ArcGIS Engine 10 开发手册(8-8)示例：改变栅格数据像素的值

    本文通过代码演示如何改变栅格数据像素的值。

    示例代码

public void ChangeRasterValue (IRasterDataset2 pRasterDatset)

{

  IRaster2 pRaster2 = pRasterDatset.CreateFullRaster () as IRaster2;

  IPnt pPntBlock = new PntClass ();

  pPntBlock.X = 128;

  pPntBlock.Y = 128;

  IRasterCursor pRasterCursor = pRaster2.CreateCursorEx (pPntBlock);

  IRasterEdit pRasterEdit = pRaster2 as IRasterEdit;

  if (pRasterEdit.CanEdit ())

  {

    IRasterBandCollection pBands = pRasterDatset as IRasterBandCollection;

    IPixelBlock3 pPixelblock3 = null;

    int pBlockwidth = 0;

    int pBlockheight = 0;

    System.Array pixels;

    IPnt pPnt = null;

    object pValue;

    long pBandCount = pBands.Count;

    //获取Nodata

    //IRasterProps pRasterPro = pRaster2 as IRasterProps;

    //object pNodata = pRasterPro.NoDataValue;

    do

    {

      pPixelblock3 = pRasterCursor.PixelBlock as IPixelBlock3;

      pBlockwidth = pPixelblock3.Width;

      pBlockheight = pPixelblock3.Height;

      for (int k = 0; k < pBandCount; k++)

      {

        pixels = (System.Array) pPixelblock3.get_PixelData (k);

        for (int i = 0; i < pBlockwidth; i++)

        {

          for (int j = 0; j < pBlockheight; j++)

          {

            pValue = pixels.GetValue (i, j);

            if (Convert.ToInt32 (pValue) == 0)

            {

              pixels.SetValue (Convert.ToByte (50), i, j);

            }

          }

        }

        pPixelblock3.set_PixelData (k, pixels);

      }

      pPnt = pRasterCursor.TopLeft;

      pRasterEdit.Write (pPnt,(IPixelBlock) pPixelblock3);

    }

    while (pRasterCursor.Next ());

    System.Runtime.InteropServices.Marshal.ReleaseComObject (pRasterEdit);

  }

}

    处理结果

    原始影像图：

    处理后的影像图：