bug#24669: 25.1; Cannot display images

[Drew Adams]

> If you are saying that your Emacs cannot display images, then my
> crystal ball says you didn't install the 64-bit image DLLs.  The ones
> you had before were 32-bit DLLs (because your Emacs was a 32-bit build
> back then), which the new 64-bit binary cannot use.
> 
> You can find the 64-bit DLLs here:
>   http://alpha.gnu.org/gnu/emacs/pretest/windows/emacs-25-x86_64-deps.zip

But I have no problem displaying images with this, or similar, 64-bit Emacs 
builds:

In GNU Emacs 25.0.50.1 (x86_64-w64-mingw32)
 of 2014-11-14 on KAEL
Repository revision: a5cbb7d9cc072db90201dd6e7e597c424a7d015e
Windowing system distributor `Microsoft Corp.', version 6.1.7601
Configured using:
 `configure --prefix=/z/emacs --host=x86_64-w64-mingw32
 --target=x86_64-w64-mingw32 --build=x86_64-w64-mingw32 --with-wide-int
 --with-jpeg --with-xpm --with-png --with-tiff --with-rsvg --with-xml2
 --with-gnutls --with-xft --with-sound=yes --with-file-notification=yes
 --without-dbus --without-imagemagick 'CFLAGS=-Ofast
 -fomit-frame-pointer -funroll-loops -g0 -pipe' 'CPPFLAGS=-DNDEBUG
 -DDBUS_STATIC_BUILD' 'LDFLAGS=-static-libgcc -static-libstdc++ -static
 -s -Wl,-s''

Why is it that other 64-bit Windows builds have no problem showing
images, but 25.1 cannot do so?  Presumably I have the requisite
binaries installed (though I don't recall where, and would have to
look for them).

Even if that were not the case, I would not want to install ALL of
that stuff (which I nevertheless downloaded), just to be able to
display images.  I already have other versions (e.g. Cygwin) of grep
etc.

Which, of that mountain of stuff, are the things supposedly needed
to (just) display images?  (If nothing else, that will help me find
the binaries that I already have installed, and which work with other
Emacs 64-bit builds - presumably some of the names are the same as
or similar to files in the zip you pointed to.)

Or is there some other, easy way to tell which binaries are being
used for images in the 64-bit builds I have where images are
displayed OK?  If (really) necessary, I'll install (only) the
necessary binaries from the new zip in the same location (or
similar, if some of the files names are exactly the same).