[tex-live] tl2018: problems with including a (very specific) PNG file

[Ilya Zakharevich]

On Sun, Jun 24, 2018 at 09:50:47PM +0000, Karl Berry wrote:
>     The attached files build ���fine��� with tl2009, but produce a very bad
>     result with tl2018.
> 
> I don't get any difference in the output between 2009 and today (on
> x86-linux), but anyway, whatever is going on I believe is in the LaTeX
> drivers rather than the pdftex binary, because it worked normally with
> plain pdftex. So I posted here:
> https://github.com/latex3/graphics-def/issues/18

A lot of thanks!

> I surmise a workaround could be to open/save the png, or run through
> pngtopnm|pnmtopng, or whatever, since clearly that particular png is
> indeed "unusual". --best, karl.

Unfortunately, no.  This file is freshly generated by ImageMagick��s
convert.  This unfortunate property survives all the conversions���

  [ However, the file this image was ���convert���ed from may be indeed
    problematic.  It dates from the time of emTeX, which supported
    only, essentially, .PCX.  At the time, since (my?) graphing
    infrastructure was in infancy only, a wrong DPI value may have
    easily crept in. ]

Anyway, it is hours lost in debugging���镡�����and, apparently, not much can
be improved here���  A pity!

Thankfully, yours,
Ilya