docview issues on windows: pdf and png files

docview issues on windows: pdf and png files

[Vinh Nguyen]

Hi,

I am having issues with rendering pdf files using doc view on windows.
I downloaded emacs 24.3 windows binaries, have ghostscript installed
via cygwin (M-! gs confirms gs works), and placed libpng dll (libxpm,
jpeg, etc) in my emacs/bin directory (and installed via the setup
installation file). I’ve also installed these libraries using cygwin.
When I open an actual png file (ghostscript converts pdf to png, so
testing this), the image also does not render. I get this message:
“Cannot display image: (Invalid image specification)”.

Would appreciate if anyone could guide me to getting this to work on
windows. Thanks so much!

-- Vinh

Re: docview issues on windows: pdf and png files

[Eli Zaretskii]

> From: Vinh Nguyen <vinhdizzo@gmail.com>
> Date: Thu, 1 Aug 2013 18:50:21 -0700
> 
> I am having issues with rendering pdf files using doc view on windows.
> I downloaded emacs 24.3 windows binaries, have ghostscript installed
> via cygwin (M-! gs confirms gs works), and placed libpng dll (libxpm,
> jpeg, etc) in my emacs/bin directory (and installed via the setup
> installation file). I’ve also installed these libraries using cygwin.
> When I open an actual png file (ghostscript converts pdf to png, so
> testing this), the image also does not render. I get this message:
> “Cannot display image: (Invalid image specification)”.
> 
> Would appreciate if anyone could guide me to getting this to work on
> windows. Thanks so much!

What does this produce in Emacs:

  M-: (image-type-available-p 'png) RET

My guess is it says "nil", which means you don't have PNG image
support in your Emacs.

In a nutshell, don't mix a native Windows build of Emacs with Cygwin
libraries -- that will never work.  Even Cygwin Ghostscript could give
you trouble, when used from a native Windows Emacs.

If you want a Cygwin environment, install a Cygwin Emacs.  If you want
a native Windows environment, install native Windows image libraries
(see the file README.W32 for URLs) and a native Windows build of
Ghostscript.

Re: docview issues on windows: pdf and png files

[Vinh Nguyen]

Thanks for the response Eli.

I can confirm that if I use the emacs w32 in cygwin, with libpng
installed via cygwin, then doc-view does indeed work with pdf and png
files.

I can also confirm that in order for the compiled emacs 24.3 binaries
(available on gnu) to work with png and pdf files, then one would need
the libpng14-14.dll file in the emacs bin directory (I used an older
version of libpng before).

Thanks so much!
-- Vinh


On Thu, Aug 1, 2013 at 6:50 PM, Vinh Nguyen <vinhdizzo@gmail.com> wrote:
> Hi,
>
> I am having issues with rendering pdf files using doc view on windows.
> I downloaded emacs 24.3 windows binaries, have ghostscript installed
> via cygwin (M-! gs confirms gs works), and placed libpng dll (libxpm,
> jpeg, etc) in my emacs/bin directory (and installed via the setup
> installation file). I’ve also installed these libraries using cygwin.
> When I open an actual png file (ghostscript converts pdf to png, so
> testing this), the image also does not render. I get this message:
> “Cannot display image: (Invalid image specification)”.
>
> Would appreciate if anyone could guide me to getting this to work on
> windows. Thanks so much!
>
> -- Vinh