The aim of this study is to present research made in a 3d scanner conception of a human foot. The first step of foot reconstruction is treated. The cloud number points is increased thanks to a combination of several m...
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The aim of this study is to present research made in a 3d scanner conception of a human foot. The first step of foot reconstruction is treated. The cloud number points is increased thanks to a combination of several methods. The first method for the first points extraction is explained. The relative length, height and width of the object are obtained in order to construct the parallelepiped including the foot. All parallelepiped points are virtually assigned to foot points. Each image is projected in the volume in the different planes of the views in order to eliminate the exterior points. From the volume of all these points only the points of the surface are retained. The points of the cloud should be located on or outside the surface of the foot. This reconstruction must be ameliorated by an active triangulation. We use the tools of matching points of stereovision in the image profiles.
Summary form only given. Several closely related methods have been proposed in recent years to smooth, denoise, edit, compress, transmit, and animate very large polygon meshes, based on topological and combinatorial m...
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Summary form only given. Several closely related methods have been proposed in recent years to smooth, denoise, edit, compress, transmit, and animate very large polygon meshes, based on topological and combinatorial methods, signal processing techniques, constrained energy minimization, and the solution of diffusion differential equations. In particular, polygon models, which are used in most graphics applications, require considerable amounts of storage, even when they only approximate precise shapes with limited accuracy. To support the Internet access to 3d models of complex virtual environments or assemblies for electronic shopping, collaborative CAd, multi-player video games, scientific visualization, representations of 3d shapes must be compressed by several orders of magnitude. The author provides a quick overview of the mesh signal processing approach. Then he describes in more detail some recent results and applications: linear anisotropic mesh filtering, bi-level isosurface compression, and space-optimized texture maps.
Because of the convenience of a text-based format 3d content is often published in the form of a gzipped file that contains an ASCII description of the scene graph. While compressed image, audio, and video data is kep...
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Because of the convenience of a text-based format 3d content is often published in the form of a gzipped file that contains an ASCII description of the scene graph. While compressed image, audio, and video data is kept in separate binary files, polygon meshes and interpolators are usually included uncompressed into the ASCII description, as there is no widely-accepted standard for such data. We show how to use compressed polygon meshes and compressed interpolators within a purely text-based format. Our scheme codes these data-heavy nodes as ASCII strings that compress well with standard gzip compression. Specifically we demonstrate the efficiency of this technique on a sparse scene composed of many small polygon meshes. While typical for 3d content on the Web, such scenes tend to be more difficult to compress.
The complexity of triangle meshes is growing rapidly due to the need for higher accuracy. As a consequence, the network transmissiondelay of 3d graphics data is the major bottleneck in computer graphics. An interesti...
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The complexity of triangle meshes is growing rapidly due to the need for higher accuracy. As a consequence, the network transmissiondelay of 3d graphics data is the major bottleneck in computer graphics. An interesting solution to this limited bandwidth is the compression technique. This solution implies the necessity of specific hardware to reconstruct the mesh at the entrance of the graphics pipeline. In this work we present a new compression connectivity algorithm for triangle meshes. This is a simple algorithm which improves the compression ratio (nearly 1.5 bits/triangle) by previously reported schemes. due to its simplicity, it is very suitable for hardware implementation. This implementation has a simple and efficient structure, low storage requirements and a reconstruction rate of one triangle per cycle.
In this paper we present a three-dimensional model retrieval system. In our approach, a three-dimensional model is described by three invariant descriptors: a curvature index which consists of a histogram of the princ...
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In this paper we present a three-dimensional model retrieval system. In our approach, a three-dimensional model is described by three invariant descriptors: a curvature index which consists of a histogram of the principal curvatures of each face of the mesh, a histogram of distances between the faces, and a histogram of the volumes based on each face. This work focuses on extracting these invariant descriptors from the three-dimensional models, and on combining these descriptors in order to improve retrieval performance. An experimental evaluation demonstrates the satisfactory performance of our approach on a fifty three-dimensional model database.
The use of robots for fault diagnosis and maintenance operations is being more widely used. Robot control is generally done by teleoperation, which still has many weak points. To solve these problems, we use virtual r...
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The use of robots for fault diagnosis and maintenance operations is being more widely used. Robot control is generally done by teleoperation, which still has many weak points. To solve these problems, we use virtual reality techniques. We conceive a system for collecting vibration data using remote robot control by a virtual designed model. With our model we can manipulate both the machine to be checked, and the robot. In our 3d model the data collection points are very well known. This will assure precision in data collection. Our system assure good remote maintenance and fault diagnosis not only in dangerous places, but also in ordinary cases.
A method for reconstructing 3d rational B-spline surfaces from multiple views is proposed. Given corresponding features in multiple views, though not necessarily visible in all views, the surface is reconstructed. Fir...
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A method for reconstructing 3d rational B-spline surfaces from multiple views is proposed. Given corresponding features in multiple views, though not necessarily visible in all views, the surface is reconstructed. First 2d B-spline patches are fitted to each view. The 3d B-spline and projection matrices can then be extracted from the 2d B-splines using factorization methods. The surface fit is then further refined via an iterative procedure. Finally, a hierarchal fitting scheme is proposed to allow modeling of complex surfaces by means of knot insertion. Experiments with real imagery demonstrate the efficacy of the approach.
Recent developments in 3d technologies and measurement instrumentation combined with multimedia databases offer today new possibilities for the integrated and complete description of cultural heritage objects. A first...
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Recent developments in 3d technologies and measurement instrumentation combined with multimedia databases offer today new possibilities for the integrated and complete description of cultural heritage objects. A first attempt is made to develop a database for archaeological ceramic and glass artifacts where in addition to the digitized 2d and3d images, description, typological characteristics and historical information for each artifact will also include point-wise surface data. In a pilot implementation, physicochemical data mapped on the surface of the 3ddigital image of the object will be included. Thus, the researcher will have the entire information regarding the specific artifact at his disposal. This information will contribute significantly to the comparative study of artifacts, provenance studies, determination of weathering, authentication anddetection of forgery, inspection of past restorations etc.
Inpainting refers to the task of filling in missing or damaged regions of an image. In this paper we are interested in the inpainting problem where the missing regions are so large that local inpainting methods fail. ...
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Inpainting refers to the task of filling in missing or damaged regions of an image. In this paper we are interested in the inpainting problem where the missing regions are so large that local inpainting methods fail. As an alternative to the local principle, we make use of other images with related global information to enable a reasonable inpainting. Our method has roughly three phases: landmark matching, interpolation, and copying. The experimental results obtained are promising.
A family of high-performance 3d imaging laser sensors are presented providing rapid acquisition of 3ddata of naturally reflecting objects within a wide field-of-view and with ranges up to 1000 meters. Beside the basi...
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A family of high-performance 3d imaging laser sensors are presented providing rapid acquisition of 3ddata of naturally reflecting objects within a wide field-of-view and with ranges up to 1000 meters. Beside the basic 3d-information the sensors also supply, pixel for pixel, true color information gained by an additional passive channel. This color information allows an instantaneous automatic texturing of 3d models. The sensors are of a rugged and compact design and can thus be used even under adverse environmental conditions. Potential applications include scene acquisition for virtual reality modeling, 3d-imaging of large buildings in the field of architecture, topographic mapping anddimensional measurements of vessels, furnaces, tanks, etc. The sensor makes use of high-speed laser ranging based on the time-of-flight method using a pulsed laser source in combination with precise mechanical scanning of the measuring beam. data are provided at a standard parallel interface allowing easy integration with any standard PC based system for datavisualization anddataprocessing. These data are provided with an average data rate up to 18000 measurements per second. Examples of data acquired with the sensors are presented, accuracy and ranging capability are discussed.
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