# White box and artifacts over the corner of a PNG image

I seem to have run into the same issue as described in this (previously closed) question.

\begin{figure}[ht]
\centering
\includegraphics[width=\columnwidth]{loop.png}
\caption{A 16-bit PNG image.}
\end{figure}


Here is the image being included:

Compilation succeeds without warning (pdflatex), but the resulting PDF shows artifacts and a white box in the corner of the image (when opened in Preview):

• could be some sort of transparent layer over the image. I don't see, how this is related to *TeX in any way... – naphaneal Jun 19 '18 at 9:21
• It is related to TeX because the PNG is fine when viewed in any software, and artifacts appear only after including it in a TeX document. – merlinND Jun 19 '18 at 9:22

For context, my original 16-bit PNG was the result of using convert on an EXR image, and so it took me a while to realize that it was 16-bit.