|   | 
Details
   web
Records
Author Ole Larsen; Petia Radeva; Enric Marti
Title Bounds on the optimal elasticity parameters for a snake Type Journal Article
Year 1995 Publication Image Analysis and Processing Abbreviated Journal
Volume Issue Pages 37-42
Keywords
Abstract This paper develops a formalism by which an estimate for the upper and lower bounds for the elasticity parameters for a snake can be obtained. Objects different in size and shape give rise to different bounds. The bounds can be obtained based on an analysis of the shape of the object of interest. Experiments on synthetic images show a good correlation between the estimated behaviour of the snake and the one actually observed. Experiments on real X-ray images show that the parameters for optimal segmentation lie within the estimated bounds.
Address
Corporate Author Thesis
Publisher Place of Publication Editor (up)
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes MILAB;IAM Approved no
Call Number IAM @ iam @ LRM1995a Serial 1559
Permanent link to this record
 

 
Author Josep Llados; Enric Marti
Title Interpretacio de dibuixos lineals mitjançant tècniques d isomorfisme entre grafs Type Conference Article
Year 1995 Publication Trobada de Joves Investigadors Abbreviated Journal
Volume Issue Pages
Keywords
Abstract L’anàlisi de documents té com a objectiu la interpretació automàtica de documents impresos sobre paper, amb la finalitat d’obtenir una descripció simbòlica d’aquests, que permeti el seu emmagatzemament i posterior tractament computacional. Les tècniques basades en grafs relacionals d’atributs permeten representar de manera compacta la informació continguda en dibuixos lineals i mitjançant mecanismes d’isomorfisme entre grafs, reconèixer-hi certes estructures i d’aquesta manera, interpretar el document. En aquest treball es dóna una visió general de les tènciques de grafs aplicades al reconeixement visual d’objectes en problemes d’anàlisi de documents. Aquestes tècniques s’il·lustren amb un exemple de reconeixement de plànols dibuixats a mà alçada. Finalment es proposa la utilització de tècniques de Hough com a mecanisme per accelerar el procés de reconeixement aplicant un cert coneixement sobre el domini en el que es treballa
Address
Corporate Author Thesis
Publisher Place of Publication Editor (up)
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes DAG;IAM Approved no
Call Number IAM @ iam @ LlM1995 Serial 1578
Permanent link to this record
 

 
Author Petia Radeva; Enric Marti
Title An improved model of snakes for model-based segmentation Type Conference Article
Year 1995 Publication Proceedings of Computer Analysis of Images and Patterns Abbreviated Journal
Volume Issue Pages 515-520
Keywords
Abstract The main advantage of segmentation by snakes consists in its ability to incorporate smoothness constraints on the detected shapes that can occur. Likewise, we propose to model snakes with other properties that reflect the information provided about the object of interest in a different extent. We consider different kinds of snakes, those searching for contours with a certain direction, those preserving an object’s model, those seeking for symmetry, those expanding open, etc. The availability of such a collection of snakes allows not only the more complete use of the knowledge about the segmented object, but also to solve some problems of the existing snakes. Our experiments on segmentation of facial features justify the usefulness of snakes with different properties.
Address
Corporate Author Thesis
Publisher Place of Publication Editor (up)
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference CAIP
Notes MILAB;IAM Approved no
Call Number IAM @ iam @ RaM1995b Serial 1632
Permanent link to this record
 

 
Author Petia Radeva; Enric Marti
Title Facial Features Segmentation by Model-Based Snakes Type Conference Article
Year 1995 Publication International Conference on Computing Analysis and Image Processing Abbreviated Journal
Volume Issue Pages
Keywords
Abstract Deformable models have recently been accepted as a standard technique to segment different features in facial images. Despite they give a good approximation of the salient features in a facial image, the resulting shapes of the segmentation process seem somewhat artificial with respect to the natural feature shapes. In this paper we show that active contour models (in particular, rubber snakes) give more close and natural representation of the detected feature shape. Besides, using snakes for facial segmentation frees us from the problem of determination of the numerous weigths of deformable models. Another advantage of rubber snakes is their reduced computational cost. Our experiments using rubber snakes for segmentation of facial snapshots have shown a significant improvement compared to deformable models.
Address
Corporate Author Thesis
Publisher Place of Publication Bellaterra (Barcelona), Spain Editor (up)
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes MILAB;IAM Approved no
Call Number IAM @ iam @ RAM1995a Serial 1633
Permanent link to this record
 

 
Author Petia Radeva; Joan Serrat; Enric Marti
Title A snake for model-based segmentation Type Conference Article
Year 1995 Publication Proc. Conf. Fifth Int Computer Vision Abbreviated Journal
Volume Issue Pages 816-821
Keywords snakes; elastic matching; model-based segmenta tion
Abstract Despite the promising results of numerous applications, the hitherto proposed snake techniques share some common problems: snake attraction by spurious edge points, snake degeneration (shrinking and attening), convergence and stability of the deformation process, snake initialization and local determination of the parameters of elasticity. We argue here that these problems can be solved only when all the snake aspects are considered. The snakes proposed here implement a new potential eld and external force in order to provide a deformation convergence, attraction by both near and far edges as well as snake behaviour selective according to the edge orientation. Furthermore, we conclude that in the case of model-based seg mentation, the internal force should include structural information about the expected snake shape. Experiments using this kind of snakes for segmenting bones in complex hand radiographs show a signi cant improvement.
Address
Corporate Author Thesis
Publisher Place of Publication Editor (up)
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes MILAB;ADAS;IAM Approved no
Call Number IAM @ iam @ RSM1995 Serial 1634
Permanent link to this record