virtual HRESULT STDMETHODCALLTYPE Initialize(
    [IN] __RPC__in_opt IWICBitmapSource *pISource,
    [IN] __RPC__in REFWICPixelFormatGUID dstFormat,
    [IN] WICBitmapDitherType dither,
    [IN] IWICPalette *pIPalette,
    [IN] double alphaThresholdPercent,
    [IN] WICBitmapPaletteType paletteTranslate);