克里金插值算法java

克里金插值算法（Kriging Interpolation）是一种用于空间插值的经典算法。在Java语言中，可以使用GeoTools库中的KrigingInterpolator类来实现克里金插值算法。

下面是一个简单的克里金插值算法示例代码：

import org.geotools.coverage.grid.GridCoverage2D;
import org.geotools.coverage.grid.io.GridCoverage2DReader;
import org.geotools.gce.arcgrid.ArcGridReader;

import org.geotools.factory.CommonFactoryFinder;
import org.geotools.geometry.jts.ReferencedEnvelope;
import org.geotools.referencing.CRS;
import org.geotools.referencing.crs.DefaultGeographicCRS;
import org.opengis.coverage.grid.GridCoordinates;
import org.opengis.coverage.grid.GridGeometry;
import org.opengis.coverage.grid.GridSampleDimension;
import org.opengis.geometry.Envelope;
import org.opengis.parameter.ParameterValueGroup;
import org.opengis.referencing.crs.CoordinateReferenceSystem;

import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import javax.media.jai.JAI;
import javax.media.jai.RenderedOp;

import org.geotools.coverage.grid.GridCoverageFactory;
import org.geotools.coverage.grid.GridCoverageFactoryFinder;
import org.geotools.coverage.grid.Interpolator2D;
import org.geotools.coverage.grid.io.GridFormatFinder;
import org.geotools.coverage.grid.io.GridFormatFinderSpi;
import org.geotools.coverage.processing.CoverageProcessor;
import org.geotools.coverage.processing.operation.Interpolation;
import org.geotools.data.DataUtilities;
import org.geotools.factory.Hints;
import org.geotools.geometry.DirectPosition2D;
import org.geotools.geometry.jts.JTSFactoryFinder;
import org.geotools.process.raster.InterpolationProcess;
import org.geotools.process.raster.KernelFactory;
import org.geotools.process.raster.RasterFactory;
import org.geotools.process.raster.RasterFormat;
import org.geotools.process.raster.RasterProcess;
import org.geotools.process.raster.Warp;
import org.geotools.process.raster.WarpBuilder;
import org.geotools.process.raster.WarpFactory;
import org.geotools.process.raster.WarpFactoryFinder;
import org.geotools.process.raster.ZonalStats;
import org.geotools.process.raster.ZonalStatsProcess;
import org.geotools.process.vector.IntersectionFeatureCollection;
import org.geotools.process.vector.VectorToRasterProcess;
import org.geotools.process.vector.VectorToRasterProcessFactory;
import org.geotools.referencing.ReferencingFactoryFinder;
import org.geotools.referencing.operation.DefaultCoordinateOperationFactory;
import org.geotools.referencing.operation.transform.ProjectiveTransform;
import org.geotools.resample.ResampleProcess;
import org.geotools.util.factory.FactoryRegistryException;
import org.locationtech.jts.geom.Geometry;
import org.locationtech.jts.geom.GeometryFactory;
import org.locationtech.jts.geom.Point;
import org.locationtech.jts.geom.Polygon;
import org.locationtech.jts.geom.PrecisionModel;
import org.locationtech.jts.geom.impl.PackedCoordinateSequenceFactory;

public class KrigingInterpolation {
    public static void main(String[] args) throws Exception {
        // 读取DEM数据
        File demFile = new File("path/to/dem.tif");
        GridCoverage2DReader demReader = new ArcGridReader(demFile);
        GridCoverage2D dem = demReader.read(null);

        // 获取DEM的坐标系
        CoordinateReferenceSystem demCrs = dem.getCoordinateReferenceSystem();

        // 获取DEM的Envelope
        Envelope demEnvelope = dem.getEnvelope();

        // 构造插值点数据
        List<Point> points = new ArrayList<>();
        points.add(createPoint(115.5, 39.8));
        points.add(createPoint(116.0, 39.9));
        points.add(createPoint(116.5, 39.8));
        points.add(createPoint(116.0, 39.7));

        // 创建插值点的Envelope
        ReferencedEnvelope pointsEnvelope = new ReferencedEnvelope(demCrs);
        for (Point point: points) {
            pointsEnvelope.expandToInclude(point.getX(), point.getY());
        }

        // 计算插值点在DEM中的像元坐标
        GridGeometry demGeometry = dem.getGridGeometry();
        GridCoordinates[] coords = new GridCoordinates[points.size()];
        for (int i = 0; i < points.size(); i++) {
            DirectPosition2D point2D = new DirectPosition2D(demCrs, points.get(i).getX(), points.get(i).getY());
            GridCoordinates gridCoord = demGeometry.worldToGrid(point2D);
            coords[i] = gridCoord;
        }

        // 创建插值结果的Envelope
        ReferencedEnvelope resultEnvelope = new ReferencedEnvelope(demCrs);
        resultEnvelope.expandToInclude(demEnvelope);
        resultEnvelope.expandToInclude(pointsEnvelope);

        // 创建插值结果的GridGeometry
        GridGeometry resultGeometry = new GridGeometry(null, resultEnvelope, demGeometry.getGridToCRS());

        // 创建插值器
        Interpolator2D interpolator = new KrigingInterpolator();

        // 设置插值器参数
        ParameterValueGroup params = CommonFactoryFinder.getGridCoverageFactory(null).getDefaultParameters(interpolator);
        params.parameter("radius").setValue(100.0);

        // 进行插值
        GridCoverageFactory coverageFactory = GridCoverageFactoryFinder.getGridCoverageFactory(null);
        GridCoverage2D result = coverageFactory.create("result", new BufferedImage(1, 1, BufferedImage.TYPE_BYTE_GRAY), resultEnvelope);
        interpolator.interpolate(dem, result, coords, params);

        // 输出插值结果
        RenderedOp renderedOp = JAI.create("display", result.getRenderedImage());
        JAI.create("filestore", renderedOp, "path/to/result.tif", "TIFF");
    }

    private static Point createPoint(double x, double y) {
        GeometryFactory factory = new GeometryFactory(new PrecisionModel(), 4326, PackedCoordinateSequenceFactory.DOUBLE_FACTORY);
        return factory.createPoint(new DirectPosition2D(DefaultGeographicCRS.WGS84, x, y));
    }
}

上面的代码中，我们首先读取了一个DEM数据，然后构造了一些插值点数据，并计算了插值点在DEM中的像元坐标。接着，我们创建了一个插值结果的Envelope和GridGeometry，然后使用KrigingInterpolator对DEM进行插值，并输出插值结果。