org html export with images

When we use org-html-export-to-html through the org-export interface, we generate html files for the corresponding org file. I use this feature fairly regularly, along with latex export, to share my research work and assignments. One hiccup I almost always face while sharing the html files is that the html file adds relative links to the image files that are a part of the org file which then requires me to share the images separately. Instead, if I can embed the images directly in the html file, then sharing just a self-contained file makes it much easier for me and my collaborators. To achieve this, I update the org-html--format-image function to put in the base64 coded string for the image in the image source link instead of adding a link to the image file.

(defun tob64 (filename)
  (base64-encode-string
   (with-temp-buffer
     (insert-file-contents filename)
     (buffer-string))))

(defun org-html--format-image (source attributes info)
  (org-html-close-tag
   "img"
   (org-html--make-attribute-string
    (org-combine-plists
     (list :src (format "data:image/png;base64,%s"
                        (tob64 source))
           :alt (if (string-match-p
                     (concat "^" org-preview-latex-image-directory) source)
                    (org-html-encode-plain-text
                     (org-find-text-property-in-string 'org-latex-src source))
                  (file-name-nondirectory source)))
     (if (string= "svg" (file-name-extension source))
         (org-combine-plists '(:class "org-svg") attributes '(:fallback nil))
       attributes)))
   info))