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;
}
示例#2
0
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;
}