physical phenomenon,
predicting key properties and design optimization. The higher fidelity in these
computer models makes it computationally intensive to query them hundreds of
times for optimization and one usually relies on a simplified model albeit at
the cost of losing predictive accuracy and precision. Towards this, data-driven
surrogate modeling methods have shown a lot of promise in emulating the
behavior of the expensive computer models. However, a major bottleneck in such
methods is the inability to deal with high input dimensionality and the need
for relatively large datasets. With such problems, the input and output
quantity of interest are tensors of high dimensionality. Commonly used
surrogate modeling methods for such problems, suffer from requirements like
high number of computational evaluations that precludes one from performing
other numerical tasks like uncertainty quantification and statistical analysis.
In this work, we propose an end-to-end approach that maps a high-dimensional
image like input to an output of high dimensionality or its key statistics. Our
approach uses two main framework that perform three steps: a) reduce the input
and output from a high-dimensional space to a reduced or low-dimensional space,
b) model the input-output relationship in the low-dimensional space, and c)
enable the incorporation of domain-specific physical constraints as masks. In
order to accomplish the task of reducing input dimensionality we leverage
principal component analysis, that is coupled with two surrogate modeling
methods namely: a) Bayesian hybrid modeling, and b) DeepHyper's deep neural
networks. We demonstrate the applicability of the approach on a problem of a
linear elastic stress field data.Comment: 17 pages, 16 figures, IDETC Conference Submissio
Imaging cultural heritage at different scales : part I, the micro-scale (manufacts)
Applications of non-invasive sensing techniques to investigate the internal structure and
surface of precious and delicate objects represent a very important and consolidated research field in
the scientific domain of cultural heritage knowledge and conservation. The present article is the first
of three reviews focused on contact and non-contact imaging techniques applied to surveying cultural
heritage at micro- (i.e., manufacts), meso- (sites) and macro-scales (landscapes). The capability to
infer variations in geometrical and physical properties across the inspected surfaces or volumes
is the unifying factor of these techniques, allowing scientists to discover new historical sites or to
image their spatial extent and material features at different scales, from landscape to artifact. This
first part concentrates on the micro-scale, i.e., inspection, study and characterization of small objects
(ancient papers, paintings, statues, archaeological findings, architectural elements, etc.) from surface
to internal properties.peer-reviewe
Recommended from our members
3D multiresolution statistical approaches for accelerated medical image and volume segmentation
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Medical volume segmentation got the attraction of many researchers; therefore, many techniques have been implemented in terms of medical imaging including segmentations and other imaging processes. This research focuses on an implementation of segmentation system which uses several techniques together or on their own to segment medical volumes, the system takes a stack of 2D slices or a full 3D volumes acquired from medical scanners as a data input.
Two main approaches have been implemented in this research for segmenting medical volume which are multi-resolution analysis and statistical modeling. Multi-resolution analysis has been mainly employed in this research for extracting the features. Higher dimensions of discontinuity (line or curve singularity) have been extracted in medical images using a modified multi-resolution analysis transforms such as ridgelet and curvelet transforms.
The second implemented approach in this thesis is the use of statistical modeling in medical image segmentation; Hidden Markov models have been enhanced here to segment medical slices automatically, accurately, reliably and with lossless results. But the problem with using Markov models here is the computational time which is too long. This has been addressed by using feature reduction techniques which has also been implemented in this thesis. Some feature reduction and dimensionality reduction techniques have been used to accelerate the slowest block in the proposed system. This includes Principle Components Analysis, Gaussian Pyramids and other methods. The feature reduction techniques have been employed efficiently with the 3D volume segmentation techniques such as 3D wavelet and 3D Hidden Markov models.
The system has been tested and validated using several procedures starting at a comparison with the predefined results, crossing the specialists’ validations, and ending by validating the system using a survey filled by the end users explaining the techniques and the results. This concludes that Markovian models segmentation results has overcome all other techniques in most patients’ cases. Curvelet transform has been also proved promising segmentation results; the end users rate it better than Markovian models due to the long time required with Hidden Markov models
- …