This paper describes a method based on an energy minimizing deformable model applied to the 3D biomechanical modeling of a set of organs considered as regions of interest (ROI) for radiotherapy. The initial model cons...This paper describes a method based on an energy minimizing deformable model applied to the 3D biomechanical modeling of a set of organs considered as regions of interest (ROI) for radiotherapy. The initial model consists of a quadratic surface that is deformed to the exact contour of the ROI by means of the physical properties of a mass-spring system. The exact contour of each ROI is first obtained using a geodesic active contour model. The ROI is then parameterized by the vibration modes resulting from the deformation process. Once each structure has been defined, the method provides a 3D global model including the whole set of ROIs. This model allows one to describe statistically the most significant variations among its structures. Statistical ROI variations among a set of patients or through time can be analyzed. Experimental results are presented using the pelvic zone to simulate anatomical variations among structures and its application in radiotherapy treatment planning.展开更多
The widespread availability of portable computing power and inexpensive digital cameras are opening up new possibilities for retailers in some markets. One example is in optical shops,where a number of systems exist t...The widespread availability of portable computing power and inexpensive digital cameras are opening up new possibilities for retailers in some markets. One example is in optical shops,where a number of systems exist that facilitate eyeglassess election. These systems are now more necessary as the market is saturated with an increasingly complex array of lenses,frames,coatings,tints,photochromic and polarizing treatments,etc. Research challenges encompass Computer Vision,Multimedia andHuman-Computer Interaction. Cost factors are also of importance for widespread product acceptance. This paper describes alow-cost system that allows the user to visualize different glasses models in live video. The user can also move the glasses toadjust its position on the face. The system,which runs at 9.5 frames/s on general-purpose hardware,has a homeostatic modulethat keeps image parameters controlled. This is achieved by using a camera with motorized zoom,iris,white balance,etc. Thisfeature can be specially useful in environments with changing illumination and shadows,like in an optical shop. The system alsoincludes a face and eye detection module and a glasses management module.展开更多
基金Project partially supported by the VI FP and VII FP of the European Commission through MAESTRO and ENVISIONprojects (Nos. IP CE503564 and SP CE241851)Spanish Junta de Comunidades de Castilla–La Mancha (Nos. PBC06-0019 and PI-2006/01.1)
文摘This paper describes a method based on an energy minimizing deformable model applied to the 3D biomechanical modeling of a set of organs considered as regions of interest (ROI) for radiotherapy. The initial model consists of a quadratic surface that is deformed to the exact contour of the ROI by means of the physical properties of a mass-spring system. The exact contour of each ROI is first obtained using a geodesic active contour model. The ROI is then parameterized by the vibration modes resulting from the deformation process. Once each structure has been defined, the method provides a 3D global model including the whole set of ROIs. This model allows one to describe statistically the most significant variations among its structures. Statistical ROI variations among a set of patients or through time can be analyzed. Experimental results are presented using the pelvic zone to simulate anatomical variations among structures and its application in radiotherapy treatment planning.
文摘The widespread availability of portable computing power and inexpensive digital cameras are opening up new possibilities for retailers in some markets. One example is in optical shops,where a number of systems exist that facilitate eyeglassess election. These systems are now more necessary as the market is saturated with an increasingly complex array of lenses,frames,coatings,tints,photochromic and polarizing treatments,etc. Research challenges encompass Computer Vision,Multimedia andHuman-Computer Interaction. Cost factors are also of importance for widespread product acceptance. This paper describes alow-cost system that allows the user to visualize different glasses models in live video. The user can also move the glasses toadjust its position on the face. The system,which runs at 9.5 frames/s on general-purpose hardware,has a homeostatic modulethat keeps image parameters controlled. This is achieved by using a camera with motorized zoom,iris,white balance,etc. Thisfeature can be specially useful in environments with changing illumination and shadows,like in an optical shop. The system alsoincludes a face and eye detection module and a glasses management module.
