ArcGIS栅格处理总结.docx

ArcGIS栅格处理总结RealStyle-赵晓鲁2012年9月28日处理栅格数据用到的新的接口有:iconditionalop,Ipnt，IRasterDescriptor, IextractionOp，IrasterLayerExport，IRasterAnalysisEnvironment，ILogicalOp，IReclassOp，IMathOp，INumberRemap，IRemap，ISurfaceop，Irawpixels（很有用）坐标值位置：地图坐标最小X、Y值在左下角，IEnvelope最小值是左下角，最大值是右上角，栅格数据最小行列值是在左上角，最大行列值是在右下角。IRasterAnalysisEnvironment:一般和IextractionOp一起用，用来设置提取出来的栅格数据的一些属性信息。遍历栅格数据所有数据，将像素值存储在二维数组中IWorkspaceFactory pWksfact = new RasterWorkspaceFactoryClass();IRasterWorkspace pRwks = pWksfact.OpenFromFile(F:栅格数据处理集Tempdata, 0) as IRasterWorkspace ;IRaster pRaster = pRwks.OpenRasterDataset(003647.tif).CreateDefaultRaster();IRasterProps pRprops = pRaster as IRasterProps ;IRasterBandCollection pRbcoll = pRaster as IRasterBandCollection ;int pRbcount = pRbcoll.Count ; IPixelBlock3 pPblock3 = null; GC.Collect();/释放内存，强制回收垃圾内存byte, pByte = new bytepRprops.Width, pRprops.Height * pRbcount;/内存占有量为byte类型所占的字节数*pRprops.Width*pRprops.Height * pRbcountSystem.Array pArray = null;/定义一个数组,用来存储pPblock3.get_PixelData(pTindex)获得的像素块的值for (int pTindex = 0; pTindex pRbcount; pTindex+)/遍历每个波段IRasterCursor pRcursor = pRaster.CreateCursor();/128行，全部列是一个pRcursor.Next()，dopPblock3 = pRcursor.PixelBlock as IPixelBlock3;/将每个128行的值放在pPblock3中pArray = pPblock3.get_PixelData(pTindex) as System.Array;/将相应波段的数值存储在数组中for (int pW = 0; pW pArray.GetLength(0); pW+)/列数for (int pH = 0; pH pArray.GetLength(1); pH+)/行数pBytepW, pH * (pTindex + 1) = Convert.ToByte (pArray.GetValue(pW, pH);/给二维数组赋值 while (pRcursor.Next();/获得下一个128行栅格数据ESRI.ArcGIS.ADF.ComReleaser.ReleaseCOMObject(pRcursor );/对对象进行内存释放/遍历每个波段for (int pT = 0; pT pByte.GetLength(0); pT+)/遍历二维数组for (int pTT = 0; pTT pByte.GetLength(1); pTT+)int pp = Convert.ToInt32(pByte.GetValue(pT, pTT);/遍历二维数组1、 如果想将Tif转换为bmp，仅仅需要用到的AO的接口是Isaveas。IWorkspaceFactory pWksfact=newRasterWorkspaceFactoryClass();IRasterWorkspace pRwks = pWksfact.OpenFromFile(F:Temp,0 ) as IRasterWorkspace ;IRasterDataset pRdataset = pRwks.OpenRasterDataset(cbers.tif);IRaster2 pRaster = pRdataset.CreateDefaultRaster() as IRaster2 ;IRasterWorkspace2pRwks2=pWksfact.OpenFromFile(F:Temp,0)asIRasterWorkspace2;ISaveAs pSaveas = pRaster as ISaveAs ;pSaveas.SaveAs(pCreat.BMP, pRwks2 as IWorkspace, BMP);2、 修改栅格数据灰度值：没有用到isaveas用到的接口是：IRasterCursor，IPixelBlock3，System.Array pArray，IRasterEdit，IPntIWorkspaceFactory pWksfact = new RasterWorkspaceFactoryClass();IRasterWorkspace2 pRwks = pWksfact.OpenFromFile(F:Temp, 0) as IRasterWorkspace2 ;IRaster2 pRaster = pRwks.OpenRasterDataset(cbers.tif).CreateDefaultRaster() as IRaster2 ;IRasterProps pRprops = pRaster as IRasterProps; IPoint pPoint = new PointClass () ; pPoint.PutCoords (0,0 ) ; IPnt pPnt = new DblPntClass(); pPnt.SetCoords(pRprops.Width,pRprops.Height );/确定范围IRasterCursor pRcursor = pRaster.CreateCursorEx( pPnt );/确定一个栅格指针的范围，ex：extent，所有要用ppnt，IPixelBlock3 pPblock = pRcursor.PixelBlock as IPixelBlock3 ;System.Array pArray = pPblock.get_PixelData(0) as System.Array;for (int pWidth = 0 ;pWidth pRprops.Width ;pWidth + ) for (int pHeight = 0; pHeight = 1)pHH = 128;elsepHH = pRprops.Height % 128;for (int pH = 0; pH pHH ; pH+)for (int pW = 0; pW pRprops.Width; pW+)if (Convert.ToByte ( pArray.GetValue(pW, pH) = 1)pChangearr.SetValue(pArray.GetValue(pW, pH), pW, pH + 128 * (pT - 1);/赋值定义的数组 while (pRcursor.Next () ) ;/每128行遍历一次IRaster2 pR2 =pRaster as IRaster2 ;IPnt pPnt = new DblPntClass () ;pPnt.SetCoords (pRprops.Width ,pRprops.Height ) ;IRasterCursor pR2cursor = pR2.CreateCursorEx (pPnt ) ; IPixelBlock3 pSpb = pR2cursor.PixelBlock as IPixelBlock3; IPnt pSpnt = new DblPntClass();pSpnt.SetCoords(0, 0); pSpb.set_PixelData(0, pChangearr);/将数组赋值给pSpbIRasterEdit pRedit = pcR as IRasterEdit;pRedit.Write(pSpnt, pSpb as IPixelBlock);/编辑栅格数据集，写完后，栅格数据就会是现在的值模板提取： /找到模板，并将模板放在数组里IWorkspaceFactory pRwksfact = new RasterWorkspaceFactoryClass();IRasterWorkspace pRwks = pRwksfact.OpenFromFile(F:栅格数据处理集Tempdata, 0) as IRasterWorkspace ;IRaster pModelraster = pRwks.OpenRasterDataset(extract_17001).CreateDefaultRaster();IRaster2 pModelraster2 = pModelraster as IRaster2;IRasterProps pModelRprops = pModelraster as IRasterProps;/pModelRprops.NoDataValue = 0;IPnt pModelpnt = new DblPntClass();pModelpnt.SetCoords(pModelRprops.Width,pModelRprops.Height );IRasterCursor pModelrcursor = pModelraster2.CreateCursorEx(pModelpnt);IPixelBlock3 pModelppb3 = pModelrcursor.PixelBlock as IPixelBlock3;System.Array pModelarray = pModelppb3.get_PixelData(0) as System.Array;/找到模板，并将模板放在数组里/找到源文件，将源文件存放到数组里IRaster pOriraster = pRwks.OpenRasterDataset(17002L1).CreateDefaultRaster();IRaster2 pOriraster2 = pOriraster as IRaster2;IRasterProps pOrirprops = pOriraster2 as IRasterProps;/pOrirprops.NoDataValue = 0;IPnt pOripnt = new DblPntClass();pOripnt.SetCoords(pOrirprops.Width, pOrirprops.Height);IRasterCursor pOrircursor = pOriraster2.CreateCursorEx(pOripnt);IPixelBlock3 pOripb3 = pOrircursor.PixelBlock as IPixelBlock3;System.Array pOriarray = pOripb3.get_PixelData(0) as System.Array;/找到源文件，将源文件存放到数组里/创建一个二值的栅格数据if (Directory.Exists(F:栅格数据处理集TempdataPCreate)IDataset pTds = pRwks.OpenRasterDataset(PCreate) as IDataset;pTds.Delete();IGeoDataset pTgeodataset = pOriraster as IGeoDataset;IEnvelope pTenv = pTgeodataset.Extent;IPoint pCpoint = new PointClass();pCpoint.PutCoords(pTenv.XMin, pTenv.YMin);IRasterWorkspace2 pRwks2 = pRwks as IRasterWorkspace2 ;IRasterDataset pCrdataset = pRwks2.CreateRasterDataset(PCreate,GRID,pCpoint,pOrirprops.Width,pOrirprops.Height,pOrirprops.MeanCellSize().X ,pOrirprops.MeanCellSize().Y ,1,rstPixelType.PT_U1 ,pOrirprops.SpatialReference,true );/创建一个二值的栅格数据/创建一个二维数组System.Array pCarray = new byte pOrirprops.Width ,pOrirprops.Height;/计算模板中所有值平方的相加和double pModelsun = 0;int pTemp = 0;for (int pH = 0; pH pModelRprops.Height; pH+)for (int pW = 0; pW =0 )pTemp = Convert.ToInt16 ( pModelarray.GetValue(pW, pH);pModelsun = pModelsun + (Math.Pow(pTemp, 2);/遍历原始栅格数据的行列double pMOmulti = 0;double pOrisun = 0;int pTMod = 0;int pTori = 0;double pScale = 0; for (int pH = 0; pH pOrirprops.Height - pModelRprops.Height; pH+)/遍历每行tryfor (int pW = 0; pW = 0)pMOmulti = 0;pOrisun = 0;pTMod = 0;pTori = 0; for (int pMh = 0; pMh pModelRprops.Height; pMh+)/遍历模型行for (int pMw = 0; pMw = 0)pTori = Convert.ToSByte(pOriarray.GetValue(pW + pMw, pH + pMh);pTMod = Convert.ToSByte(pModelarray.GetValue(pMw, pMh); pMOmulti = pMOmulti + pTori * pTMod; pOrisun = pOrisun + Math.Pow(pTori, 2);if (pOrisun 0)pScale = pMOmulti / (Math.Sqrt(pModelsun) * Math.Sqrt(pOrisun);if (pScale 0.9)for (int pMh = 0; pMh pModelRprops.Height; pMh+)/遍历模型行for (int pMw = 0; pMw pModelRprops.Width; pMw+)/遍历模型列pCarray.SetValue(Convert.ToByte (pOriarray.GetValue(pW + pMw, pH + pMh), pW + pMw, pH + pMh);catchcontinue ;IRaster pCraster = pRwks.OpenRasterDataset(PCreate).CreateDefaultRaster();IRaster2 pCr2 = pCraster as IRaster2;IRasterProps pCrprops = pCr2 as IRasterProps;IPnt pCpnt = new PntClass();pCpnt.SetCoords(pCrprops.Width, pCrprops.Height);IRasterCursor pCrcur = pCr2.CreateCursorEx(pCpnt);IPixelBlock3 pCpb = pCrcur.PixelBlock as IPixelBlock3 ;pCpb.set_PixelData(0, pCarray);IRasterEdit pRedit = pCraster as IRasterEdit;IPnt pTlpnt = new PntClass();pTlpnt.SetCoords(0, 0);pRedit.Write(pTlpnt, pCpb as IPixelBlock);pixel value是栅格象元的值，stretched value是该象元显示时用的值。因显示器显示时必须把象元值转换到0255显示，所以就有了stretched value。IRasterProps pRprops = pRaster as IRasterProps;pRprops.NoDataValue = 2;为空白区域赋值，将nodata空白区域赋上pixel值，而不是stretched value。单元值可正可负，可以是整型也可以是浮点型。在单元中，还可以使用 NoData 值来表示数据缺失。显示具有 NoData 值的栅格时，所有渲染器可将 NoData 值设置为某个颜色或无颜色；然而，“拉伸”渲染器可识别特定背景值并显示颜色或无颜色。Nodata相关操作在栅格数据进行叠加运算时，如果有些区域的值为nodata那么这些区域的值和其他任何栅格数据相加的在值都是nodata，所以有时候需要将nodata区域设置为0。可以通过SetNull将有些值设置为nodata，也可以通过IsNull来确定哪些区域是nodata区域。ILogicalOp pLogicalop = new RasterMathOpsClass();/获得ILogicalop接口，用于数学运算IRaster pOutr = pLogicalop.IsNull(pRaster as IGeoDataset ) as IRaster ;/如果数据缺失，那么输出为1，否则输出为0.Con 可以将栅格数据中的某些值（通过条件查询）设置为想要的区域，将某些不想要的区域设置为其它值（可以是自己设置的也可以是输入的固定值）IConditionalOp: 方法Con，IConditionalOp. Con(IGeoDataset conditionalRaster, IGeoDataset trueRaster, ref object falseRaster) 方法：不管conditionalRaster是仅有0和1的值，还是有多个值的栅格数据，只要是值大于0的栅格像素值，赋的值都是trueRaster，凡是值等于0的栅格像素值那么赋值为falseRaster，falseRaster可以为一个常数，也可以为一个栅格数据集（Raster）对应的像素值。IConditionalOp. Con代码IWorkspaceFactory pWksfact = new RasterWorkspaceFactoryClass();IRasterWorkspace pRwks = pWksfact.OpenFromFile(F:栅格数据处理集Tempdata, 0) as IRasterWorkspace ;IRaster pRaster = pRwks.OpenRasterDataset(cbers.tif).CreateDefaultRaster();IRaster pSraster = new RasterClass();/object pint = 100;/object为常数object pRa = pRaster;/object为栅格数据集IConditionalOp pConditionalop = new RasterConditionalOpClass();/pSraster = pConditionalop.Con(pRaster as IGeoDataset, pRaster as IGeoDataset , ref pint) as IRaster ;/object为常数pSraster = pConditionalop.Con(pRaster as IGeoDataset, pRaster as IGeoDataset, ref pRa) as IRaster;/object为栅格数据集ISaveAs pSa = pSraster as ISaveAs;pSa.SaveAs(nihao2.tif, pRwks as IWorkspace, TIFF);使用“设为空函数”将值设置为 NoData：在spatial analyst下的conditional下的set null。要将值大于 5 的像元设置为 NoData，并且保留其他像元的原始值，请在工具对话框中使用以下参数：输入条件栅格：InRas1表达式：Value 5(条件)求值结果为 False 的输入栅格或常数值：InRas1（即不符合条件的像素值设置为输入栅格对应的值）输出栅格：setnull_1IConditionalOp:只是针对栅格数据只有两个值的0和1的栅格，如果只有0和1，那么将值为1的设置为空，值为0的仍然为0，或者是其它栅格（False Raster）数据相应位置的值。或者栅格数据有多个值，0和大于0两类，当栅格数据有多个值时，值大于0的设置为空，值等于0的仍然是0或者是其它栅格数据（False Raster）相应位置的值。和conditional下的set null理解差不多，但是有区别，不能设置”sql语句”。 将大于0的值变为nodata，将等于0的值变为falseraster的栅格像素值。用到的接口是 IConditionalOp方法是： SetNull相应 的代码：IWorkspaceFactory pWksfact = new RasterWorkspaceFactoryClass();IRasterWorkspace pRwks = pWksfact.OpenFromFile(F:Temp,0) as IRasterWorkspace ;IRaster2 pRaster = pRwks.OpenRasterDataset(cbers.tif).CreateDefaultRaster() as IRaster2; IRaster2 pR2 = pRwks.OpenRasterDataset(hh).CreateDefaultRaster() as IRaster2; IConditionalOp pCondi = new RasterConditionalOpClass();IGeoDataset pDataset = pRaster as IGeoDataset;IGeoDataset pFdataset = pR2 as IGeoDataset;IGeoDataset pOutdataset = pCondi.SetNull(pDataset ,pFdataset );ISaveAs pSa = pOutdataset as ISaveAs;pSa.SaveAs( nihao.tif,pRwks as IWorkspace ,TIFF ); 通过一个面的范围来提取栅格数据：IWorkspaceFactory pWksfact = new RasterWorkspaceFactoryClass();IRasterWorkspace pRwks = pWksfact.OpenFromFile(F:Temp,0) as IRasterWorkspace ;IRaster2 pRaster = pRwks.OpenRasterDataset(cbers.tif).CreateDefaultRaster() as IRaster2;IRasterProps pRprops = pRaster as IRasterProps ;IExtractionOp pExtra = new RasterExtractionOpClass();IWorkspaceFactory pSwksfact = new ShapefileWorkspaceFactoryClass();IFeatureWorkspace pFwks = pSwksfact.OpenFromFile(F:Temp, 0) as IFeatureWorkspace ;IFeatureClass pFclass = pFwks.OpenFeatureClass(mian);IFeatureCursor pFcur = pFclass.Search(null,false );IFeature pFeature = pFcur.NextFeature();IPolygon pPolygon = pFeature.Shape as IPolygon ; IWorkspace pOutwks = pWksfact.OpenFromFile(F:Temp, 0);IGeoDataset pGeodataset = pRaster as IGeoDataset; IGeoDataset pOutgd = pExtra.Polygon(pGeodataset ,pPolygon,true ) as IGeoDataset ;/true指的是面内的栅格提取出来，false指的是面外的栅格数据提取出来，IRaster pOutr = pOutgd as IRaster;/将Geodataset转换为iraster，而不是转换为irasterdataset，用isaveas来保存存储在内存中的栅格数据。ISaveAs pSa = (ISaveAs ) pOutr ;pSa.SaveAs(jj.tif, pOutwks, TIFF);/poutwks一定要是栅格工作空间工厂打开的工作空间，不能是其它工作空间工厂打开的工作空间。通过属性提取栅格数据IWorkspaceFactory pWksfact = new RasterWorkspaceFactoryClass();IRasterWorkspace pRwks = pWksfact.OpenFromFile(F:Temp,0) as IRasterWorkspace ;IRaster2 pRaster = pRwks.OpenRasterDataset(cbers.tif).CreateDefaultRaster() as IRaster2;IRasterProps pRprops = pRaster as IRasterProps ;IExtractionOp pExtra = new RasterExtractionOpClass();IQueryFilter pQueryfilter = new QueryFilterClass () ;/属性查询，查询到属性值是多少的像素。 pQueryfilter.WhereClause = Value=109;/设置像素查询的条件。IRasterDescriptor pRdescriptor = new RasterDescriptorClass();/栅格描述接口。pRdescriptor.Create(pRaster as IRaster, pQueryfilter, Value);IWorkspaceFactory pRwks2 = new RasterWorkspaceFactoryClass();IWorkspace pWks2 = pRwks2.OpenFromFile(F:Temp, 0);IRaster pOut2 = pExtra.Attribute(pRdescriptor) as IRaster;/将获得的栅格数据给irasterISaveAs poUTas = pOut2 as ISaveAs ;poUTas.SaveAs(temPp.tif,pWks2 ,TIFF);通过范围（Rectangle）来提取栅格数据 IWorkspaceFactory pWksfact = new RasterWorkspaceFactoryClass();IRasterWorkspace pRwks = pWksfact.OpenFromFile(F:Temp,0) as IRasterWorkspace ;IRaster2 pRaster = pRwks.OpenRasterDataset(cbers.tif).CreateDefaultRaster() as IRaster2;IRasterProps pRprops = pRaster as IRasterProps ; IWorkspaceFactory pSwksfact = new ShapefileWorkspaceFactoryClass(); IFeatureWorkspace pFwks = pSwksfact.OpenFromFile(F:Temp, 0) as IFeatureWorkspace ;IFeatureClass pFclass = pFwks.OpenFeatureClass(mian);IFeatureCursor pFcur = pFclass.Search(null, false);IFeature pFeature = pFcur.NextFeature();IEnvelope pEnv = pFeature.Extent; /获取范围IExtractionOp pEx = new RasterExtractionOpClass();IRaster pOraster = pEx.Rectangle(pRaster as IGeoDataset, pEnv, true) as IRaster ;ISaveAs pSa = pOraster as ISaveAs;/保存pSa.SaveAs(pOraster.tif,pRwks as IWorkspace ,TIFF);通过矩形（Rectangle）来导出地图坐标最小X、Y值在左下角，IEnvelope最小值是左下角，最大值是右上角，栅格数据最小行列值是在左上角，最大行列值是在右下角。double pXmin, pXmax, pYmin, pYmax;IEnvelope pEnv = new EnvelopeClass();pR2.PixelToMap(pW, pH + pRprops.Height, out pXmin, out pYmin);/获得xy值的最小值pR2.PixelToMap(pW + pRprops.Width ,pH,out pXmax ,out pYmax );/获得xy值得最大值pEnv.PutCoords(pXmin, pYmin, pXmax, pYmax);/设置IEnvelope的范围IExtractionOp pExtractop = new RasterExtractionOpClass();IRaster pSraster = pExtractop.Rectangle(pR as IGeoDataset, pEnv, true) as IRaster;ISaveAs pSa = pSraster as ISaveAs;pSa.SaveAs(Ptiqu + Pc , pRwks as IWorkspace, GRID);通过栅格数据提取栅格数据IWorkspaceFactory pWksfact = new RasterWorkspaceFactoryClass();IRasterWorkspace pRwks = pWksfact.OpenFromFile(F:Temp,0) as IRasterWorkspace ;IRaster2 pRaster = pRwks.OpenRasterDataset(cbers.tif).CreateDefaultRaster() as IRaster2;/获得待提取的栅格数据IRasterProps pRprops = pRaster as IRasterProps ;IRaster pMaskraster = pRwks.OpenRasterDataset(pOraster.tif).CreateDefaultRaster();/获取掩膜的栅格数据IExtractionOp pEx = new RasterExtractionOpClass();IRaster pO = pEx.Raster(pRaster as IGeoDataset ,pMaskraster as IGeoDataset ) as IRaster ;ISaveAs pSA = pO as ISaveAs;/保存pSA.SaveAs(pp.tif ,pRwks as IWorkspace ,TIFF );通过圆来提取栅格数据：IWorkspaceFactory pWksfact = new RasterWorkspaceFactoryClass();IRasterWorkspace pRwks = pWksfact.OpenFromFile(F:Temp,0) as IRasterWorkspace ;IRaster2 pRaster = pRwks.OpenRasterDataset(cbers.tif).CreateDefaultRaster() as IRaster2;/获得待提取的栅格数据IRasterProps pRprops = pRaster as IRasterProps ;IWorkspaceFactory pShpwksfact = new ShapefileWorkspaceFactoryClass();IFeatureWorkspace pFwks = pShpwksfact.OpenFromFile(F:Temp, 0) as IFeatureWorkspace ;IFeatureClass pFclass = pFwks.OpenFeatureClass(mian);IFeatureCursor pFcur = pFclass.Search(null, false);IFeature pFeature = pFcur.NextFeature();IPolygon pPolygon = pFeature.Shape as IPolygon ;IArea pArea = pPolygon as IArea;IPoint pPoint = pArea.Centroid;/获得面的中心点。ICircularArc pCircular = new C