| 摘要 |
Cartographic data is represented using wavelet coefficients. Specifically, a cartographic shape point database consisting of shape points and nodes stored on a per geographic feature basis is converted to a cartographic wavelet database consisting of wavelet and scaling coefficients also stored on a per geographic feature basis. The shape of each geographic feature can be reconstructed from the stored wavelet and scaling coefficients for that geographic feature. The wavelet transform organizes the information in a function according to scale, a concept which is related to resolution. The wavelet-based representation facilitates operations such as line simplification (generalization) and zooming. Multi-resolution error metrics are defined using the wavelet representation for assessing the accuracy of sampled cartographic databases with respect to a ground truth database.
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