In the German Authoritative Topographic Cartographic Information System (ATKIS), the 2d positions and the heights of objects such as roads are stored separately in the digital landscape model (dLM) anddigital terrain...
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In the German Authoritative Topographic Cartographic Information System (ATKIS), the 2d positions and the heights of objects such as roads are stored separately in the digital landscape model (dLM) anddigital terrain model (dTM), which is often acquired by airborne laser scanning (ALS). However, an increasing number of applications require a combinedprocessing andvisualization of these two data sets. due to different kinds of acquisition, processing, and modelling discrepancies exist between the dTM anddLM and thus a simple integration may lead to semantically incorrect 3d objects. For example, roads may be situated on strongly tilteddTM parts and rivers sometimes flow uphill. In this paper we propose an algorithm for the adaptation of 2d road centrelines to ALS data by means of network snakes. Generally, the image energy for the snakes is defined based on ALS intensity and height information andderived products. Additionally, buildings and bridges as strong features in height data are exploited in order to support the road adaptation process. Extracted buildings as priors modified by a distance transform are used to create a force of repulsion for the road vectors integrated in the image energy. In contrast, bridges give strong evidence for the correct road position in the height data. Therefore, the image energy is adapted for the bridge points. For that purpose bridge detection in the dTM is performed starting from an approximate position using template matching. Examples are given which apply the concept of network-snakes with new image energy for the adaptation of road networks to ALS data taking advantage of the prior known topology.
High density elevation data like Light detection And Ranging (LidAR) has been gaining popularity as the preferred high resolution digital surface model for 3dvisualization, analysis and integration with other remotel...
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High density elevation data like Light detection And Ranging (LidAR) has been gaining popularity as the preferred high resolution digital surface model for 3dvisualization, analysis and integration with other remotely senseddata. At Valtus we have been delivering elevation data in various formats for the oil and gas, environmental and infrastructure industries from our extensive online library encompassing Alberta and it surrounding provinces. The elevation data acquired by leading aerial providers has a high degree of accuracy and has been instrumental in our customers' spatial analysis andvisualization needs. We have been using the online delivery mechanism of our spatial data store to allow users to securely search, clip to a given area of interest anddownload raw datasets (bare and full earth) in various formats and projections. Our customers have then taken these raw datasets and ingested them into different desktop applications for exploitation. However, our customer survey for improvements revealed that even though the datasets were being used in multiple GIS applications, the majority of the users only needed a handful of value added products like shaded relief and contours generated from these raw datasets. This usage trend has created an unnecessary burden on few geospatial experts not only in preparing the data for intake to different applications, but producing anddisseminating these products to the non GIS users within their organizations. The major finding of the survey was, will it be possible to stream these value added products directly to the non GIS user's application instead of going through a multi-step workflow. Valtus has already developed very sophisticated and streamlined terrain processing modules that provide support for automatically creating different kinds of products, which include tiled point clouds, contours, elevation grids, shaded reliefs, intensity/data void images, accuracy analysis and evaluation reports anddifferent metad
The three-dimensional rendering of microscopic objects is a difficult and challenging task that often requires specialized image processing techniques. Previous work has been described of a semi-automatic segmentation...
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ISBN:
(纸本)9781617384721
The three-dimensional rendering of microscopic objects is a difficult and challenging task that often requires specialized image processing techniques. Previous work has been described of a semi-automatic segmentation process of fluorescently stained neurons collected as a sequence of slice images with a confocal laser scanning microscope. Once properly segmented, each individual object can be rendered and studied as a three-dimensional virtual object. This paper describes the work associated with the design anddevelopment of Matlab files to create three-dimensional images from the segmented object data previously mentioned. Part of the motivation for this work is to integrate both the segmentation and rendering processes into one software application, providing a seamless transition from the segmentation tasks to the rendering andvisualization tasks. Previously these tasks were accomplished on two different computer systems, windows and Linux. This transition basically limits the usefulness of the segmentation and rendering applications to those who have both computer systems readily available. The focus of this work is to create custom Matlab image processing algorithms for object rendering andvisualization, and merge these capabilities to the Matlab files that were developed especially for the image segmentation task. The completed Matlab application will contain both the segmentation and rendering processes in a single graphical user interface, or GUI. This process for rendering three-dimensional images in Matlab requires that a sequence of two-dimensional binary images, representing a cross-sectional slice of the object, be reassembled in a 3d space, and covered with a surface. Additional segmented objects can be rendered in the same 3d space. The surface properties of each object can be varied by the user to aid in the study and analysis of the objects. This inter-active process becomes a powerful visual tool to study and understand microscopic objects.
High resolution multichannel ECG measurement is necessary prerequisite for advanceddiagnostics of various cardiovascular diseases. Special multichannel electrocardiograph ProCardio-8 was developed to obtain ECG signa...
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ISBN:
(纸本)9781617823381
High resolution multichannel ECG measurement is necessary prerequisite for advanceddiagnostics of various cardiovascular diseases. Special multichannel electrocardiograph ProCardio-8 was developed to obtain ECG signals with desired quality. The system is conceived as a virtual instrument with an external intelligent measuring unit connected to a host PC running dedicated application software. In this paper, the data acquisition software developed in MATLAB version 7 and using the Signal processing Toolbox is introduced. In the first part of the paper, applicability of MATLAB for fast data acquisition was verified anddata throughput between the measuring unit and the PC was estimated using a data source with adjustable data rate. Second part of the paper is devoted to development and optimization of a measuring software module that includes control of the measuring unit, testing of electrode contacts and real time data acquisition, visualization and storage of measureddata.
With the acceleration of urbanization, the phenomenon of urban drinking water pollution is quite obvious. According to China Environmental State Bulletin, the national surface water quality in general is moderately po...
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ISBN:
(纸本)9781424473021
With the acceleration of urbanization, the phenomenon of urban drinking water pollution is quite obvious. According to China Environmental State Bulletin, the national surface water quality in general is moderately polluted in 2006. In the National Environmental Monitoring Network, the actual monitoring sections of the 745 surface water monitoring sections (the river sections 593, lake and reservoir point positions 152), I similar to III class, IV, V class, inferior class V cross-section of the water quality of the respective ratios is 40%, 32% and 28%. The major pollution indicators are permanganate index, ammonia nitrogen and oil and so on. While developed countries have reached the international advanced level in drinking water quality standards, issued a series of laws and regulations to improve water quality, planning programs, and has taken a number of the corresponding technical support measures, but in water quality information management and monitoring of early warning still remains more problems. From the quality of drinking water collection, transmission, conversion to store, manage, display, analysis and early warning, we can draw a series of research results to provide a method to effectively solve the water quality control early-warning data upload is not timely, large error, management difficulties, the expression single issues such as the lack of analytical tools, and construct a set of water quality from source to faucet monitoring system, the formation of urban drinking water quality management, analysis, monitoring, early warning and related technology research anddevelopment integrated platform for experts providers, governments at all levels of scientific decision making and timely day to day management of technical support to the Chief. Based on water quality monitoring network and a distributed, network-based, multi-source water quality information collection technology, transmission technology, processing technology, visualization technology
A channel estimation algorithm for MIMO-OFdM systems in Fast Time-Varying Environments is proposed. The channel estimation function is based on the equivalent discrete-time channel taps or on the physical propagation ...
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Hyperspectral image consist of a set of contiguous images bands collected by a hyperspectral sensor. The large amount of data of hyperspectral images emphasizes the importance of efficient compression for storage and ...
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Hyperspectral image consist of a set of contiguous images bands collected by a hyperspectral sensor. The large amount of data of hyperspectral images emphasizes the importance of efficient compression for storage andtransmission. This paper proposes the simplified version of the three dimensional Set Partitioning Embedded bloCK (3d SPECK) algorithm for lossy compression of hyperspectral image. A three dimensional discrete wavelet transform (3ddWT) can fully exploit the interband correlation in a volumetric block. This provides the obvious way to process data such as with hyperspectral images. The 3d structure of the SPECK algorithm will suitably extend the exploitation of interbanddependence and correlation. The proposed algorithm maintains the 3d SPECK algorithm with modification of the implementation without using any list to store the significant information. This would reduce the memory requirement of the embedded coding algorithm and improve the coding time to compress the images.
Traditional 3d watermarking mostly applies offline decode, which usually requires a complete 3d mesh. For a set of level-of-detail(LOd) meshes, the watermark has to be robust enough to survive from LOd generation algo...
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ISBN:
(纸本)9781424444618
Traditional 3d watermarking mostly applies offline decode, which usually requires a complete 3d mesh. For a set of level-of-detail(LOd) meshes, the watermark has to be robust enough to survive from LOd generation algorithms that applies mesh simplification; otherwise, they may have to embed the watermark into each LOd mesh individually. To cope with such problems, we proposed a novel 3d mesh watermarking approach on the basis of the progressive mesh and the discrete wavelet transform. The new approach begins with mutiresolution processing of the cover object and the watermark respectively by a progressive mesh encoder and a Haar-baseddiscrete wavelet transform encoder. By embedding the transformed sequence of the watermark image into the vertex split sequence of the progressive mesh, the watermark and the cover object are transmitted synchronously such that the progressive decode of the cover object and the extraction anddecoding of the watermark can be performed on-the-fly with the transmission. Once if the transmission is interrupted, it is still possible to verify the watermark for it is progressively displayed along with the cover object.
VRGIS is a production of combining Geographic Information System with virtual reality technology, and it is also a research hotspot in this two areas. However, the real-time features for Virtual Reality Geographic Inf...
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VRGIS is a production of combining Geographic Information System with virtual reality technology, and it is also a research hotspot in this two areas. However, the real-time features for Virtual Reality Geographic Information System have been seriously hindered in the development of practical application and popularization. If we simply add fog particles into the 3d Geographic Information System scene directly as used in virtual reality field, the realtime effect of fog rendering can't easily obtained. Therefore, a fog visualization algorithm in 3d GIS is presented which bases on image processing method, and the results show that realistic fog scenes are achieved with few time cost.
Since real-time acquisition of 3d echocardiographic data is achievable in practice, many volume rendering algorithms have been proposed for visualization purposes. However, due to the large amounts of data and computa...
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Since real-time acquisition of 3d echocardiographic data is achievable in practice, many volume rendering algorithms have been proposed for visualization purposes. However, due to the large amounts of data and computations involved a trade-off between image quality and computational efficiency has to be made. The main goal of our study was to generate high quality volume renderings in real-time, by implementing pre-processing and ray-casting algorithms directly on the GPU. Furthermore the advantage of combining a-priori anatomic and functional information with the volume rendered image was also investigated. The proposed algorithms were implemented both in CUdA and OpenCL and validated on patient datasets acquired using a GE Vivid7 dimensions system. Assuming a 512×512 pixels output resolution, average running times of 4.2 ms/frame are achievable on high-end graphics systems. Furthermore a good correspondence between wall thickening and segmental longitudinal strain values was visually observed. By implementing ray-casting on the GPU, the overall processing time is significantly reduced, thus making real-time interactive 3d volume rendering feasible. Combining anatomical and functional information allows for a quick visual assessment of a given case.
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