等值线在地学中是最常用的图形描述方法之一,等值线的形式可以直观地显示数据的空间分布和变化特征,等高线就是一种描述地形高度的等值线图。可以从两个方面讨论等值线,一个方面是结合图像处理、模式识别等理论技术,从等高线版图提取DEM模型;另一方面是基于网格模型,经过等值线追踪、等值线内插等处理技术产生等值线图。 Isolines are one of the most commonly used methods of graph description in geosciences. In the form of contour lines, the spatial distribution and variation characteristics of data can be visually displayed. Contour is a contour map describing the height of the terrain. The isoline can be discussed from two aspects. One is the combination of image processing, pattern recognition and other theoretical techniques to extract the DEM model from the contour map. On the other hand, based on the grid model, after the contour tracing, Interpolation and other processing techniques produce contour plots.