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ArcEngine 栅格数据 总结

程序开发 2023-09-04 23:32:19

本文大部分内容参考AO帮助文档和ArcMap帮助文档，大家实际使用中遇到的问题也可以在本帖下方留言交流，谢谢！
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基础知识

栅格数据基础知识：传送门
栅格数据相关博文：栅格那点儿事儿

栅格数据是由一系列等间距的格网矩阵组成，用来表达完整的主题、光谱、图像信息。
栅格数据模型分为栅格数据集（Raster dataset）、栅格目录（Raster catalog）、镶嵌数据集（Mosaic dataset）。他们以文件系统、个人地理数据库、文件地理数据库、企业地理数据库为数据源进行存储。

栅格数据集也就是我们经常所得的jpg、tif文件等， ArcGIS 将这些栅格数据抽象为 RasterDataset，栅格数据集就代表了磁盘中的一个文件，它由一个或多个波段组成。在使用栅格数据集的时候，栅格数据会被转换成 IMG 文件存储在数据库中。我们可以对栅格数据集进行一些操作，如改变空间参考，建立影像金字塔等。

栅格目录，正如其名字一样是一个目录，跟书的目录相似，它记录了一个或者多个栅格数据集，每一个栅格数据集都作为一条记录存储在栅格目录中。栅格目录对栅格数据集的管理有两种方式，托管和非托管。托管方式的时候，栅格数据是存储在数据库中， 非托管的时候，栅格目录记录了栅格数据集的路径，也就是栅格数据并没有存储在数据库中。当我们删除一条记录的时候，对我们的栅格数据没有任何影响。

镶嵌数据集可以说是栅格数据集和栅格目录的混合技术，它的存储方式和栅格目录类似，但是在使用的时候和普通的栅格数据集是一样的，镶嵌数据集用于管理和发布海量多分辨率，多传感器影像，对栅格数据提供了动态镶嵌和实时处理的功能。
对文件地理数据库、个人地理数据库和 ArcSDE 地理数据库中的栅格存储加以比较：
这里写图片描述

类图

在线地址：传送门
本地路径：本地路径：如 C:Program Files (x86)ArcGISDeveloperKit10.2DiagramsDataSourcesRasterObjectModel.pdf
##和栅格数据集有关的GP工具
这里写图片描述

栅格数据接口使用示例

这里写图片描述

打开栅格数据工作空间

//Open a file geodatabase workspace as RasterWorkspace.
 static IRasterWorkspaceEx OpenFGDB(string FGDBPath)
 {//FGDBPath string example: c:dataraster.gdb.IWorkspaceFactory2 workspaceFactory = new FileGDBWorkspaceFactoryClass();return (IRasterWorkspaceEx)workspaceFactory.OpenFromFile(FGDBPath, 0);
 }//Open an ArcSDE workspace as RasterWorkspace.
 static IRasterWorkspaceEx OpenSDE(string conString)
 {//conString example: SERVER=ais;INSTANCE=9200;VERSION=sde.DEFAULT;USER=raster;PASSWORD=raster.IWorkspaceFactory2 workspaceFactory = new SdeWorkspaceFactoryClass();return (IRasterWorkspaceEx)workspaceFactory.OpenFromString(conString, 0);
 }//Open an accessed workspace as RasterWorkspace.
 static IRasterWorkspaceEx OpenAccess(string PGDBPath)
 {//FGDBPath string example: c:datarasters.mdb.IWorkspaceFactory2 workspaceFactory = new AccessWorkspaceFactoryClass();return (IRasterWorkspaceEx)workspaceFactory.OpenFromFile(PGDBPath, 0);
 }//Open a file workspace as RasterWorkspace.
 static IRasterWorkspace OpenFileWorkspace(string wsPath)
 {//wsPath example: c:datarasters.IWorkspaceFactory workspaceFact = new RasterWorkspaceFactoryClass();return (IRasterWorkspace)workspaceFact.OpenFromFile(wsPath, 0);
 }

打开栅格数据集

IRasterDataset rasterDataset = rasterWorkspace.OpenRasterDataset(datasetName);
 
IRasterDataset rasterDataset = rasterWorkspaceEx.OpenRasterDataset(datasetName);

创建栅格数据集

  1. Creating a raster dataset（创建以文件存储的栅格数据集，如TIFF）
    1)Create a workspace.创建工作空间
    2)Create a TIFF file with specified width, height, pixel type, cell size, and other necessary dimensions.创建一个TIFF文件，并指定它的宽度,高度,像素类型、像元大小和其他必要的维度。
    3)Use the IPixelBlock and IRasterEdit interfaces to edit the pixel values.使用IPixelBlock 和 IRasterEdit 接口来编辑像元的值。
public static IRasterDataset CreateRasterDataset(string Path, string FileName)
 {try{IRasterWorkspace2 rasterWs = OpenRasterWorkspace(Path);//Define the spatial reference of the raster dataset.ISpatialReference sr = new UnknownCoordinateSystemClass();//Define the origin for the raster dataset, which is the lower left corner of the raster.IPoint origin = new PointClass();origin.PutCoords(15.0, 15.0);//Define the dimensions of the raster dataset.int width = 100; //This is the width of the raster dataset.int height = 100; //This is the height of the raster dataset.double xCell = 30; //This is the cell size in x direction.double yCell = 30; //This is the cell size in y direction.int NumBand = 1; // This is the number of bands the raster dataset contains.//Create a raster dataset in TIFF format.IRasterDataset rasterDataset = rasterWs.CreateRasterDataset(FileName, "TIFF", origin, width, height, xCell, yCell, NumBand, rstPixelType.PT_UCHAR, sr,true);//If you need to set NoData for some of the pixels, you need to set it on band //to get the raster band.IRasterBandCollection rasterBands = (IRasterBandCollection)rasterDataset;IRasterBand rasterBand;IRasterProps rasterProps;rasterBand = rasterBands.Item(0);rasterProps = (IRasterProps)rasterBand;//Set NoData if necessary. For a multiband image, a NoData value needs to be set for each band.rasterProps.NoDataValue = 255;//Create a raster from the dataset.IRaster raster = rasterDataset.CreateFullRaster();//Create a pixel block using the weight and height of the raster dataset. //If the raster dataset is large, a smaller pixel block should be used. //Refer to the topic "How to access pixel data using a raster cursor".IPnt blocksize = new PntClass();blocksize.SetCoords(width, height);IPixelBlock3 pixelblock = raster.CreatePixelBlock(blocksize)as IPixelBlock3;//Populate some pixel values to the pixel block.System.Array pixels;pixels = (System.Array)pixelblock.get_PixelData(0);for (int i = 0; i < width; i++)for (int j = 0; j < height; j++)if (i == j)pixels.SetValue(Convert.ToByte(255), i, j);elsepixels.SetValue(Convert.ToByte((i * j) / 255), i, j);pixelblock.set_PixelData(0, (System.Array)pixels);//Define the location that the upper left corner of the pixel block is to write.IPnt upperLeft = new PntClass();upperLeft.SetCoords(0, 0);//Write the pixel block.IRasterEdit rasterEdit = (IRasterEdit)raster;rasterEdit.Write(upperLeft, (IPixelBlock)pixelblock);//Release rasterEdit explicitly.System.Runtime.InteropServices.Marshal.ReleaseComObject(rasterEdit);return rasterDataset;}catch (Exception ex){System.Diagnostics.Debug.WriteLine(ex.Message);return null;}
 }public static IRasterWorkspace2 OpenRasterWorkspace(string PathName)
 {//This function opens a raster workspace.try{IWorkspaceFactory workspaceFact = new RasterWorkspaceFactoryClass();return workspaceFact.OpenFromFile(PathName, 0)as IRasterWorkspace2;}catch (Exception ex){System.Diagnostics.Debug.WriteLine(ex.Message);return null;}
 }
  1. Creating a raster dataset in a geodatabase（创建以GDB存储的栅格数据集，如GRID）
    1)Create a file geodatabase workspace factory.创建哥FGDB的工作工厂对象。
    2)Create a raster workspace and query IRasterWorkspaceEx.创建一个栅格工作空间对象并且转换到IRasterWorkspaceEx对象上
    3)Define the storage and raster properties using the RasterStorageDef and RasterDef classes. 利用RasterStorageDef 和RasterDef 类定义栅格数据集的存储和栅格属性。
    4)Create the dataset using the CreateRasterDataset method.利用CreateRasterDataset方法创建栅格数据集。
IWorkspaceFactory wsf = new FileGDBWorkspaceFactoryClass();
 IRasterWorkspaceEx ws = (IRasterWorkspaceEx)wsf.OpenFromFile(@"c:tempfgdb.gdb", 0);//Define the raster storage.
 IRasterStorageDef storage = new RasterStorageDefClass();
 storage.Tiled = true;
 storage.TileHeight = 128;
 storage.TileWidth = 128;//Define the spatial reference.
 IRasterDef rasterDef = new RasterDefClass();
 rasterDef.SpatialReference = new UnknownCoordinateSystemClass();//Create data.
 IRasterDataset rasterDs = ws.CreateRasterDataset("newraster", 3,
 rstPixelType.PT_SHORT, storage, "sde.DEFAULT", rasterDef, null);

访问HDF和NIFF数据的子集

一些栅格格式,如分层数据格式(HDF),可以在单个文件中包含多个subdatasets。访问HDF subdatasets使用IRasterDatasetJukebox接口,请参见下面的代码示例:

IWorkspaceFactory wsf = new FileGDBWorkspaceFactoryClass();
 IRasterWorkspaceEx ws = (IRasterWorkspaceEx)wsf.OpenFromFile(@"c:tempfgdb.gdb", 0);//Define the raster storage.
 IRasterStorageDef storage = new RasterStorageDefClass();
 storage.Tiled = true;
 storage.TileHeight = 128;
 storage.TileWidth = 128;//Define the spatial reference.
 IRasterDef rasterDef = new RasterDefClass();
 rasterDef.SpatialReference = new UnknownCoordinateSystemClass();//Create data.
 IRasterDataset rasterDs = ws.CreateRasterDataset("newraster", 3,
 rstPixelType.PT_SHORT, storage, "sde.DEFAULT", rasterDef, null);

读取JPEG EXIF扩展标记信息

public static void JPEG_EXIFtag(IRasterDataset exifDataset)
 {//exifDataset represents a raster dataset opened from a JPEG file that has EXIF tags.IDataset dataset = (IDataset)exifDataset;//Get the EXIF tags and the associated values.IPropertySet propertySet = dataset.PropertySet;    System.Object tag_names;System.Object tag_values;propertySet.GetAllProperties(out tag_names, out tag_values);string[] stringNames = (string[])tag_names;object[] stringValues = (object[])tag_values;for (int i = 0; i < stringNames.Length - 1; i++)    {System.Console.WriteLine(stringNames[i]);System.Console.WriteLine(stringValues[i]);    }
 }

读取像素数据

public static void UsingRasterCursorWithPixelBlock(IRasterDataset2 rasterDs)
 {try{//Create a raster. IRaster2 raster2 = rasterDs.CreateFullRaster()as IRaster2;//Create a raster cursor with a system-optimized pixel block size by passing a null.IRasterCursor rasterCursor = raster2.CreateCursorEx(null);//Use the IRasterEdit interface.IRasterEdit rasterEdit = raster2 as IRasterEdit;//Loop through each band and pixel block.IRasterBandCollection bands = rasterDs as IRasterBandCollection;IPixelBlock3 pixelblock3 = null;long blockwidth = 0;long blockheight = 0;System.Array pixels;IPnt tlc = null;object v;long bandCount = bands.Count;do{pixelblock3 = rasterCursor.PixelBlock as IPixelBlock3;blockwidth = pixelblock3.Width;blockheight = pixelblock3.Height;pixelblock3.Mask(255);for (int k = 0; k < bandCount; k++){//Get the pixel array.pixels = (System.Array)pixelblock3.get_PixelData(k);for (long i = 0; i < blockwidth; i++){for (long j = 0; j < blockheight; j++){//Get the pixel value.v = pixels.GetValue(i, j);//Do something with the value.}}//Set the pixel array to the pixel block.pixelblock3.set_PixelData(k, pixels);}//Write back to the raster.tlc = rasterCursor.TopLeft;rasterEdit.Write(tlc, (IPixelBlock)pixelblock3);}while (rasterCursor.Next() == true);System.Runtime.InteropServices.Marshal.ReleaseComObject(rasterEdit);}catch (Exception ex){System.Diagnostics.Debug.WriteLine(ex.Message);}
 }
public static void ReadWriteRawBlocks(IRasterDataset rasDs)
 {IRasterBandCollection rasBandCol = (IRasterBandCollection)rasDs;IRawBlocks rawBlocks;IRasterInfo rasInfo;IPixelBlock pb;// Iterate through each band of the dataset.for (int m = 0; m <= rasBandCol.Count - 1; m++){// QI to IRawBlocks from IRasterBandCollection.rawBlocks = (IRawBlocks)rasBandCol.Item(m);rasInfo = rawBlocks.RasterInfo;// Create the pixel block.pb = rawBlocks.CreatePixelBlock();// Determine the tiling scheme for the raster dataset.int bStartX = (int)Math.Floor((rasInfo.Extent.Envelope.XMin -rasInfo.Origin.X) / (rasInfo.BlockWidth * rasInfo.CellSize.X));int bEndX = (int)Math.Ceiling((rasInfo.Extent.Envelope.XMax -rasInfo.Origin.X) / (rasInfo.BlockWidth * rasInfo.CellSize.X));int bStartY = (int)Math.Floor((rasInfo.Origin.Y -rasInfo.Extent.Envelope.YMax) / (rasInfo.BlockHeight *rasInfo.CellSize.Y));int bEndY = (int)Math.Ceiling((rasInfo.Origin.Y -rasInfo.Extent.Envelope.YMin) / (rasInfo.BlockHeight *rasInfo.CellSize.Y));// Iterate through the pixel blocks.for (int pbYcursor = startY; pbYcursor < endY; pbYcursor++){for (int pbXcursor = startX; pbXcursor < endX; pbXcursor++){// Get the pixel block.rawBlocks.ReadBlock(pbXcursor, pbYcursor, 0, pb);System.Array safeArray;// Put the pixel block into a SafeArray for manipulation.safeArray = (System.Array)pb.get_SafeArray(0);// Iterate through the pixels in the pixel block.for (int safeArrayHeight = 0; safeArrayHeight < pb.Height;safeArrayHeight++){for (int safeArrayWidth = 0; safeArrayWidth < pb.Width;safeArrayWidth++){// Use System.Array.SetValue to write the new pixel value back into the SafeArray.safeArray.SetValue(Convert.ToByte(128), safeArrayWidth,safeArrayHeight);}}// Set the SafeArray back to the pixel block.pb.set_SafeArray(0, safeArray);// Write the pixel block back to the dataset.rawBlocks.WriteBlock(pbXcursor, pbYcursor, 0, pb);}}}
 }

创建栅格属性表

static void BuildRasterAttributeTable(IRasterDataset rasterDataset, ITable table)
 {//Cast to IRasterDatasetEdit2 to build a raster attribute table.IRasterDatasetEdit2 rasterDatasetEdit = (IRasterDatasetEdit2)rasterDataset;//Build a default raster attribute table with VALUE and COUNT fields.if (table == null){rasterDatasetEdit.BuildAttributeTable();}else{//Assign the given table as the raster attribute table.rasterDatasetEdit.AlterAttributeTable(table);}
 }

读取栅格数据属性（官方文档）

这里写图片描述

主要用到的接口：

  1. IRasterProps
  2. IRasterBandCollection
  3. IRasterDataset
  4. IRasterPyramid3
  5. IRasterBand
    栅格属性列表：
    列数和行数（Columns and Rows)：通过IRasterProps的Width和Height属性获取
    波段数量(Number of Bands)：通过IRasterBandCollection接口获取(可以由IRaster对象跳转接口到此接口）
    像元大小(CellSize(X，Y))：通过IRasterProps的MeanCellSize
    格式(Format):通过IRasterDataset的Format属性获取
    源类型（Source Type）：可以通过GP工具SetRasterProperties来设置。
    像素类型（Pixel Type）：通过IRasterProps接口的PixelType 属性获取
    像素位深（Pixel Depth）：根据像素类型来判断像素位深
    无数据值（NoData Value)：通过IRasterProps 的NoDataValue属性获取
    颜色表/色带（Colormap）：通过IRaster2接口的Colormap属性获取色带
    金字塔（Pyramids）：通过IRasterPyramid3接口来创建、获取、删除金字塔（PS：用IRasterDataset接口跳转到IRasterPyramid3接口）
    压缩（Compression）：通过IRasterDataset的CompressionType属性获取压缩类型
    范围（Extent）：将IRasterDataset接口对象转换成IGeoDataset对象来范围信息
    空间参考（Spatial Reference）：1）将IRasterDataset接口对象转换成IGeoDataset对象来获取空间参考信息 2）通过IRasterProps 的属性SpatialReference获取 3）其它方法
    统计（Statistics）：通过IRasterBand接口的Statistics属性获取波段的统计信息
    波段集合：通过IRasterBandCollection 接口来添加、删除、获取波段。

构建金字塔

构建金字塔有两种方式：1）利用IRasterPyramid3接口来创建金字塔 2）利用GP工具创建金字塔
示例代码：
1）

IRasterPyramid3 pRasterPyramid = rasterDataset as IRasterPyramid3;
 if (pRasterPyramid != null && !pRasterPyramid.Present)
 {//-1代表创建全部级别的金字塔，0代表删除金字塔，其它代表创建对应级别的金字塔pRasterPyramid.BuildPyramid(-1, rstResamplingTypes.RSP_NearestNeighbor);
 }

2）
这里写图片描述

//如何监听GP消息请参考文章《ArcEngine GP笔记（持续补充中......)》
 ESRI.ArcGIS.DataManagementTools.BuildPyramids buildPyramids = new ESRI.ArcGIS.DataManagementTools.BuildPyramids();
 buildPyramids.in_raster_dataset = sRasterFile; //栅格数据源
 buildPyramids.resample_technique = cmbEditResample.Text; //重分类方法
 buildPyramids.compression_type = cmbEditCompressType.Text; //压缩类型
 buildPyramids.compression_quality = Convert.ToInt32(txtCompressQuality.Text); //压缩质量
 IGeoProcessorResult gpResult = m_geoProcesser.Execute(buildPyramids, null);
 if (gpResult.Status == ESRI.ArcGIS.esriSystem.esriJobStatus.esriJobSucceeded)
 {//do something 
 }

个人经验：遇到数据量大的数据创建金字塔比较耗时，建议使用第二种方式GP工具创建金字塔，可以对GP工具进行监听，实时输出动态消息；数据量小的时候可以使用接口，简单快捷。个人经验仅供参考，如有意见，请留言！

栅格数据另存

栅格数据另存有两种方式：①利用ISaveAs和ISaveAs2接口 ②利用GP工具另存
示例代码：
1）ISaveAs2接口另存图片

//去黑边
 IRasterProps pRasterProps=pRaster as IRasterProps;
 pRasterProps.NoDataValue=255;
 //另存输出
 ISaveAs2 pSaveAs = pRaster as ISaveAs2;
 if (!pSaveAs.CanSaveAs(sFormat))
 {XtraMessageBox.Show("不支持指定像素类型或文件格式的输出", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);return ;
 }
 IWorkspaceFactory worksapceFactory = new RasterWorkspaceFactoryClass();
 workspace = worksapceFactory.OpenFromFile(System.IO.Path.GetDirectoryName(m_sOutputPath), 0);
 IDataset dataset = pSaveAs.SaveAs(System.IO.Path.GetFileName(m_sOutputPath), workspace, sFormat);

个人经验： ISaveAs 保存Grid格式数据技巧
2）可以利用CopyRaster工具拷贝一份栅格数据实现栅格数据的另存。

栅格数据裁切

栅格数据裁切有两种方式：①利用接口进行裁切 ②利用GP工具进行裁切
1）利用接口进行裁切
①基于IEnvelope对象裁切，主要用到的接口：IRasterGeometryProc

IRasterGeometryProc pRasterGeometryProc = new RasterGeometryProcClass();
 pRasterGeometryProc.Clip(pClipEnvelope,pInputRaster)

②利用 IExtractionOp2接口进行裁切，然后用ISaveAs2接口保存裁切后的结果。代码链接：传送门（这种方法不支持含孔洞的面作为裁切范围）
③调用IClipFilter裁切，参考链接
④调用IRasterFunction裁切，参考链接

// Create the Function Arguments object.
 IClipFunctionArguments rasterFunctionArguments = (IClipFunctionArguments)newClipFunctionArguments();
 // The input data can be of type IRasterDataset, IRasterBand, or IRaster.
 rasterFunctionArguments.Raster = inputData;
 // Set the parameters for the function:
 // Set the clipping type (clip outside leaves the area inside the envelope untouched)
 rasterFunctionArguments.ClippingType =esriRasterClippingType.esriRasterClippingOutside;
 // Set the extents to clip to by providing a raster envelope object.
 rasterFunctionArguments.ClippingGeometry = rasterEnvelope;// Create the Raster Function object.
 IRasterFunction rasterFunction = new ClipFunction();
 // Create the Function Raster Dataset object.
 IFunctionRasterDataset functionRasterDataset = new FunctionRasterDataset();
 // Create a name object for the Function Raster Dataset.
 IFunctionRasterDatasetName functionRasterDatasetName = (IFunctionRasterDatasetName)new FunctionRasterDatasetName();
 // Specify the output file name for the new dataset (including the .afr extension at the end).
 functionRasterDatasetName.FullName = @"c:tempClip.afr";
 functionRasterDataset.FullName = (IName)functionRasterDatasetName;
 // Initialize the new Function Raster Dataset with the Raster Function and its arguments.
 functionRasterDataset.Init(rasterFunction, rasterFunctionArguments);

2）调用Clip工具进行裁切，代码略（这块我做过基于范围、文件、ROI绘制图形的裁切，不会的可以留言，我可以把示例代码发过去）。
这块有几个注意事项：
① 注意输入数据和裁切范围要有坐标系
② 注意被裁切的数据和裁切范围是否可以叠加上
③ 注意将裁切范围转换到输入数据的坐标系上去
④ 如果基于栅格文件裁切，clipping_geometry设置为 “NONE”；如果基于矢量文件裁切，clipping_geometry设置为 “ClippingGeometry”；
⑤ 如果基于四角坐标裁切，注意rectangle参数格式;如果in_template_dataset不为空字符串或空对象，设置rectangle参数为“#”即可。

in_rectangle = string.Format("{0} {1} {2} {3}", pEnvelope.XMin, pEnvelope.YMin, pEnvelope.XMax, pEnvelope.YMax);

栅格数据可视化

1.栅格数据渲染包括一下几种：

  1. IRasterLayer
  2. IRasterRenderer

这里写图片描述
示例代码暂时略，有问题的同学可以留言。这块想着以后有时间的话以新帖子总结，顺便将色带总结了。

2.栅格图层的显示效果
栅格图层的显示效果受亮度、对比度、透明度等因素的影响。
用到的接口：
1)ILayerEffects
2)IRasterDisplayProps

栅格数据分析

分享几个我项目中用到的栅格分析功能的例子：
1)坡度分析

private IRaster ProduceSlopeData(DirectoryInfo demFile, string outputFolder,string strOutputMeasurement, double zFactor, IGeoDataset inputGeoDataset, IWorkspace pWorkspace)
 {IRaster solpeRaster = null;ISurfaceOp pSurface = new RasterSurfaceOpClass();esriGeoAnalysisSlopeEnum enumSlope = (strOutputMeasurement == "DEGREE") ? esriGeoAnalysisSlopeEnum.esriGeoAnalysisSlopeDegrees :esriGeoAnalysisSlopeEnum.esriGeoAnalysisSlopePercentrise;IGeoDataset outSlopeDataset = pSurface.Slope(inputGeoDataset, enumSlope, zFactor);//输出坡度数据ISaveAs pSlopeSaveAs = outSlopeDataset as ISaveAs;string outputSlopeName = demFile.Parent.Name.ToUpper() +"SLP";//string outputSlopeName = demFile.Parent.Name + "SLP.tif";if (System.IO.File.Exists(System.IO.Path.Combine(outputFolder, outputSlopeName))){IRasterDataset oldRasterDataset = (pWorkspace as IRasterWorkspace).OpenRasterDataset(outputSlopeName);(oldRasterDataset as IDataset).Delete();}IDataset solpeDataset = pSlopeSaveAs.SaveAs(outputSlopeName, pWorkspace, "GRID");//IDataset solpeDataset = pSlopeSaveAs.SaveAs(outputSlopeName, pWorkspace, "TIFF");IRasterDataset solpeRasterDataset = solpeDataset as IRasterDataset;if (solpeRasterDataset != null){solpeRaster = solpeRasterDataset.CreateDefaultRaster();}System.Runtime.InteropServices.Marshal.ReleaseComObject(outSlopeDataset);System.Runtime.InteropServices.Marshal.ReleaseComObject(solpeRasterDataset);return solpeRaster;
 }

2)坡向分析

private void ProduceAspectData(DirectoryInfo demFile, string outputFolder, IGeoDataset inputGeoDataset, IWorkspace pWorkspace)
 {ISurfaceOp pSurface = new RasterSurfaceOpClass();IGeoDataset outAspectDataset = pSurface.Aspect(inputGeoDataset);ISaveAs pAspectSaveAs = outAspectDataset as ISaveAs;string outputAspectName = demFile.Parent.Name.ToUpper() + "SPD";//string outputAspectName = demFile.Parent.Name + "SPD.tif";string outputAspectFilePath = System.IO.Path.Combine(outputFolder, outputAspectName);if (System.IO.File.Exists(outputAspectFilePath)){IRasterDataset oldRasterDataset = (pWorkspace as IRasterWorkspace).OpenRasterDataset(outputAspectName);(oldRasterDataset as IDataset).Delete();}IDataset aspectDataset = pAspectSaveAs.SaveAs(outputAspectName, pWorkspace, "GRID");//IDataset aspectDataset = pAspectSaveAs.SaveAs(outputAspectName, pWorkspace, "TIFF");System.Runtime.InteropServices.Marshal.ReleaseComObject(outAspectDataset);System.Runtime.InteropServices.Marshal.ReleaseComObject(aspectDataset);
 }

3)重分类

private IRasterDataset ProduceSlopeZone(DirectoryInfo demFile, string outputFolder,IWorkspace pWorkspace, IRaster pInRaster)
 {if (pInRaster == null){m_richTxtBoxLog.SelectionColor = System.Drawing.Color.Red;m_richTxtBoxLog.AppendText("生成高程带数据失败！rn");return null;}IReclassOp pReclassOp = new RasterReclassOpClass();IGeoDataset pGeodataset = pInRaster as IGeoDataset;INumberRemap pNumRemap = new NumberRemapClass();IRasterStatistics pRasterStatistic = GetRasterStatistics(pInRaster);pNumRemap.MapRange(0, 2, 0);pNumRemap.MapRange(2, 3, 2);pNumRemap.MapRange(3, 5, 3);pNumRemap.MapRange(5, 6, 5);pNumRemap.MapRange(6, 8, 6);pNumRemap.MapRange(8, 10, 8);pNumRemap.MapRange(10, 15, 10);pNumRemap.MapRange(15, 25, 15);pNumRemap.MapRange(25, 35, 25);pNumRemap.MapRange(35, 45, 35);if (pRasterStatistic.Maximum > 45){pNumRemap.MapRange(45, 90, 45);}IRemap pRemap = pNumRemap as IRemap;IRaster2 pOutRaster = pReclassOp.ReclassByRemap(pGeodataset, pRemap, false) as IRaster2;//保存ISaveAs pAspectSaveAs = pOutRaster as ISaveAs;string outputAspectName = demFile.Parent.Name.ToUpper() + "SPZA.tif";if (System.IO.File.Exists(System.IO.Path.Combine(outputFolder, outputAspectName))){IRasterDataset oldRasterDataset = (pWorkspace as IRasterWorkspace).OpenRasterDataset(outputAspectName);(oldRasterDataset as IDataset).Delete();}IDataset aspectDataset = pAspectSaveAs.SaveAs(outputAspectName, pWorkspace, "TIFF");System.Runtime.InteropServices.Marshal.ReleaseComObject(pInRaster);return (aspectDataset as IRasterDataset);        
 }/// 
 /// 获取栅格统计
 /// 
 /// 
 /// 
 private IRasterStatistics GetRasterStatistics(IRaster pRaster)
 {if (null == pRaster)return null;IRasterBandCollection pRBandCol = pRaster as IRasterBandCollection;IRasterBand pRBand = pRBandCol.Item(0);if (pRBand.Statistics == null){pRBand.ComputeStatsAndHist();}return pRBand.Statistics;
 }

和栅格数据相关的GP工具箱

和栅格数据有关的工具箱：3D Analyst Tools 、Data Management Tools、Spatial Analyst Tools 等工具箱。

具体内容不在此赘述，有问题的可以留言。

如何去除栅格影像的黑边

参考博客：http://zhihu.esrichina.com.cn/?/question/6725

对于三波段进行RDB渲染的影像可以使用下面代码：

IRasterRenderer RR = RL.Renderer; 
 IRasterRGBRenderer rasterRGBRenderer = null; 
 if (RR is IRasterRGBRenderer) 
 rasterRGBRenderer = RR as IRasterRGBRenderer; 
 RR.Update(); 
 rasterRGBRenderer.RedBandIndex = 0; 
 rasterRGBRenderer.GreenBandIndex = 1; 
 rasterRGBRenderer.BlueBandIndex = 2; 
 IRgbColor rgb = new RgbColorClass(); 
 rgb.NullColor = true; 
 IRasterStretch2 RS = rasterRGBRenderer as IRasterStretch2; // IRasterStretch无法设置数组，需用2 
 double background = 
 { 
 0, 0, 0 
 }; 
 RS.Background = true; 
 RS.BackgroundValue = background as object; 
 RS.BackgroundColor = rgb as IColor; 
 axMapControl1.Refresh();

对于单波段

IRasterRenderer RR = RL.Renderer;
 IRasterStretchColorRampRenderer RSC = null;
 if (RR is IRasterStretchColorRampRenderer)
 RSC = RR as IRasterStretchColorRampRenderer;
 RR.Update();
 RSC.BandIndex = 0;
 IRgbColor rgb = new RgbColorClass(); 
 rgb.NullColor = true; 
 IRasterStretch RS = RSC as IRasterStretch;
 RS.Background = true;
 RS.set_BackgroundValues(0);
 RS.BackgroundColor = rgb as IColor;
 axMapControl1.Refresh();

栅格函数的使用（待补充）

问题记录

  1. ArcGIS栅格裁剪-----裁剪前后的栅格颜色如何保持一致

本文书写参考内容:
1)官方帮助文档
2)个人项目经验
3)参考博客：arcengine栅格数据使用总结
4)相关文档资料：CSDN下载-》ArcEngine 栅格数据总结.ppt


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