We propose an improved search procedure for Active Shape Model (ASM) based delineation of anatomi... more We propose an improved search procedure for Active Shape Model (ASM) based delineation of anatomical structures in digital X-ray images. Whereas the original ASM search method [1] iteratively improves the current estimate of the location of boundary points by a limited least squares adjustment of the pose and shape parameters, our method additionally requires the subsequent changes in shape during the search to be smooth, which is achieved by using a minimum cost path search algorithm. We compare the two methods on a database of more than 400 manual segmentations of digital X-ray images of the femur, humerus and calcaneus. We evaluate the accuracy and robustness of both methods using a cross-validation procedure.
This paper describes a framework which aims at assisting the clinical analysis of temporal mammog... more This paper describes a framework which aims at assisting the clinical analysis of temporal mammograms. The framework exists of a processing part and a visualization part. The core components of the processing part are (1) an algorithm for spatial registration of two successive mammograms, (2) a method for automatic detection of Micro-Calcifications (MCs) and Micro-Calcification Clusters (MCCs) and, (3) an algorithm that allows an automatic identification of detected MCs and MCCs between two successive images. For the presentation of registration, detection and identification results, we present a visualization tool, called “Intelligent Synchronized Magnifying Glasses” (ISMAG), which allows a visualization of the results in an intuitive and non distracting way.
Computer Vision, Graphics, and Image Processing, 1985
... The whole matrixwas used as such.inen et al. [89] concluded that Laws' texture energy me... more ... The whole matrixwas used as such.inen et al. [89] concluded that Laws' texture energy measures based on 3 X 3 or 5 X 5 masks, are more powerful than measuresbased on pairs of pixels. Classification rates of over 80% were found. Harwood et al. ...
In this paper, we will review some visual inspection problems that were presented to our laborato... more In this paper, we will review some visual inspection problems that were presented to our laboratory by a consortium of Belgian industrial companies. These problems were selected to serve as a test vehicle for a software package, called LILY (Leuven Image processing Library), that was developed for the consortium by our laboratory. Therefore, this paper consists of several parts : first, an overview of the LILY software package will be given; then, three case studies carried out with the package will be detailed. The case studies are very different in nature, so that a variety of algorithms will be dealt with. The first case study is about defect inspection in unexposed radiographic film. In this case, image data is presented as a continuous stream of lines of pixels. In the study, convolution techniques, curve fitting methods and Fourier analysis were applied. The second case studv treats the inspection of textured textiles and is thus essentially a texture inspection problem. Here,...
Machine Intelligence and Pattern Recognition, 1988
In this paper we will present LILY, a software package for image processing. LILY stands for Leuv... more In this paper we will present LILY, a software package for image processing. LILY stands for Leuven Image processing LibrarY and has been developed with funding from a large number of Belgian industrial companies who are all interested in visual inspection problems. Therefore, the algorithms in the package are mainly concerned with this application field, although also other algorithms are incorporated. All procedures have been written in Pascal and Fortran on a VAX running VMS, with current work being done to convert the package to the C-language. Along with the programmed algorithms come a large number of support functions and procedures to facilitate the development of image processing programs. The package thus presents itself to the user as a large toolbox from which the appropriate tools must be taken to accomplish a certain task. The available procedures fall in one of the following categories: segmentation, coding, filtering, feature extraction, classification, texture analysis, relaxation, and pyramidal structures. In the first part of the paper, an overview will be given of the algorithms that are present in all these different classes. Syntactical conventions, documentation, maintenance and development tools will be discussed also. The second part of the paper is devoted to some specific problems that have been solved as a testcase for the algorithms. First Laws' procedure for texture segmentation is implemented and applied to the detection of defects in textiles. The procedure involves filtering the image with one or more suitably chosen masks, squaring the obtained values, computing the energy as a texture feature and classifying the resulting values. Each of these steps corresponds more or less to a different module of the package. A second industrial problem of defect inspection in unexposed radiographic film has been approached using three alternative techniques: one dimensional convolution filtering, Fourier domain filtering and polynomial regression.
Lee JS, Dewaele P., Wambacq P., Oosterlinck A., Jurkevich I., "Speckle filtering of syntheti... more Lee JS, Dewaele P., Wambacq P., Oosterlinck A., Jurkevich I., "Speckle filtering of synthetic aperture radar images : a review", Remote sensing reviews, vol. 8, pp. 313-340, 1994, Harwood Academic Publishers, USA. ... There are no files associated with this item. ... All items in Lirias are ...
... P. Dewaele, L. Van Gool, P. Wanibacq and A. Oosterlinck ... In a second section, we then desc... more ... P. Dewaele, L. Van Gool, P. Wanibacq and A. Oosterlinck ... In a second section, we then describe a novel approach, which how-ever clearly finds its roots in older work, especially by Ade [1,2] and Unser [9]. In a third and final part of the text we give some results on fabric ...
We propose an improved search procedure for Active Shape Model (ASM) based delineation of anatomi... more We propose an improved search procedure for Active Shape Model (ASM) based delineation of anatomical structures in digital X-ray images. Whereas the original ASM search method [1] iteratively improves the current estimate of the location of boundary points by a limited least squares adjustment of the pose and shape parameters, our method additionally requires the subsequent changes in shape during the search to be smooth, which is achieved by using a minimum cost path search algorithm. We compare the two methods on a database of more than 400 manual segmentations of digital X-ray images of the femur, humerus and calcaneus. We evaluate the accuracy and robustness of both methods using a cross-validation procedure.
This paper describes a framework which aims at assisting the clinical analysis of temporal mammog... more This paper describes a framework which aims at assisting the clinical analysis of temporal mammograms. The framework exists of a processing part and a visualization part. The core components of the processing part are (1) an algorithm for spatial registration of two successive mammograms, (2) a method for automatic detection of Micro-Calcifications (MCs) and Micro-Calcification Clusters (MCCs) and, (3) an algorithm that allows an automatic identification of detected MCs and MCCs between two successive images. For the presentation of registration, detection and identification results, we present a visualization tool, called “Intelligent Synchronized Magnifying Glasses” (ISMAG), which allows a visualization of the results in an intuitive and non distracting way.
Computer Vision, Graphics, and Image Processing, 1985
... The whole matrixwas used as such.inen et al. [89] concluded that Laws' texture energy me... more ... The whole matrixwas used as such.inen et al. [89] concluded that Laws' texture energy measures based on 3 X 3 or 5 X 5 masks, are more powerful than measuresbased on pairs of pixels. Classification rates of over 80% were found. Harwood et al. ...
In this paper, we will review some visual inspection problems that were presented to our laborato... more In this paper, we will review some visual inspection problems that were presented to our laboratory by a consortium of Belgian industrial companies. These problems were selected to serve as a test vehicle for a software package, called LILY (Leuven Image processing Library), that was developed for the consortium by our laboratory. Therefore, this paper consists of several parts : first, an overview of the LILY software package will be given; then, three case studies carried out with the package will be detailed. The case studies are very different in nature, so that a variety of algorithms will be dealt with. The first case study is about defect inspection in unexposed radiographic film. In this case, image data is presented as a continuous stream of lines of pixels. In the study, convolution techniques, curve fitting methods and Fourier analysis were applied. The second case studv treats the inspection of textured textiles and is thus essentially a texture inspection problem. Here,...
Machine Intelligence and Pattern Recognition, 1988
In this paper we will present LILY, a software package for image processing. LILY stands for Leuv... more In this paper we will present LILY, a software package for image processing. LILY stands for Leuven Image processing LibrarY and has been developed with funding from a large number of Belgian industrial companies who are all interested in visual inspection problems. Therefore, the algorithms in the package are mainly concerned with this application field, although also other algorithms are incorporated. All procedures have been written in Pascal and Fortran on a VAX running VMS, with current work being done to convert the package to the C-language. Along with the programmed algorithms come a large number of support functions and procedures to facilitate the development of image processing programs. The package thus presents itself to the user as a large toolbox from which the appropriate tools must be taken to accomplish a certain task. The available procedures fall in one of the following categories: segmentation, coding, filtering, feature extraction, classification, texture analysis, relaxation, and pyramidal structures. In the first part of the paper, an overview will be given of the algorithms that are present in all these different classes. Syntactical conventions, documentation, maintenance and development tools will be discussed also. The second part of the paper is devoted to some specific problems that have been solved as a testcase for the algorithms. First Laws' procedure for texture segmentation is implemented and applied to the detection of defects in textiles. The procedure involves filtering the image with one or more suitably chosen masks, squaring the obtained values, computing the energy as a texture feature and classifying the resulting values. Each of these steps corresponds more or less to a different module of the package. A second industrial problem of defect inspection in unexposed radiographic film has been approached using three alternative techniques: one dimensional convolution filtering, Fourier domain filtering and polynomial regression.
Lee JS, Dewaele P., Wambacq P., Oosterlinck A., Jurkevich I., "Speckle filtering of syntheti... more Lee JS, Dewaele P., Wambacq P., Oosterlinck A., Jurkevich I., "Speckle filtering of synthetic aperture radar images : a review", Remote sensing reviews, vol. 8, pp. 313-340, 1994, Harwood Academic Publishers, USA. ... There are no files associated with this item. ... All items in Lirias are ...
... P. Dewaele, L. Van Gool, P. Wanibacq and A. Oosterlinck ... In a second section, we then desc... more ... P. Dewaele, L. Van Gool, P. Wanibacq and A. Oosterlinck ... In a second section, we then describe a novel approach, which how-ever clearly finds its roots in older work, especially by Ade [1,2] and Unser [9]. In a third and final part of the text we give some results on fabric ...
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