orgmode - inline image resize not happen

Question

I have installed emacs 25.3.1 ("GNU Emacs 25.3.1 (x86_64-w64-mingw32)of 2017-09-26) and Imagemagick-6.8.8 on windows10. when I try below orgmode document (The tiger png file is downloaded here:

#+ATTR_HTML: :width 600px
[[./tiger.png]]

The displayed image still very small (resize not happen):

And below variable all nil:

#+BEGIN_SRC elisp :results output
(print org-image-actual-width)
(print (image-type-available-p 'imagemagick))
#+END_SRC

#+RESULTS:
: 
: nil
: 
: nil

Not sure if emacs still support imagemagick!

Answer 1

To see if your Emacs supports imagemagick check the variable system-configuration-features. If the value contains the entry IMAGEMAGICK, you should be OK.

In any case, to resize images within org mode you don't set an HTML attribute, but rather an ORG attribute, as in:

#+ATTR_ORG: :width 600px
[[./tiger.png]]

You can also specify a default value to image sizes by changing the variable org-image-actual-width.