GDAL Create的问题

GDALAllRegister();
GDALDataset *poDstDS;
GDALDriver *poDriver ;
char **papszOptions2 = NULL ;
const char *pszFormat = "GTiff";
poDriver = GetGDALDriverManager()->GetDriverByName(pszFormat);
// ...............此处添加自己的代码，比如设定路径，要建立的文件长度、宽度之类的
CString strFullPath = "d:\\shiyasun.tif";
int nPicWidth = nBuffersizeX;
int nPicHeight = nBuffersizeY;

poDstDS = poDriver->Create( strFullPath, nPicWidth,nPicHeight,3, GDT_Byte, papszOptions2);
// ............此处添加代码，获取数据内容

(poDstDS->GetRasterBand(1))->RasterIO(GF_Write,0,0,nBuffersizeX,nBuffersizeY,pafScanblock[BandChoiceR],nBuffersizeX,nBuffersizeY,GDT_Byte,0,0);
(poDstDS->GetRasterBand(2))->RasterIO(GF_Write,0,0,nBuffersizeX,nBuffersizeY,pafScanblock[BandChoiceG],nBuffersizeX,nBuffersizeY,GDT_Byte,0,0);
(poDstDS->GetRasterBand(3))->RasterIO(GF_Write,0,0,nBuffersizeX,nBuffersizeY,pafScanblock[BandChoiceB],nBuffersizeX,nBuffersizeY,GDT_Byte,0,0);

nBUffersizeX = 512 nBuffersizeY = 512
调试的时候poDstDS = poDriver->Create( strFullPath, nPicWidth,nPicHeight,3, GDT_Byte, papszOptions2);
居然得到的poDstDS nRasterYSize = 3, nBands = 39491616 eAccess=512 不知道是哪里写错了 还请多指教 要是有GDAL对处理的数据存储的代码最好了

谢谢