delphi 转 vc 有关问题

delphi 转 vc 问题
delphi 6.0:
code:
  Image.Picture.Bitmap.PixelFormat := pf24bit;
  Image.Picture.Bitmap.Width := w;
  Image.Picture.Bitmap.Height:= h;
  GetImageBuffer(pointer(Image.Picture.Bitmap.scanline[h-1]), 24); //**.dll里面的函数
  SaveImage(pointer(Image.Picture.Bitmap.scanline[h-1]), w,h, 24, pchar(filename)); //**.dll里的函数

vc6.0: (菜鸟改的gdi)
code:
bitmap.bmHeight=h;
bitmap.bmWidth=w;
bitmap.bmBitsPixel=24;

BYTE* buff=new BYTE[w*h];
m_yy->GetImageBuffer((BYTE*)bitmap.bmBits,24);
m_yy->SaveImage((BYTE*)bitmap.bmBits,w,h,24,"dao.jpg");

但是不行，请大侠分析下.

------解决方案--------------------
bitmap.bmHeight=h;
bitmap.bmWidth=w;
bitmap.bmBitsPixel=24;

BYTE* buff=new BYTE[w*h*3]; 
bitmap.GetBitmapBits(w * h * 3, buff);
m_yy->SaveImage(buff,w,h,24,"dao.jpg");