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procedure TCustomBitmap32.LoadFromFile(const FileName: string);
var P: TPicture;
begin
   /// [ ... ]
  // if we got here, use the fallback approach via TPicture...
  P := TPicture.Create;
  try
    P.LoadFromFile(FileName);
    Assign(P);
  finally
    P.Free;
  end;
end;					

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function ScalePicStreamToFile(aStream: TStream; aFilename: UnicodeString; destWidth, destHeight: Integer; aWICImagingFactory: IWICImagingFactory; OverWrite: Boolean = False): boolean;
var
    hr: HRESULT;
    isLocalFactory: Boolean;
    // for proper scaling
    xfactor, yfactor:double;
    origWidth, origHeight: Cardinal;
    newWidth, newHeight: Cardinal;
    // reading the source image
    SourceAdapter: IStream;
    BitmapDecoder: IWICBitmapDecoder;
    DecodeFrame: IWICBitmapFrameDecode;
    SourceBitmap: IWICBitmap;
    SourceScaler: IWICBitmapScaler;
    // writing the resized image
    DestStream: TMemoryStream;
    DestAdapter: IStream;
    DestWICStream: IWICStream;
    BitmapEncoder: IWICBitmapEncoder;
    EncodeFrame: IWICBitmapFrameEncode;
    Props: IPropertyBag2;
begin
    result := False;
    if Not Overwrite and FileExists(aFilename) then
    begin
        result := True;
        exit;
    end;

    isLocalFactory := (aWICImagingFactory = nil);
    if isLocalFactory then
        CoCreateInstance(CLSID_WICImagingFactory, nil, CLSCTX_INPROC_SERVER or
          CLSCTX_LOCAL_SERVER, IUnknown, aWICImagingFactory);

    // read the image data from stream
    SourceAdapter := TStreamAdapter.Create(aStream);
    hr := aWICImagingFactory.CreateDecoderFromStream(SourceAdapter, guid_null, WICDecodeMetadataCacheOnDemand, BitmapDecoder);
    if Succeeded(hr) then hr := BitmapDecoder.GetFrame(0, DecodeFrame);
    if Succeeded(hr) then hr := aWICImagingFactory.CreateBitmapFromSource(DecodeFrame, WICBitmapCacheOnLoad, SourceBitmap);
    if Succeeded(hr) then hr := SourceBitmap.GetSize(origWidth, origHeight);

    // calculate proper scaling
    xfactor:= (destWidth) / origWidth;
    yfactor:= (destHeight) / origHeight;
    if xfactor > yfactor then
    begin
        newWidth := round(origWidth * yfactor);
        newHeight := round(origHeight * yfactor);
    end else
    begin
        newWidth := round(origWidth * xfactor);
        newHeight := round(origHeight * xfactor);
    end;

    // scale the original image
    if Succeeded(hr) then hr := aWICImagingFactory.CreateBitmapScaler(SourceScaler);
    if Succeeded(hr) then hr := SourceScaler.Initialize(SourceBitmap, NewWidth, NewHeight, WICBitmapInterpolationModeFant);

    if Succeeded(hr) then
    begin
        // Reading and scaling the original image was successful.
        // Now try to save the scaled image
        DestStream := TMemoryStream.create;
        try
            // create new WICStream
            DestAdapter := TStreamAdapter.Create(DestStream);
            if Succeeded(hr) then hr := aWICImagingFactory.CreateStream(DestWICStream);
            if Succeeded(hr) then hr := DestWICStream.InitializeFromIStream(DestAdapter);
            // create and prepare JPEG-Encoder
            if Succeeded(hr) then hr := aWICImagingFactory.CreateEncoder(GUID_ContainerFormatJpeg, guid_null, BitmapEncoder);
            if Succeeded(hr) then hr := BitmapEncoder.Initialize(DestWICStream, WICBitmapEncoderNoCache);
            if Succeeded(hr) then hr := BitmapEncoder.CreateNewFrame(EncodeFrame, Props);
            if Succeeded(hr) then hr := EncodeFrame.Initialize(Props);
            if Succeeded(hr) then hr := EncodeFrame.SetSize(newWidth, newHeight);
            // write image data
            if Succeeded(hr) then hr := EncodeFrame.WriteSource(SourceScaler, nil);
            if Succeeded(hr) then hr := EncodeFrame.Commit;
            if Succeeded(hr) then hr := BitmapEncoder.Commit;
            // finally save the stream to the destination file
            if Succeeded(hr) then
                try
                    DestStream.SaveToFile(aFilename);
                    result := True;
                except
                    // silent exception here, but (try to) delete the destination file, if it exists
                    result := False; 
                    if FileExists(aFilename) then DeleteFile(aFilename);
                end;
        finally
            DestStream.Free;
        end;
    end;

    if isLocalFactory then
        aWICImagingFactory._Release;
end;