wince下显示流式jpg图象

来源：互联网发布：室内设计师证书知乎编辑：程序博客网时间：2024/05/01 16:04

HBITMAP CImage::loadImgFile( CString &sFName)
{

int n_start=0,n_end=0;

GetPos(n_start,n_end,strFileName);
CString filename(L"test.jpg");//文件名
FILE* file = fopen(filename,"rb");
//获取文件长度
DWORD filelen =n_end-n_start;//m_file.GetLength()
CString str=L"^-^";
str.Format(L"%d",m_filelen);
//分配空间
HGLOBAL m_hglobal = GlobalAlloc(GMEM_MOVEABLE,filelen);

LPVOID pvdata = NULL;
//锁定堆空间,获取指向堆空间的指针
pvdata = GlobalLock(m_hglobal);
//将文件数据读区到堆中
m_file.Read(pvdata,m_filelen);
fread(pvdata, filelen, 1, file);
IStream* m_stream;
GlobalUnlock(m_hglobal);
//在堆中创建流对象
CreateStreamOnHGlobal(hglobal,TRUE,&m_stream);
CoInitializeEx(NULL,COINIT_MULTITHREADED);
IImagingFactory *pImgFactory =NULL;
IImage *pImage =NULL;
HBITMAP hResult =0;
    if   (SUCCEEDED(CoCreateInstance(CLSID_ImagingFactory,
                                     NULL,
                                     CLSCTX_INPROC_SERVER,
                                     IID_IImagingFactory,
                                     (void   **)&pImgFactory)))
{
ImageInfo imageInfo;
      //直接将流数据传进去
     if(SUCCEEDED(pImgFactory->CreateImageFromStream(m_stream,&pImage))
    // if(SUCCEEDED(pImgFactory->CreateImageFromFile(strFileName,&pImage))
     && SUCCEEDED(pImage->GetImageInfo(&imageInfo)))
        {
   CWindowDC dc(0);
   CDC dcBitmap;
   dcBitmap.CreateCompatibleDC(&dc);
   hResult =CreateCompatibleBitmap(dc.GetSafeHdc(),imageInfo.Width,imageInfo.Height);
   if(hResult){
    HGDIOBJ   hOldBitmap   =   dcBitmap.SelectObject(hResult);
                pImage->Draw(dcBitmap.GetSafeHdc(),CRect(0,0,imageInfo.Width,imageInfo.Height),NULL);
    dcBitmap.SelectObject(hOldBitmap);

   }
   pImage->Release();
        }

        pImgFactory->Release();

}
    CoUninitialize();

return hResult;
}