A 2D Shape Structure for Decomposition and Part Similarity

International audienceThis paper presents a multilevel analysis of 2D shapes and uses it to find similarities between the different parts of a shape. Such an analysis is important for many applications such as shape comparison, editing, and compression. Our robust and stable method decomposes a shape into parts, determines a parts hierarchy, and measures similarity between parts based on a salience measure on the medial axis, the Weighted Extended Distance Function, providing a multi-resolution partition of the shape that is stable across scale and articulation. Comparison with an extensive user study on the MPEG-7 database demonstrates that our geometric results are consistent with user perception

How do women prepare for pregnancy? Preconception experiences of women attending antenatal services and views of health professionals

Copyright: © 2014 Stephenson et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Main objective - To determine the extent to which women plan and prepare for pregnancy. Methods - Cross-sectional questionnaire survey of pregnant women attending three maternity services in London about knowledge and uptake of preconception care; including a robust measure of pregnancy planning, and phone interviews with a range of health care professionals. Main results - We recruited 1173/1288 (90%) women, median age of 32 years. 73% had clearly planned their pregnancy, 24% were ambivalent and only 3% of pregnancies were unplanned. 51% of all women and 63% of those with a planned pregnancy took folic acid before pregnancy. 21% of all women reported smoking and 61% reported drinking alcohol in the 3 months before pregnancy; 48% of smokers and 41% of drinkers reduced or stopped before pregnancy. The 51% of all women who reported advice from a health professional before becoming pregnant were more likely to adopt healthier behaviours before pregnancy [adjusted odds ratios for greatest health professional input compared with none were 2.34 (95% confidence interval 1.54–3.54) for taking folic acid and 2.18 (95% CI 1.42–3.36) for adopting a healthier diet before pregnancy]. Interviews with 20 health professionals indicated low awareness of preconception health issues, missed opportunities and confusion about responsibility for delivery of preconception care. Significance of the findings - Despite a high level of pregnancy planning, awareness of preconception health among women and health professionals is low, and responsibility for providing preconception care is unclear. However, many women are motivated to adopt healthier behaviours in the preconception period, as indicated by halving of reported smoking rates in this study. The link between health professional input and healthy behaviour change before pregnancy is a new finding that should invigorate strategies to improve awareness and uptake of pre-pregnancy health care, and bring wider benefits for public health.Department of Healt

The 2D shape structure dataset: A user annotated open access database

International audienceIn this paper we present the 2D Shape Structure database, a public, user-generated dataset of 2D shape decompositions into a hierarchy of shape parts with geometric relationships retained. It is the outcome of a large-scale user study obtained by crowdsourcing, involving over 1200 shapes in 70 shape classes, and 2861 participants. A total of 41953 annotations has been collected with at least 24 annotations per shape. For each shape, user decompositions into main shape, one or more levels of parts, and a level of details are available. This database reinforces a philosophy that understanding shape structure as a whole, rather than in the separated categories of parts decomposition, parts hierarchy, and analysis of relationships between parts, is crucial for full shape understanding. We provide initial statistical explorations of the data to determine representative (" mean ") shape annotations and to determine the number of modes in the annotations. The primary goal of the paper is to make this rich and complex database openly available (through the website http://2dshapesstructure.github.io/index.html), providing the shape community with a ground truth of human perception of holistic shape structure

Evaluation of the psychometric properties of the London Measure of Unplanned Pregnancy in Brazilian Portuguese

Background: Estimates of unplanned pregnancy worldwide are of concern, especially in low and middle-income countries, including Brazil. Although the contraceptive prevalence rate is high in Brazil, almost half of all pregnancies are reported as unintended. The only source of nationally representative data about pregnancy intention is the Demographic and Health Survey, as with many other countries. In more recent years, however, it has been realized that concept of unintended pregnancy is potentially more complex and requires more sophisticated measurement strategies, such as the London Measure of Unplanned Pregnancy (LMUP). The LMUP has been translated and validated in other languages, but not Portuguese yet. In this study, we evaluate the psychometric properties of the LMUP in the Portuguese language, Brazilian version. Methods: A Brazilian Portuguese version of the LMUP was produced via translation and back-translation. After piloting, the mode of administration was changed from self-completion to interviewer-administration. The measure was field tested with pregnant, postpartum, and postabortion women recruited at maternity and primary health care services in Sao Paulo city. Reliability (internal consistency) was assessed using Cronbach’s alpha and item-total correlations. Construct validity was assessed using principal components analysis and hypothesis testing. Scaling was assessed with Mokken analysis. Results: 759 women aged 15–44 completed the Brazilian Portuguese LMUP. There were no missing data. The measure was acceptable and well targeted. Reliability testing demonstrated good internal consistency (alpha = 0.81, all item-rest correlations >0.2). Validity testing confirmed that the measure was unidimensional and that all hypotheses were met: there were lower LMUP median scores among women in the extreme age groups (p<0.001), among non-married women (p<0.001) and those with lower educational attainment (p<0.001). The Loevinger H coefficient was 0.60, indicating a strong scale. Conclusion: The Brazilian Portuguese LMUP is a valid and reliable measure of pregnancy planning/intention that is now available for use in Brazil. It represents a useful addition to the public health research and surveillance toolkit in Brazil

Analytic functions in computer-aided geometric design

This thesis presents a new paradigm for geometric modeling based on analytic functions. This model includes not only a representation of analytic curves and surfaces, but also tools and algorithms to manipulate this representation. Analytic functions on a given domain represent a very large class of infinitely smooth functions, including trigonometric functions and functions with poles outside the domain. Thus, the model is very rich; in particular the model is able to represent an object of optimal smoothness as well as functions as close as desired to singularities. The Bezier representation for polynomials generalizes to the Poisson representation for analytic curves and surfaces. The coefficients in the Poisson basis not only characterize an analytic function, but also are geometrically meaningful and intuitive control parameters for the curve or surface the function defines---as the Bezier control points are for polynomial shapes. Based on this Poisson representation, we derive standard geometric modeling algorithms for analytic curves and surfaces, including subdivision, trimming, evaluation and change of basis procedures. We also develop a notion of blossoming, as well as a de Boor-Fix formula and a Marsden identity, for analytic curves. These algorithms and tools provide an efficient and complete framework for using analytic functions in geometric modeling

Texturing and inpainting a complete tubular 3D object reconstructed from partial views

International audienceWe present a novel approach to texture 3D tubular objects reconstructed from partial views. Starting from few images of the object, we rely on a 3D reconstruction approach that provides a representation of the object based on a composition of several parametric surfaces, more specifically canal surfaces. Such representation enables a complete reconstruction of the object even for the parts that are hidden or not visible by the input images. The proposed texturing method maps the input images on the parametric surface of the object and complete parts of the surface not visible in any image through an inpainting process. In particular, we first propose a method to select, for each 3D canal surface, the most suitable images and fuse them together for texturing the surface. This process is regulated by a confidence criterion that selects images based on their position and orientation w.r.t. the surface. We also introduce a global method to fuse the images taking into account their exposure difference. Finally, we propose two methods to complete or inpaint the texture in the hidden parts of the surface according to the type of the texture

Blind Quality of a 3D Reconstructed Mesh

International audienceThis paper proposes blind mesh quality measures for a reconstructed 3D model. The assessment of 3D model quality is a fundamental step in the process of 3D reconstruction, to efficiently and iteratively improve the model quality. We first prove that metrics based on a reference model (extrinsic metrics) that have been shown to be correlated to subjective interpretation, are able to capture flaws that may occur while reconstructing. However, no reference is available during an iterative reconstruction process, so we study intrinsic measures on a 3D model to evaluate the quality of the 3D model being reconstructed. As expected, our results show that these intrinsic metrics give high responses in regions locally corrupted by noises

Radiometric confidence criterion for patch-based inpainting

International audienceDiminished Reality (DR) consists in virtually removing objects from a captured scene, thus requiring a coherent filling of the areas originally hidden behind these objects. Indoor DR applications often exploit the planar geometry of the scene to apply an inpainting process on a perspectively undistorted view of the plane. In this paper we propose to integrate a novel, physic-based criterion into classical state-of-the-art inpainting algorithms in order to take into account the variations in image resolution of the undistorted view. The proposed inpainting process selects the patches and avoids the propagation of low-resolution data, i.e. patches corresponding to parts of the plane that are far from the camera or seen under an very skew angle. We illustrate the improvements of DR results on synthetic and real images