[Foundation-l] Experiment: Blurring all images on Wikipedia

Bjoern Hoehrmann derhoermi at gmx.net
Sat Oct 1 00:46:52 UTC 2011


  A while ago I made a bookmarklet that blurs images in articles on the
english Wikipedia and reveals them when the user hovers over the image.
I now had a chance to test this as a skin.js extension.


To try this out you would have to copy or import this code into your own
skin.js and skin.css files which are available e.g. under


This only works in recent desktop versions of Opera and Firefox and only
on devices where you can easily hover. It may show some images that it
ought to blur for boring reasons. Spoilers ahead if you want to try it.

Browsing around with that is quite interesting. Some findings: it is a
bit annoying when UI elements (say clipart in maintenance templates) are
blurred. The same goes for small logo-like graphics, say actual logos,
flags, coat of arms, and actual text, like rotated table headers. I did
expect that blurred maps would be annoying, but I've not found them to
be. Take http://en.wikipedia.org/wiki/Dagebüll as example, the marker
and text are overlayed so they are not blurred, and I can recognize the
shape of Germany fine.

I note that there is a perceptual problem if you click around to explore
how blurring affects the experience as that does not reflect what a user
would do. I noticed that my impression changed a lot when switching from
actually paying some attention to the articles to randomly moving to the
next article just looking at the images.

Pages, or parts of pages, that largely lack content (say all you get on
a screen is lone line of lead, table of contents, and image plus map on
the side, or a stub that has four sentences and an image). There it's a
bit odd, in stark contrast to an article like BDSM where I felt blurring
is very unobtrusive.

Another thing I've noticed is that I pay a whole lot more attention to
the images when I focus them, decide to hover over it, reveal it, and
then look at it, maybe read the caption and so on. I also noticed I do
not really bother to read the captions before I hover and rather decide
based on the blurred picture itself (I ignore most captions usually, so
this is unsurprising). There are also many surprises, where images do
not come out in the clear as you would have expected from the blur.

My impression is that it actually makes it much easier to think about if
an image is well placed where it is. If there are several images, you
can focus more easily on just the one, and you remove to some degree the
"status quo" effect, where you may be biased to agree with the placement
because someone already placed it there.

Images where red tones are used a lot seem to be rather distracting when
they are blurred. Blue and green and yellow and black and white and so
on are no problem, and the red tones are no problem when the image is
crisp. Not sure what's up with that, I have not noticed this before. It
would of course be possible to manipulate the colours in addition to the

Largely black and white bar charts and tree diagrams and illustrations
of data like them are also annoying when blurred, in part because there
is inconsistency as some of them are not blurred because they are made
not as image but using HTML constructs. They are perhaps too much like
text so unlike a photo with many different colors they are harder to
just ignore using one's banner blindness skills. There is also a noise
factor to this, http://en.wikipedia.org/wiki/Electromagnetic_induction
for instance compared to http://en.wikipedia.org/wiki/Morse_code -- in
the former the graphic in the infobox is fine blurred while the latter
irks me when blurred.

Generally though the added nuisance is hardly worth mentioning, it works
surprisingly well (well, this was the first thing I thought about when I
learned of the image filter, but it does work a bit better than I had
expected initially, and some issues would be easily fixed, like blurring
only images larger than 50x50 would take care of most of the UI graphics
for instance). So having conducted this experiment, I think the need to
have some images hidden while having others in the clear, where the com-
munity as a whole decided to show rather than hide, as in omitting them
for all users, is not a legitimate need.

Björn Höhrmann · mailto:bjoern at hoehrmann.de · http://bjoern.hoehrmann.de
Am Badedeich 7 · Telefon: +49(0)160/4415681 · http://www.bjoernsworld.de
25899 Dagebüll · PGP Pub. KeyID: 0xA4357E78 · http://www.websitedev.de/ 

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