Now showing items 1-20 of 61

    • A block adaptive pyramid coding system 

      Sallent Ribes, Sebastián; Torres Urgell, Lluís; Triola Espigulé, Albert (1988)
      Conference report
      Open Access
      In this paper we present a new block adaptive coding scheme which uses non-rectangular Laplacian Pyramid Algorithms. The proposed method JB adapted to the local image contents. The original image is broken into subimages ...
    • A contribution to video coding using layers 

      Torres Urgell, Lluís; Lecha, M (1998)
      Conference report
      Open Access
      Layered representations of video sequences, originally introduced in [1], are important in several applications. Specifically, they are very appropriate for object tracking, object manipulation, content-based scalability ...
    • A feature-based subband coding scheme 

      Casas Pla, Josep Ramon; Torres Urgell, Lluís (Institute of Electrical and Electronics Engineers (IEEE), 1996)
      Conference report
      Restricted access - publisher's policy
      A feature-based subband coding scheme is presented. It is intended for the coding of the texture component of a two-component image model. The primary component contains the strong edges, individually described by their ...
    • A new adaptive method for image compression using Karhunen-Loeve transform 

      Torres Urgell, Lluís (Institute of Electrical and Electronics Engineers (IEEE), 1987)
      Conference report
      Open Access
      The Karhunen-Loeve transformation (KLT) is an optimal method for encoding images in the MSE sense. Only one spatially adaptive method is known to be reported in the literature. Many other suboptimal encoding methods have ...
    • A new approach to texture coding using stochastic vector quantization 

      Gimeno, D; Torres Urgell, Lluís; Casas Pla, Josep Ramon (IEEE Computer Society, 1994)
      Conference report
      Open Access
      A new method for texture coding which combines 2-D linear prediction and stochastic vector quantization is presented in this paper. To encode a texture, a linear predictor is computed first. Next, a codebook following the ...
    • A non-rectangular pyramid coding system 

      Sallent Ribes, Sebastián; Torres Urgell, Lluís (1988)
      Conference report
      Open Access
      Rectangular sampling lattices bave been extensively applied to image coding. Sampling is a fundamental orera.tion m image coding systems as a proper selection of the sampling lattice minimizes the physica support of the ...
    • A region-based subband coding scheme 

      Casas Pla, Josep Ramon; Torres Urgell, Lluís (1997-07)
      Article
      Restricted access - publisher's policy
      This paper describes a region-based subband coding scheme intended for efficient representation of the visual information contained in image regions of arbitrary shape. QMF filters are separately applied inside each region ...
    • A robust motion estimation and segmentation approach to represent moving images with layers 

      Torres Urgell, Lluís; García Luque, David; MATES, A (IEEE COMPUTER SOCIETY, 1997)
      Conference report
      Open Access
      The paper provides a robust representation of moving images based on layers. To that goal, we have designed efficient motion estimation and segmentation techniques by affine model fitting suitable for the construction of ...
    • A simple and efficient face detection algorithm for video database applications 

      Albiol, A; Torres Urgell, Lluís; Delp, E; Bouman, C (Institute of Electrical and Electronics Engineers (IEEE), 2000)
      Conference report
      Open Access
      The objective of this work is to provide a simple and yet efficient tool to detect human faces in video sequences. This information can be very useful for many applications such as video indexing and video browsing. In ...
    • Actividades en procesado de la imagen del Grupo de Procesado de Señal 

      Marqués Acosta, Fernando; Gasull Llampallas, Antoni; Torres Urgell, Lluís (Escola Tècnica Superior d'Enginyers de Telecomunicació de Barcelona, 1993)
      Article
      Open Access
    • Algoritmos de clasificacion de contenido visual 

      Raventós, Arnau; Mur, Olga; Martin Cirera, Albert; Quijada Ferrero, Raúl; Tarrés Ruiz, Francisco; Torres Urgell, Lluís (2012-06-26)
      External research report
      Restricted access - confidentiality agreement
      Entregable E.3.2.1.
    • Algoritmos de clasificación de eventos simples a partir de descriptores multimodales 

      Quijada Ferrero, Raúl; Raventós, Arnau; Martin Cirera, Albert; Torres Urgell, Lluís; Tarrés Ruiz, Francisco (2012-02-15)
      External research report
      Restricted access - confidentiality agreement
      Deriberable 4.1.1
    • An adaptive pyramid image coding system 

      Torres Urgell, Lluís; Sallent Ribes, Sebastián (Institute of Electrical and Electronics Engineers (IEEE), 1988)
      Conference report
      Open Access
      The Laplacian Pyramid is a new and efficient method for image encoding. The method is of increasing interest as band-pass pyramids and multiresolution images are being used in other image processing applications. The Pyramid ...
    • An efficient technique of texture representation in segmentation-based image coding schemes 

      Torres Urgell, Lluís; Casas Pla, Josep Ramon; Campins, J (IEEE IEEE, 1995)
      Conference report
      Open Access
      In segmentation-based image coding techniques the image to be compressed is first segmented. Then, the information is coded describing the shape and the interior of the regions. A new method to encode the texture obtained ...
    • An improvement on codebook search for vector quantization 

      Torres Urgell, Lluís; Huguet, J (1994-02)
      Article
      Open Access
      Presents a simple but effective algorithm to speed up the codebook search in a vector quantization scheme when a MSE criterion is used. A considerable reduction in the number of operations is achieved. This algorithm was ...
    • Analysis and synthesis of textures through the inference of Boolean functions 

      Domínguez Pumar, Manuel; Torres Urgell, Lluís (1997-05)
      Article
      Restricted access - publisher's policy
      This work deals with Boolean functions of non-linear and linear basis. The Boolean random functions of non-linear basis were proposed by Serra (1988,1989). These functions are generated through a Poisson point process upon ...
    • Análisis de no estacionariedades en la interpolación de imágenes. Aplicación a codificación piramidal y zoom 

      Gasull Llampallas, Antoni; Marqués Acosta, Fernando; Torres Urgell, Lluís (1991)
      Conference report
      Open Access
      In some applications of digital image processing the fact that an image is a non estacionary signal can cause some undesirable effects. That is the case of block effect in transform coding, or destructive effects on contours ...
    • Anotaciones de las bases de datos 

      Mindan, Pere J.; Raventós, Arnau; Mur, Olga; Tarrés Ruiz, Francisco; Torres Urgell, Lluís (2011-11-30)
      External research report
      Restricted access - confidentiality agreement
      Entregable 1.2.2
    • Automatic face recognition of video sequences using self-eigenfaces 

      Torres Urgell, Lluís; Lorente, Luis; Vilà Guerau de Arellano, Jordi (-, 2000)
      Conference report
      Open Access
      The objective of this work is to provide an efficient face recognition scheme useful for video indexing applications. In particular we are addressing the following problem: given a set of known images and given a video ...
    • Automatic left ventricular contour extraction for volume calculation from echocardiographic images 

      Gasull Llampallas, Antoni; Torres Urgell, Lluís; Marqués Acosta, Fernando; Vázquez Grau, Gregorio (1989)
      Conference report
      Open Access
      This paper presents a new fully automated algorithm that extracts LV epicardial and endocardial borders from 2-D echocardiograms. The method is based on a radial search approach, which is the best way to use some a priori ...