GDAL遥感影像读取与显示-vc环境

GDAL是一个读写栅格和矢量空间数据的库，在GIS行业中有着巨大的应用，遥感影像是我们的空间数据的一种重要的类型，下面就给出遥感数据读取与显示的具体代码：

 char* szFileName = "K:\\各省市地图\\新建文件夹 (2)\\fuzhoucity.tif";
     GDALDataset *poDataset;   //GDAL数据集
     GDALAllRegister();

     poDataset = (GDALDataset*)GDALOpen(szFileName,GA_ReadOnly);
     if( poDataset == NULL )
     {
         AfxMessageBox(_T("文件打开失败!!!"));
         return;
     }

     GDALRasterBand *poBand1;   //遥感的一个波段
     GDALRasterBand *poBand2;
     GDALRasterBand *poBand3;
     int nBandCount = poDataset->GetRasterCount();
     poBand1 = poDataset->GetRasterBand(1);
     poBand2 = poDataset->GetRasterBand(2);
     poBand3 = poDataset->GetRasterBand(3);



     //获得图像显示窗口的尺寸
     GetClientRect(&m_ViewRect);

     int nImgSizeX = poDataset->GetRasterXSize();
     int nImgSizeY = poDataset->GetRasterYSize();

     //获得仿射变换的系数
     double adfGeoTransform[6];
     poDataset->GetGeoTransform( adfGeoTransform );

     double right  = adfGeoTransform[0] + nImgSizeX*adfGeoTransform[1];
     double bottom  = adfGeoTransform[3] + nImgSizeY*adfGeoTransform[5];

     int nBufferSizeX,nBufferSizeY;

     nBufferSizeX = nImgSizeX;
     nBufferSizeY = nImgSizeY;

     int nScrrenWidth = m_ViewRect.Width();
     int nScrrenHeight= m_ViewRect.Height();

     //为数据缓冲区分配内存
     BYTE *pafScanblock1,*pafScanblock2,*pafScanblock3,*TempLock1,*TempLock2,*TempLock3;
     pafScanblock1 = (BYTE *) CPLMalloc((nScrrenWidth)*(nScrrenHeight));
     pafScanblock2 = (BYTE *) CPLMalloc((nScrrenWidth)*(nScrrenHeight));
     pafScanblock3 = (BYTE *) CPLMalloc((nScrrenWidth)*(nScrrenHeight));
     TempLock1 = pafScanblock1;
     TempLock2 = pafScanblock2;
     TempLock3 = pafScanblock3;

     //读取数据
     poBand1->RasterIO( GF_Read, 0, 0,nBufferSizeX,nBufferSizeY,
         pafScanblock1,nScrrenWidth,nScrrenHeight, GDT_Byte,0, 0 );
     poBand2->RasterIO( GF_Read, 0, 0,nBufferSizeX,nBufferSizeY,
         pafScanblock2,nScrrenWidth,nScrrenHeight, GDT_Byte,0, 0 );
     poBand3->RasterIO( GF_Read, 0, 0,nBufferSizeX,nBufferSizeY,
         pafScanblock3,nScrrenWidth,nScrrenHeight, GDT_Byte,0, 0 );



     //在View逐点显示图像
     DWORD dwBytes = (nScrrenWidth * 24) / 8;
     while(((DWORD) dwBytes) % 4)
     {
         dwBytes++;
     }

     BYTE *szBuffer = new BYTE[nScrrenHeight*dwBytes];
     memset(szBuffer,0,nScrrenHeight*dwBytes);
     BYTE *pTemp = szBuffer;
     CClientDC dc(this);
     int nIndex = 0;
     for (int i=0;i<nScrrenHeight;i++)
     {
         for (int j=0;j<nScrrenWidth;j++)
         {

             BYTE dn1 = *pafScanblock1;
             BYTE dn2 = *pafScanblock2;
             BYTE dn3 = *pafScanblock3;

             //先绘制到内存DC中，而后再绘制到设备DC中
             dcMem.SetPixel(j,i,RGB(dn1,dn2,dn3)); //显示像素值

             pafScanblock1 ++;
             pafScanblock2 ++;
             pafScanblock3 ++;

         }

         szBuffer = pTemp+dwBytes*i;

     }

     pDC->BitBlt(0,0,m_ViewRect.Width(),m_ViewRect.Height(),&dcMem,0,0,
         SRCCOPY);

     CPLFree(TempLock1);
     CPLFree(TempLock2);
     CPLFree(TempLock3);

 

下面是遥感影像显示的效果：

这样显示效果就和ArcGIS打开的一样了。