ArcEngine栅格影像开发.docVIP

1栅格数据处理常用到的接口： IRaster IRatserLayer IRasterDataset IInterpolationOp IGeoDataset IPixelBlock2 IPnt IRawPixels(read) IRaster(read) 2. 加载栅格数据1) 直接用IRasterLayer接口打开一个栅格文件并加载到地图控件 IRasterLayer rasterLayer = new RasterLayerClass(); rasterLayer.CreateFromFilePath(fileName); // fileName指存本地的栅格文件路径 axMapControl1.AddLayer(rasterLayer, 0); 用IRasterDataset接口打开一个栅格数据集 IWorkspaceFactory workspaceFactory = new RasterWorkspaceFactory(); IWorkspace workspace; workspace = workspaceFactory.OpenFromFile(inPath, 0); //inPath栅格数据存储路径 if (workspace == null) { Console.WriteLine(Could not open the workspace.); return; } IRasterWorkspace rastWork = (IRasterWorkspace)workspace; IRasterDataset rastDataset; rastDataset= rastWork.OpenRasterDataset(inName);//inName栅格文件名 读取栅格数据的属性和遍历栅格数据IRasterProps rasterProps = (IRasterProps)clipRaster; int dHeight = rasterProps.Height;//当前栅格数据集的行数 int dWidth = rasterProps.Width; //当前栅格数据集的列数 double dX = rasterProps.MeanCellSize().X; //栅格的宽度 double dY = rasterProps.MeanCellSize().Y; //栅格的高度 IEnvelope extent=rasterProps.Extent; //当前栅格数据集的范围 rstPixelType pixelType=rasterProps.PixelType; //当前栅格像素类型 IPnt pntSize = new PntClass(); pntSize.SetCoords(dX, dY); IPixelBlock pixelBlock = clipRaster.CreatePixelBlock(pntSize); IPnt pnt = new PntClass(); for (int i = 0; i dHeight; i++) for (int j = 0; j dWidth; j++) { pnt.SetCoords(i, j); clipRaster.Read(pnt, pixelBlock); if (pixelBlock != null) { object obj = pixelBlock.GetVal(0, 0, 0); MessageBox.Show( Convert.ToUInt32(obj).ToString()); } 4. 提取指定的范围的栅格数据提取指定范围内的栅格数据通常用两种方法IRasterLayerExport(esriCarto), IExtractionOp, IExtractionOp2 (esriSpatialAnalyst)，IRasterLayerExport接口提供的栅格数据提取功能有限，只能以矩形范围作为提取范围，而IExtractionOp接口提供了多边形，圆，属性，矩形等几种形式作为提取栅格数据.1).IRasterLayerExport接口 IRasterLayerExport rLayerExport = new RasterLayerExportClass(); rLayerExport.RasterLayer = rasterLayer;// rasterLayer指当前加载的栅格图层 rLayerExport.Extent = clipExtent;//clipExtent指提取栅格数据的范围 if (proSpatialRef != null) rLayerExport.SpatialReference = proSpatialRef;