Research On 3D Visualization Of High-dimensional Images Based On Virtual Earth

The three-dimensional visualization of remote sensing images based on Virtual Earth is beneficial to display image information to the general-publication and brings great convenience to entertainment,education,scientific exploration and other work.What's more,the three-dimensional visualization of images provides a wonderful platform for scientific researchers to display their achievements and who can use it to display the work such as climate change,spatial GIS analysis and so on.However,at present,the three-dimensional visualization of remote sensing images based on Virtual Earth usually neglects the multi-band characteristics of remote sensing images,and only three bands are selected for visualization.This method will restrict the transmission of image information to a certain extent,on the other hand,the dynamic expression ability of images is limited.In view of these limitations in the current three-dimensional visualization methods of remote sensing images,this paper designs and implements a dynamic threedimensional visualization method for high-dimensional images.The method is not limited the number of image bands and is suitable for remote sensing image data with multi-band characteristics.In this paper,the high-dimensional remote sensing image data is treated as a 3D cube data processing.The three dimensions correspond to the length,width and band number respectively.When image visualization is realized on virtual earth,on the one hand,users can observe the three-dimensional image scene without obstacle from any angle of observation,on the other hand,the band of image can also be switch at will based on the users' wishes.The main work and contributions of this paper are as follows:(1)In order to use the underlying terrain tile data,this paper first designs and implements an irregular degenerated quadtree data model organization method.On the one hand,it can directly use the existing terrain tile data and avoid the problem of repeated calculation and terrain interpolation.On the other hand,it can effectively avoid the problem of computing redundancy of nodes in blank areas for irregular image visualization.Then,aiming at the problem of band switching,this paper adopts the method of data band-by-band storage and block management,and adopts the linear list storage mode to control the size of data storage files,effectively improve the band switching efficiency and accelerate the model scheduling efficiency.Finally,the model organization method is tested to verify the feasibility and efficiency of the algorithm.(2)Aiming at the scheduling efficiency of data model,this paper firstly designs and implements a data two-level buffer mode,which adds a second-level buffer of image band switching scheme to the node one-level buffer,and effectively solves the problem of repeated reading of band switching data.On this basis,this paper designs and implements a view cone clipping method based on the angle between observation line of sight and tile normal.It greatly improves the efficiency of clipping,further accelerates the efficiency of data scheduling,and finally effectively solves the scene carton problem in band switching.(3)The band switching method of high-dimensional image visualization is closely related to the effect of visual information expression.In order to achieve a good effect of multi-dimensional dynamic visualization of remote sensing images,this paper designs and implements a variety of band combination typical visualization modes.According to different application scenarios,the design of visualization mode can be divided into static mode and dynamic mode.Static mode is mainly aimed at maximizing the difference between objects in image interpretation,and dynamic mode is aimed at the visualization of time series transformation image and the effect of image animation.This method reserves an interface for the visualization mode to be designed on demand.The typical design mode only considers the common scene of image visualization.The dynamic visualization method of multi-band remote sensing image implemented in this paper realizes the 4D visualization mode of image.The image data is processed in the form of 3D cube,and different bands are displayed dynamically with time change.The animation effect of image is realized by using visual continuity.The method of dynamic three-dimensional visualization of image realizes the transformation from static space display mode to multi-dimensional dynamic space."Multidimensionality" is embodied in the multi-dimensional image band and display mode,and the dynamic is embodied in the interaction between users and threedimensional scenes.