Re: CImage read and write to memory files

From:

Pavel Pokutnev <pavel.pokutnev@googlemail.com>

Newsgroups:

microsoft.public.vc.mfc

Date:

Tue, 18 Aug 2009 04:01:21 -0700 (PDT)

Message-ID:

<6a4558aa-3689-498e-8da9-32b673c42e7b@b14g2000yqd.googlegroups.com>

On 18 Aug., 11:35, phil oakleaf <n...@oakleafsoftware.co.uk> wrote:

I am using the GDI+ Image class - but can change that to the MFC CImage
if need be.

At the moment I only seem to be able to save and load these to external
files.

Is there a way that I hold these images in a single block of memory
instead. That way I can store the memory in my own filing system.

Hope someone can help with this

many thanks
Phil

Here a sample for loading an image from resource, that might be
helpful:

BOOL LoadFromResource(HINSTANCE hInstance, LPCTSTR szResourceName,
LPCTSTR szResourceType, CImage& img)
{
  HRSRC hResource = ::FindResource(hInstance, szResourceName,
szResourceType);
  if (!hResource)
    return FALSE;

  DWORD imageSize = ::SizeofResource(hInstance, hResource);
  if (!imageSize)
    return FALSE;

  const void* pResourceData = ::LockResource(::LoadResource(hInstance,
hResource));
  if (!pResourceData)
    return FALSE;

  HGLOBAL hBuffer = ::GlobalAlloc(GMEM_MOVEABLE, imageSize);
  if (hBuffer)
  {
    HRESULT hr = E_FAIL;
    void* pBuffer = ::GlobalLock(hBuffer);
    if (pBuffer)
    {
      ::CopyMemory(pBuffer, pResourceData, imageSize);

      IStream* pStream = NULL;
      if (::CreateStreamOnHGlobal(hBuffer, FALSE, &pStream) == S_OK)
      {
        hr = img.Load(pStream);
        pStream->Release();
      }
      ::GlobalUnlock(hBuffer);
    }
    ::GlobalFree(hBuffer);
    hBuffer = NULL;
    return (hr == S_OK);
  }
  return FALSE;
}

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