Converting Elevation Contours to a Grid
نویسندگان
چکیده
We present two new methods for approximating elevation data from contours to a grid. The first repeatedly interpolates new contour lines between the original ones. The second starts with any interpolated or approximated surface, determines its gradient lines, and does a Catmull-Rom spline interpolation along them to improve the elevations. We compare the new methods to a more classical thin-plate approximation on various data sets. The new methods appear visually smoother, with the undesirable terracing effect much reduced.
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