Base 64 inline images in html export

Base 64 inline images in html export

[Greg Sexton]

Hi,

I did find a post about this from around 2009 but I'm not sure it went
anywhere. It's very useful for me to be able to export a single html
file that I can distribute around. Base 64 encoding images directly in
to the exported html makes this possible.

The feature seems fairly well supported by browsers these days.[1]

I've hacked up this ugly proof of concept. I guess it wouldn't take too
much to productionize this and make the behavior configurable. Any
thoughts?

--8<---------------cut here---------------start------------->8---
(defun gs/b64-img (file-uri)
  (let ((file (s-replace "file://" "" file-uri)))
    (if (f-exists? file)
        ;; src="data:image/png;base64,iVBORw0KGgoAAAANSUh..."
        (s-concat "data:image/"
                  (f-ext file)
                  ";base64,"
                  (base64-encode-string (f-read-bytes file)))
      file-uri)))

(defun org-html--format-image (source attributes info)
  "Return \"img\" tag with given SOURCE and ATTRIBUTES.
SOURCE is a string specifying the location of the image.
ATTRIBUTES is a plist, as returned by
`org-export-read-attribute'.  INFO is a plist used as
a communication channel."
  (org-html-close-tag
   "img"
   (org-html--make-attribute-string
    (org-combine-plists
     (list :src (gs/b64-img source)   ; <-- interesting line is here
           :alt (if (string-match-p "^ltxpng/" source)
                    (org-html-encode-plain-text
                     (org-find-text-property-in-string 'org-latex-src source))
                  (file-name-nondirectory source)))
     attributes))
   info))
--8<---------------cut here---------------end--------------->8---


[1]: http://stackoverflow.com/questions/1207190/embedding-base64-images

-- 
 Greg



Amazon Development Centre (London) Ltd. Registered in England and Wales with registration number 04543232 and which has its registered office at Leadenhall Court, One Leadenhall Street, London EC3V 1PP, United Kingdom.

Re: Base 64 inline images in html export

[Rasmus]

Hi Greg,

Thanks for your patch.

Do you intend to finish the patch for inclusion in Org?  If so please have
a look at:

    http://orgmode.org/worg/org-contribute.html
    
In particular, you need to assign the copyright of your changes to FSF.
You might also want to familiarize yourself with how comments are done in
Emacs.  In particular, they should be prose and informative.

Greg Sexton <gsexton@amazon.co.uk> writes:

> I've hacked up this ugly proof of concept. I guess it wouldn't take too
> much to productionize this and make the behavior configurable. Any
> thoughts?

I think it would be great.  But how about external pictures?  It seems
these will not work with your patch.  How about SVGs in external files?

If your goal if a self-containing html what about external JS and CSS?

> (defun gs/b64-img (file-uri)
>   (let ((file (s-replace "file://" "" file-uri)))
>     (if (f-exists? file)

This does not warrant new 

>         ;; src="data:image/png;base64,iVBORw0KGgoAAAANSUh..."

I don’t get the point of this comment.

>         (s-concat "data:image/"
>                   (f-ext file)
>                   ";base64,"
>                   (base64-encode-string (f-read-bytes file)))
>       file-uri)))



> (defun org-html--format-image (source attributes info)
>   "Return \"img\" tag with given SOURCE and ATTRIBUTES.
> SOURCE is a string specifying the location of the image.
> ATTRIBUTES is a plist, as returned by
> `org-export-read-attribute'.  INFO is a plist used as
> a communication channel."

You are removing features from an existing function.

>   (org-html-close-tag
>    "img"
>    (org-html--make-attribute-string
>     (org-combine-plists
>      (list :src (gs/b64-img source)   ; <-- interesting line is here

The comment is no good.

>            :alt (if (string-match-p "^ltxpng/" source)
>                     (org-html-encode-plain-text
>                      (org-find-text-property-in-string 'org-latex-src source))
>                   (file-name-nondirectory source)))
>      attributes))
>    info))

Rasmus

-- 
Not everything that goes around comes back around, you know

Re: Base 64 inline images in html export

[Grant Rettke]

Since you too are exploring packaging, this might give you some test:

http://kitchingroup.cheme.cmu.edu/blog/2014/03/05/Creating-a-transportable-zip-archive-of-an-org-file/
Sincerely,

Grant Rettke


On Mon, Dec 7, 2015 at 6:15 AM, Greg Sexton <gsexton@amazon.co.uk> wrote:
> Hi,
>
> I did find a post about this from around 2009 but I'm not sure it went
> anywhere. It's very useful for me to be able to export a single html
> file that I can distribute around. Base 64 encoding images directly in
> to the exported html makes this possible.
>
> The feature seems fairly well supported by browsers these days.[1]
>
> I've hacked up this ugly proof of concept. I guess it wouldn't take too
> much to productionize this and make the behavior configurable. Any
> thoughts?
>
> --8<---------------cut here---------------start------------->8---
> (defun gs/b64-img (file-uri)
>   (let ((file (s-replace "file://" "" file-uri)))
>     (if (f-exists? file)
>         ;; src="data:image/png;base64,iVBORw0KGgoAAAANSUh..."
>         (s-concat "data:image/"
>                   (f-ext file)
>                   ";base64,"
>                   (base64-encode-string (f-read-bytes file)))
>       file-uri)))
>
> (defun org-html--format-image (source attributes info)
>   "Return \"img\" tag with given SOURCE and ATTRIBUTES.
> SOURCE is a string specifying the location of the image.
> ATTRIBUTES is a plist, as returned by
> `org-export-read-attribute'.  INFO is a plist used as
> a communication channel."
>   (org-html-close-tag
>    "img"
>    (org-html--make-attribute-string
>     (org-combine-plists
>      (list :src (gs/b64-img source)   ; <-- interesting line is here
>            :alt (if (string-match-p "^ltxpng/" source)
>                     (org-html-encode-plain-text
>                      (org-find-text-property-in-string 'org-latex-src source))
>                   (file-name-nondirectory source)))
>      attributes))
>    info))
> --8<---------------cut here---------------end--------------->8---
>
>
> [1]: http://stackoverflow.com/questions/1207190/embedding-base64-images
>
> --
>  Greg
>
>
>
> Amazon Development Centre (London) Ltd. Registered in England and Wales with registration number 04543232 and which has its registered office at Leadenhall Court, One Leadenhall Street, London EC3V 1PP, United Kingdom.
>
>

Re: Base 64 inline images in html export

[John Kitchin]

[-- Attachment #1: Type: text/plain, Size: 2976 bytes --]

I can't recall if I pointed to this post before:
http://kitchingroup.cheme.cmu.edu/blog/2015/05/09/Another-approach-to-embedding-org-source-in-html/

but it is similar to what you are trying to do.

John

-----------------------------------
Professor John Kitchin
Doherty Hall A207F
Department of Chemical Engineering
Carnegie Mellon University
Pittsburgh, PA 15213
412-268-7803
@johnkitchin
http://kitchingroup.cheme.cmu.edu


On Tue, Dec 22, 2015 at 8:48 PM, Grant Rettke <gcr@wisdomandwonder.com>
wrote:

> Since you too are exploring packaging, this might give you some test:
>
>
> http://kitchingroup.cheme.cmu.edu/blog/2014/03/05/Creating-a-transportable-zip-archive-of-an-org-file/
> Sincerely,
>
> Grant Rettke
>
>
> On Mon, Dec 7, 2015 at 6:15 AM, Greg Sexton <gsexton@amazon.co.uk> wrote:
> > Hi,
> >
> > I did find a post about this from around 2009 but I'm not sure it went
> > anywhere. It's very useful for me to be able to export a single html
> > file that I can distribute around. Base 64 encoding images directly in
> > to the exported html makes this possible.
> >
> > The feature seems fairly well supported by browsers these days.[1]
> >
> > I've hacked up this ugly proof of concept. I guess it wouldn't take too
> > much to productionize this and make the behavior configurable. Any
> > thoughts?
> >
> > --8<---------------cut here---------------start------------->8---
> > (defun gs/b64-img (file-uri)
> >   (let ((file (s-replace "file://" "" file-uri)))
> >     (if (f-exists? file)
> >         ;; src="data:image/png;base64,iVBORw0KGgoAAAANSUh..."
> >         (s-concat "data:image/"
> >                   (f-ext file)
> >                   ";base64,"
> >                   (base64-encode-string (f-read-bytes file)))
> >       file-uri)))
> >
> > (defun org-html--format-image (source attributes info)
> >   "Return \"img\" tag with given SOURCE and ATTRIBUTES.
> > SOURCE is a string specifying the location of the image.
> > ATTRIBUTES is a plist, as returned by
> > `org-export-read-attribute'.  INFO is a plist used as
> > a communication channel."
> >   (org-html-close-tag
> >    "img"
> >    (org-html--make-attribute-string
> >     (org-combine-plists
> >      (list :src (gs/b64-img source)   ; <-- interesting line is here
> >            :alt (if (string-match-p "^ltxpng/" source)
> >                     (org-html-encode-plain-text
> >                      (org-find-text-property-in-string 'org-latex-src
> source))
> >                   (file-name-nondirectory source)))
> >      attributes))
> >    info))
> > --8<---------------cut here---------------end--------------->8---
> >
> >
> > [1]: http://stackoverflow.com/questions/1207190/embedding-base64-images
> >
> > --
> >  Greg
> >
> >
> >
> > Amazon Development Centre (London) Ltd. Registered in England and Wales
> with registration number 04543232 and which has its registered office at
> Leadenhall Court, One Leadenhall Street, London EC3V 1PP, United Kingdom.
> >
> >
>
>

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