Dimension setting method based on vector data traffic

Abstract

Disclosed is a scale setting method based on the vector data information content; the scale setting method is the scale sequence computing method which considers the spatial distribution features of the information content; the multi-scale vector database generated on the basis of the sequence has the advantages of rapid network distribution speed and small data redundancy degree; the method includes the steps: (1) the information content index which has positive correlation with the system running time is searched; the information content corresponding to the information content index is searched out and used as the threshold value according to the requirement on the running time from the user. (2) The window display scale is initialized. (3) the spatial distribution map is generated andthe complex region is selected according to the selected information content index; the center of the window is moved to the center of the complex region while the window display scale is increased gradually; if the window information content is not less than the threshold value in step 1, the current window display scale is added to the scale sequence; under the current window scale, the vector data is integrated; the integrated result is inputted to the step 3 for repeated execution until the coverage area of the window is larger than or equal to the coverage area of the vector data.

Description

technical field [0001] The invention relates to a scale setting method based on the amount of vector data information, which is used for the generation of key scale sequences of multi-scale vector databases in projects such as rapid release of massive spatial information networks, gradual transmission of mobile terminal spatial data in field operations, and the like. Background technique [0002] With the continuous expansion and deepening of GIS applications in various fields, especially the development of "digital earth" and Internet technology, the contradiction between limited national spatial infrastructure and unlimited massive spatial information services has become increasingly acute, and there is an urgent need for GIS output. Spatial data automatically increases or decreases the amount of information as the scale changes, that is, the multi-scale expression and visualization of spatial data. [0003] In recent years, with wavelet compression and image pyramid model...

AI Technical Summary

Problems solved by technology

If there are too many scales, the smoothness of the transition between scales will be improved, but it will also increase the data redundancy and reduce the operating efficiency of the system; The transition between

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