Search results for "image processing"
showing 10 items of 3285 documents
Multi-label Classification Using Stacked Hierarchical Dirichlet Processes with Reduced Sampling Complexity
2018
Nonparametric topic models based on hierarchical Dirichlet processes (HDPs) allow for the number of topics to be automatically discovered from the data. The computational complexity of standard Gibbs sampling techniques for model training is linear in the number of topics. Recently, it was reduced to be linear in the number of topics per word using a technique called alias sampling combined with Metropolis Hastings (MH) sampling. We propose a different proposal distribution for the MH step based on the observation that distributions on the upper hierarchy level change slower than the document-specific distributions at the lower level. This reduces the sampling complexity, making it linear i…
A Survey of Multi-Label Topic Models
2019
Every day, an enormous amount of text data is produced. Sources of text data include news, social media, emails, text messages, medical reports, scientific publications and fiction. To keep track of this data, there are categories, key words, tags or labels that are assigned to each text. Automatically predicting such labels is the task of multi-label text classification. Often however, we are interested in more than just the pure classification: rather, we would like to understand which parts of a text belong to the label, which words are important for the label or which labels occur together. Because of this, topic models may be used for multi-label classification as an interpretable mode…
Open-source software tools for measuring resources consumption and DASH metrics
2020
When designing and deploying multimedia systems, it is essential to accurately know about the necessary requirements and the Quality of Service (QoS) offered to the customers. This paper presents two open-source software tools that contribute to these key needs. The first tool is able to measure and register resources consumption metrics for any Windows program (i.e. process id), like the CPU, GPU and RAM usage. Unlike the Task Manager, which requires manual visual inspection for just a subset of these metrics, the developed tool runs on top of the Powershell to periodically measure these metrics, calculate statistics, and register them in log files. The second tool is able to measure QoS m…
Capacity-based calculation of passenger car equivalents using traffic simulation at double-lane roundabouts
2018
Abstract Calculation of passenger car equivalents for heavy vehicles represents the starting point for the operational analysis of road facilities and other traffic management applications. This paper introduces a criterion to find the passenger car equivalents that reflect traffic conditions at double-lane roundabouts, where the capacity is typically estimated for each entry lane. Based on the equivalence defined by the proportion of capacity used by vehicles of different classes, the criterion implies a comparison between the capacity that would occur with a traffic demand of passenger cars only and the capacity reached beginning from a demand with a certain percentage of heavy vehicles. …
Learning Similarity Scores by Using a Family of Distance Functions in Multiple Feature Spaces
2017
There exist a large number of distance functions that allow one to measure similarity between feature vectors and thus can be used for ranking purposes. When multiple representations of the same object are available, distances in each representation space may be combined to produce a single similarity score. In this paper, we present a method to build such a similarity ranking out of a family of distance functions. Unlike other approaches that aim to select the best distance function for a particular context, we use several distances and combine them in a convenient way. To this end, we adopt a classical similarity learning approach and face the problem as a standard supervised machine lea…
Tomographic image processing for the morphological and metrological study of Valsalva sinuses
2012
This Phd thesis deals with the design and the use of image processing tools in order to allow a reliable and objective study of the sinuses of Valsalva which are important cavities of the aortic root. The proposed methods can be applied on cine-MR sequences and CT examinations without any change in the settings between two examinations.Firstly, we studied the morphology of this anatomical area and its constant properties in all images of the dataset. Sinuses are one of the main bright organs with limited movements. Hence a new algorithm has been designed. It detects and characterizes each bright organ by a single trajectory. Various tools of mathematical morphology are used for this step, a…
Texture analysis with statistical methods for wheat ear extraction
2007
In agronomic domain, the simplification of crop counting, necessary for yield prediction and agronomic studies, is an important project for technical institutes such as Arvalis. Although the main objective of our global project is to conceive a mobile robot for natural image acquisition directly in a field, Arvalis has proposed us first to detect by image processing the number of wheat ears in images before to count them, which will allow to obtain the first component of the yield. In this paper we compare different texture image segmentation techniques based on feature extraction by first and higher order statistical methods which have been applied on our images. The extracted features are…
Projective unification in transitive modal logics
2018
We show that a transitive normal modal logic L enjoys projective unification (i.e. each unifiable formula is projective) if and only if L contains K4D1 ( D1 : ( x → y ) ∨ ( y → x ) ). It means, in particular, that K4D1 (and any of its extensions) is almost structurally complete, i.e. the logic is complete with respect to all non-passive admissible rules. We also characterize non-unifiable formulas and provide an explicit form of the basis for all passive rules over K4G + ( x → x )
Probabilistic semantics for categorical syllogisms of Figure II
2018
A coherence-based probability semantics for categorical syllogisms of Figure I, which have transitive structures, has been proposed recently (Gilio, Pfeifer, & Sanfilippo [15]). We extend this work by studying Figure II under coherence. Camestres is an example of a Figure II syllogism: from Every P is M and No S is M infer No S is P. We interpret these sentences by suitable conditional probability assessments. Since the probabilistic inference of \(\bar{P}|S\) from the premise set \(\{M|P,\bar{M}|S\}\) is not informative, we add \(p(S|(S \vee P))>0\) as a probabilistic constraint (i.e., an “existential import assumption”) to obtain probabilistic informativeness. We show how to propagate the…
Augmented reality based middle and inner ear surgical procedures
2020
Otologic procedures involve manipulation of small, delicate and complex structures in the temporal bone anatomy which are in close proxmity of critical nerves and blood vessels. Augmented reality (AR) can highly benefit the otological domain by providing supplementary anatomical and navigational information unified on a single display. However, despite being composed of mainly rigid bony structures, the awareness and acceptance of possibilities of AR systems in otology is fairly low. This project aims at developing video-based AR solutions for middle and inner ear surgical procedures.We propose two applications of AR in this regard. In the first application, information about middle ear cle…