static HRESULT DecodeImageFromThumbCache(IShellItem* pShellItem,
HBITMAP &thumbnail,
int cXY) {
// Read the bitmap from the thumbnail cache
IThumbnailCache* pThumbCache;
HRESULT hr = CoCreateInstance(CLSID_LocalThumbnailCache,
NULL,
CLSCTX_INPROC_SERVER,
IID_PPV_ARGS(&pThumbCache));
if (SUCCEEDED(hr)) {
ISharedBitmap* pBitmap = NULL;
hr = pThumbCache->GetThumbnail(pShellItem,
cXY,
WTS_EXTRACT | WTS_SCALETOREQUESTEDSIZE,
&pBitmap,
NULL,
NULL);
if (SUCCEEDED(hr) && pBitmap != NULL) {
hr = pBitmap->GetSharedBitmap(&thumbnail);
if (!SUCCEEDED(hr)) {
LOG_ERROR("Failed to get shared bitmap, result = %d", hr);
} else if (thumbnail == NULL) {
LOG_ERROR("Failed to get shared bitmap, thumbnail == NULL");
}
} else {
LOG_ERROR("Failed to get thumbnail, result = %d", hr);
}
pThumbCache->Release();
} else {
LOG_ERROR("Failed to create instance of IThumbnailCache, result = %d", hr);
}
return hr;
}
HRESULT CMainWindow::DecodeImageFromThumbCache(
IShellItem *pShellItem,
ID2D1Bitmap **ppBitmap
)
{
const UINT THUMB_SIZE = 256;
// Read the bitmap from the thumbnail cache
IThumbnailCache *pThumbCache;
HRESULT hr = CoCreateInstance(
CLSID_LocalThumbnailCache,
NULL,
CLSCTX_INPROC_SERVER,
IID_PPV_ARGS(&pThumbCache)
);
if (SUCCEEDED(hr))
{
ISharedBitmap *pBitmap;
hr = pThumbCache->GetThumbnail(
pShellItem,
THUMB_SIZE,
WTS_SCALETOREQUESTEDSIZE,
&pBitmap,
NULL,
NULL
);
if (SUCCEEDED(hr))
{
HBITMAP hBitmap;
hr = pBitmap->GetSharedBitmap(
&hBitmap
);
if (SUCCEEDED(hr))
{
// Create a WIC bitmap from the shared bitmap
IWICImagingFactory *pFactory;
hr = CoCreateInstance(
CLSID_WICImagingFactory,
NULL,
CLSCTX_INPROC_SERVER,
IID_PPV_ARGS(&pFactory)
);
if (SUCCEEDED(hr))
{
IWICBitmap *pWICBitmap;
hr = pFactory->CreateBitmapFromHBITMAP(
hBitmap,
NULL,
WICBitmapIgnoreAlpha,
&pWICBitmap
);
if (SUCCEEDED(hr))
{
// Create a D2D bitmap from the WIC bitmap
hr = m_pRenderTarget->CreateBitmapFromWicBitmap(
pWICBitmap,
NULL,
ppBitmap
);
pWICBitmap->Release();
}
pFactory->Release();
}
}
pBitmap->Release();
}
pThumbCache->Release();
}
return hr;
}