ArcEngine开发总结-（3）栅格平滑

行业应用中，插值得到的栅格图不是很美观，可以平滑去掉栅格小斑块以达到美观。对应arcmap中的focal statistics功能，基本原理是利用计算周围范围内的栅格标准差为最终栅格值，达到栅格的平滑效果。栅格范围 可以是矩形  圆形、环状、扇形、及其他高级形状（可查相关资料），以下程序提供 圆形范围平滑及利用递归实现设置平滑次数

  

/// <summary>
    /// 模块编号：RasterSmooth
    /// 作用：栅格平滑
    /// 作者
    /// 编写日期：2011-07-11
    /// </summary>
    class RasterSmooth
    {
        private IGeoDataset geoDataset;
        private IRasterNeighborhood rasterNeighborhood;
        private INeighborhoodOp neighborhoodOp;
        private IRaster outRaster=null;
        private int num;

        /// <summary>
        /// 栅格平滑
        /// </summary>
        /// <param name="raster">栅格</param>
        /// <param name="width">象元数</param>
        /// <param name="height">象元数</param>
        /// <returns></returns>
        public IRaster Smooth(IRaster raster,double width,int smooths)
        {
            num=smooths;
            if(raster!=null)
            {
                geoDataset = raster as IGeoDataset;

                rasterNeighborhood = new RasterNeighborhoodClass();

                rasterNeighborhood.SetCircle(width, esriGeoAnalysisUnitsEnum.esriUnitsCells);

                neighborhoodOp = new RasterNeighborhoodOpClass();
           
                if (num > 0)
                {
                    outRaster = neighborhoodOp.FocalStatistics(geoDataset, esriGeoAnalysisStatisticsEnum.esriGeoAnalysisStatsMean, rasterNeighborhood, true) as IRaster;
                    num = num - 1;
                    outRaster = Smooth(outRaster, width, num);
                }
            }
            return outRaster;
        }
    }