[luatex] png inclusion differs luatex vs pdftex

[Linas Stonys]

I get different colors of png image (attached europe.png) when I 
compile  lualatex and pdfflatex.
Image contains some "transparency group".
Differences are seen in acrobat but pdfxchange and sumatra shows the 
same (normaly like pdflatex did)
See attached wrong_image_diff.png.

Here's what one expert told me about pdfs with this  image:
"""
pdflatex inserts parameters dictionary 'Group' inside the page 
dictionary and luatex doesn't.
Acrobat precisely interprets all parameters that's why the view is 
different. Other viewers
work mach simpler and the view gets the same.
'transparency group' mast exists because image is with the 'soft mask' which
meant that image mast be painted with 'transparent imaging model'.
I guess that luatex  draws image with 'opaque imaging model'
"""

I hope you'll understand this comment (I translated it to english :))
Could luatex load png  like pdftex does?

Best,
Linas
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\documentclass{article}
\usepackage{graphicx}

\begin{document}



\begin{figure}[t]
  \includegraphics{europe.png}
\end{figure}

TEXT

\end{document}
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