地形数据的空间自相关性有着很强的方向属性。为了充分地利用这一属性来消除地形数据之间的信息冗余度,本文提出了一种自适应分块的编码方法。首先确定地形带的自相关方向属性,然后依照地形方向性的不同,将数据按不同矩形形状进行方块划分,然后对较平坦的地形块和剧烈变化的地形块分别采用MVQ方法和BTC-VQ方法进行编码,以保护边缘信息。这种采用自适应分块方式的编码方法与通常使用的固定分块方式的编码方法相比,可以大大降低编码的失真度。 Spatial autocorrelation of terrain data has strong directional properties. In order to make full use of this property to eliminate the redundancy of information between topographic data, an adaptive coding method is proposed in this paper. Firstly, the autocorrelation properties of the terrain belts are determined. Then, the data are divided into different rectangular shapes according to the difference of the terrain direction. Then the MVQ method and the BTC-VQ method are used for the flat terrain blocks and the drastically changing terrain blocks Encoding to protect the edge information. Compared with the commonly used fixed block coding method, the coding method using adaptive block coding method can greatly reduce the coding distortion.