基于地形高度域的数据压缩算法研究

Research on Terrain Height Field Compression Algorithm

随着遥感技术的发展,地形数据规模越来越大,远远超过了内存处理的范围,成为急需解决的问题.通过数据压缩提高系统吞吐量是常用技术之一,随着GPU技术的快速发展,传统的压缩算法无法充分利用GPU的能力.鉴于此,本文提出了一种基于GPU的地形数据压缩方法,实现了高度域和位置信息的压缩.不同于其他的算法仅对高度或位置进行压缩,本文的主要贡献在于将地形的位置和高度同时进行处理,当前顶点的所有信息都可以根据当前分段计算得到.算法对地形的高度域进行贝塞尔曲线的近似,保存每个顶点的差值,实现有损和无损的相结合的高比率的压缩.通过与传统方法的比较,实验结果表明,能够取得很好的压缩效果.

With the development of remote sensing technology, the size of terrain is growing rapidly, and far beyond the scope of main memory, has become an urgent problem. Data compression is a popular technology to increase system throughput. With the rapid development of GPU （ Graphics Processing Unit） technology, the traditional compression algo- rithms cannot take full advantage of the ability of the current GPU. In this paper, we propose a GPU-based terrain data com- pression method, and achieve a high rate compression of terrain height field and location. Comparing to other algorithms, the main contribution of our algorithm is that the compression of terrain height filed and position is executed in the same time, and all the information of a node can be calculated according to the presentstrip. For terrain height domain, we firstly make Bezier curve approximation, then save the difference. After the steps above, we can achieve high compression ratio. By com- parison with traditional methods, we get reasonable experimental results.