Hi,

I have come up with a way to export subfigures to LaTeX (with the subfigure package) by
defining a new link type. The 'subcaption' of the subfigure would be the description of
the link. If we want to add parameters such as width, scale, etc., we can put them next
between the marks '>( ... )'

The code:

#+begin_src emacs-lisp
  (org-link-set-parameters
   "subfig"
   :follow (lambda (file) (find-file file))
   :face '(:foreground "chocolate" :weight bold :underline t)
   :display 'full
   :export (lambda (file desc backend)
	     (when (eq backend 'latex)
	       (if (string-match ">(\\(.+\\))" desc)
		   (concat "\\subfigure[" (replace-regexp-in-string "\s+>(.+)" "" desc) "]"
			   "{\\includegraphics"
			   "["
			   (match-string 1 desc)
			   "]"
			   "{"
			   file
			   "}}")
		 (format "\\subfigure[%s]{\\includegraphics{%s}}" desc file)))))
#+end_src

Example:

#+begin_src org
  ,#+CAPTION: Lorem impsum dolor
  ,#+ATTR_LaTeX: :options \centering
  ,#+begin_figure
  [[subfig:img1.jpg][Caption of img1 >(width=.3\textwidth)]]

  [[subfig:img2.jpg][Caption of img2 >(width=.3\textwidth)]]

  [[subfig:img3.jpg][Caption of img3 >(width=.6\textwidth)]]
  ,#+end_figure
#+end_src

Results:

#+begin_src latex
  \begin{figure}\centering
    \subfigure[Caption of img1]{\includegraphics[width=.3\textwidth]{img1.jpg}}

    \subfigure[Caption of img2]{\includegraphics[width=.3\textwidth]{img2.jpg}}

    \subfigure[Caption of img3]{\includegraphics[width=.6\textwidth]{img3.jpg}}
    \caption{Lorem impsum dolor}
  \end{figure}
#+end_src

If we want to export to HTML it would be something more tricky. In this case, the export
function could be like this (a width parameter would be enclosed between >{ ... }):

#+begin_src emacs-lisp
  (lambda (file desc backend)
    (cond
     ((eq backend 'latex)
      (if (string-match ">(\\(.+\\))" desc)
	  (concat "\\subfigure[" (replace-regexp-in-string "\s*>.+" "" desc) "]" "{\\includegraphics" "[" (match-string 1 desc) "]" "{"  file "}}")
	(format "\\subfigure[%s]{\\includegraphics{%s}}" (replace-regexp-in-string "\s*>.+" "" desc) file)))
     ((eq backend 'html)
      (if (string-match ">{\\(.+\\)}" desc)
	  (concat "<td><img src=\"" file "\" alt=\"" file "\"" " style=\"width:"
		  (match-string 1 desc)
		  "\""
		  "/><br>"
		  (replace-regexp-in-string "\s*&gt;.+" "" desc)
		  "</td>")
	(format "<td><img src=\"%s\" alt=\"%s\"/><br>%s</td>"
		file file
		(replace-regexp-in-string "\s*&gt;.+" "" desc))))))
#+end_src

Example:

#+begin_src org
  ,#+CAPTION: Lorem impsum dolor
  ,#+ATTR_LaTeX: :options \centering
  ,#+begin_figure
  @@html:<div class="org-center"><table style="margin-left:auto;margin-right:auto;"><tr>@@

  [[subfig:img1.jpg][Caption of img1 >(width=.3\textwidth) >{300px}]]

  [[subfig:img2.jpg][Caption of img2 >(width=.3\textwidth) >{300px}]]

  @@html:</tr></table><p> </p><table style="margin-left:auto;margin-right:auto;"><tr>@@

  [[subfig:img3.jpg][Caption of img3 >(width=.6\textwidth) >{600px}]]

  @@html:</tr></table><br>Lorem ipsum dolor</div>@@
  ,#+end_figure
#+end_src

As you can see, it is not the panacea, and you have to apply some direct format...

Happy holidays

Juan Manuel