

The color of every photo on the internet blended together is orange - krazydad
http://www.theatlantic.com/technology/archive/2014/08/the-color-of-every-photo-on-the-internet-blended-together-is-orange/378614/

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qiqing
It's the color of incandescent bulbs, fire, and other popular sources of
light, reflected off of a large variety of surfaces.

~~~
egypturnash
This is pretty much what I was coming here to say.

Don't forget that we live under a yellow sun, too. There is a hell of a lot of
warm light in our world, natural and artificial.

~~~
MrRage
Sun is actually white... which is why you see a all the colors in a rainbow. I
know Superman lied to you. :)

~~~
trhway
Sun's radiation peak energy at sea level is around 500-600nm
[http://en.wikipedia.org/wiki/Sunlight#mediaviewer/File:Solar...](http://en.wikipedia.org/wiki/Sunlight#mediaviewer/File:Solar_Spectrum.png)

which is green

[http://en.wikipedia.org/wiki/Light#mediaviewer/File:Linear_v...](http://en.wikipedia.org/wiki/Light#mediaviewer/File:Linear_visible_spectrum.svg)

That is why grass/trees are green - they consume only the edges of the
spectrum (about 10-15% of the total sunlight coming through) bouncing the rest
back.

With respect to the original point about orange being average color of
Internet photos - keep in mind that most photos are produced by digital CCD
cameras which are more sensitive to orange/red than green/blue.

[http://www.gitthailand.com/image/ccd-
spectrum.jpg](http://www.gitthailand.com/image/ccd-spectrum.jpg)

~~~
tgb
Why does that explain why plants are generally green? If you had told me that
the energy peak was at X wavelength, I would have guessed that plants absorbed
most of that wavelength in order to not be wasteful rather than preferentially
reflecting that wavelength.

~~~
sbierwagen
Plants are actually pretty miserably inefficient at turning sunlight into
stored energy:
[http://en.wikipedia.org/wiki/Photosynthetic_efficiency](http://en.wikipedia.org/wiki/Photosynthetic_efficiency)
(not only do they reflect away most of the light, but photosynthesis isn't
linear at all graphed against light intensity: most of the noonday sun is
wasted)

There's no real consensus on why. (There's some wild guessing that green
photons might be too hot to handle: smashing fragile biomolecules apart rather
than powering them...
([http://scienceline.ucsb.edu/getkey.php?key=500](http://scienceline.ucsb.edu/getkey.php?key=500))
but then why does chlorophyll run fine on purple light?) You'd figure that
there would be incredible selection pressure on increasing photosynthesis
efficiency, but maybe they're stuck on a local maxima: it's not like a single
mutation can turn a C3 plant into a C4 plant:
[http://en.wikipedia.org/wiki/C4_photosynthesis](http://en.wikipedia.org/wiki/C4_photosynthesis)

------
nostromo
[http://www.chm.davidson.edu/vce/coordchem/spectrum.jpg](http://www.chm.davidson.edu/vce/coordchem/spectrum.jpg)

Orange is near the middle of the visible spectrum.

~~~
Strilanc
The averaging is happening in RGB space, not an HSV-esque space. There's no
obvious reason to expect the hue to end up averaged.

For example, the RGB average of red and blue is not orange; it's pink or
purple.

~~~
Tloewald
Actually the article is confused on this very point. I think it's actually
implied that it's sampled in HSV and not weighted for saturation or value.

Edit: his blog entry implies RGB, and it looks like the average color is
actually brownish grey, which would be highly unsurprising to anyone who has
mixed paint.

~~~
sp332
I just tried my own suggestion. For a random sampling of wavelengths from 390
to 700, I converted each to RGB using this function
[http://stackoverflow.com/a/3407960](http://stackoverflow.com/a/3407960) Then
I averaged the R, G, and B values. The result is 144, 122, 90 or #907A5A which
is... a dim brown color, with a "hue" of 36 which is very orange.

Edit: undid sRGB conversion since I think i did it wrong.

~~~
Tloewald
Good thought, and I think that the warm bias in digital cameras (and human
tastes) probably contributes as well.

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beejiu
I'm a little dubious about interpolating RGB values in that way -- I don't
think averaging the numbers directly maps to the real world colour mixing
you'd observe. I'd be interested in what the result is in Lab colour space.

~~~
klodolph
Ah, that's problematic.

The RGB color model is closely modeled after the physical phenomenon of light.
In a linear RGB color space, you can average two colors to get the same result
as if you had physically averaged those colors in the real world by combining
light.

However, L _a_ b is modeled after the subjective human perception of light and
color. L _a_ b is divorced from physical interpretations. Averaging colors in
L _a_ b does not have any real physical interpretation.

~~~
shkkmo
"The RGB color model is closely modeled after the physical phenomenon of
light."

Not actually true. RGB is modeled after the mechanism by which humans perceive
colors (using red, blue, and green photoreceptors).

If you mix Red and Blue light, you still only have Red and Blue light, but the
human perception system will perceive purple light, even though there is no EM
radiation at the 'purple' frequency.

~~~
klodolph
> Not actually true. RGB is modeled after the mechanism by which humans
> perceive colors (using red, blue, and green photoreceptors).

This is exactly the misconception I was talking about when I said that RGB is
modeled after physical processes and not after human perception. There is no
such thing as a red, green, or blue photoreceptor. There are three types of
cones: L, M, and S; there is also scotopic vision with its own response curve.
The L, M, and S cones respond to a gamut which cannot be reproduced with any
RGB system that uses real primaries. Or, put another way, no RGB system with
real primaries can specify all the colors we see.

Instead, RGB is a simulation of a physical system which uses three light
sources: red, green, and blue. That's all it is. For example, imagine that you
have three LEDs, or three phosphors, or three lasers. It doesn't matter. The
point is that RGB simulates these kinds of physical systems, not the systems
in the human eye.

On the other hand, L _a_ b and XYZ systems are modeled after the perception of
light. The experiments which lead to the creation of the XYZ color system had
subject participants match the color output of an RGB system with that of a
monochromatic light source. This experiment allowed us to use a well
understood color space (RGB) based on a physical process to test how human
vision worked.

~~~
shkkmo
I clearly misunderstood what you mean by "the physical phenomenon of light".

You seem to mean: "a common engineering method of displaying colors to the
human perceptual system"

while I thought you meant: "the physical properties of the visible band of the
electromagnetic spectrum"

~~~
klodolph
It's not like this question has a "right" answer, because we are describing
different models as "perceptual" or "physical".

The same phenomenon happens in audio. The vast majority of musical
synthesizers either model the perception of sound or the physical production
of sound. For example, you can model a piano as a physical system with a
vibrating string, or you can model it as a subjective phenomenon, constructing
a frequency spectrum that sounds similar using FM synthesis, subtractive
synthesis, additive synthesis, et cetera--none of which correspond in any
meaningful way to the piano itself, we're really trying to trick the ear.

In the same way, I see RGB as a simplified physical model rather than a
perceptual model, because it does correspond rather closely to physical
reality, and it corresponds somewhat poorly to subjective reality. You can
construct RGB as a simplification from a continuous spectrum model of
radiation, all you have to pick the spectrum of your primaries. From there,
you can use the RGB model in your physical simulations, such as ray tracing
and photon mapping. Lab color does not work well for ray tracers because it
does not correspond to physical reality: it is fairly nonlinear, and the
coordinate system is awkward.

Likewise, RGB is a poor model for subjective perception (compared to Lab or
XYZ) because its gamut is limited, and differences in RGB space do not
correspond well to differences in subjective qualities. You can see how
awkward RGB is for perceptual modeling whenever you use a color picker. It is
frustrating to try and construct a pleasing palette of colors by dragging
around RGB sliders, or even HSV/HSL sliders, because the model is so far from
subjective perception that doing something conceptually straightforward, such
as altering hue or matching luminosity, requires fiddling about.

In short, the description of RGB as a "physical model" is because we use it
for physical simulations, as well as for working with hardware such as
monitors and cameras. My description of Lab, CIECAM, XYZ, etc. as perceptial
models are because we use those for modeling the subjective perception of
color.

------
peter303
The color of the Universe is white-green according to this analysis:
[http://en.wikipedia.org/wiki/Cosmic_latte](http://en.wikipedia.org/wiki/Cosmic_latte)

~~~
sp332
_they soon corrected their analysis in a 2002 paper,[1] in which they reported
that their survey of the color of all light in the universe added up to a
slightly beigeish white._

------
willvarfar
Strange, I can't repeat the results on various folders I have.

I wrote a quick little (slow) Python script to compute a blended photo:
[https://gist.github.com/williame/92c7179d0963553d605f](https://gist.github.com/williame/92c7179d0963553d605f)

If a folder has some theme, such as a folder I have of a boat regatta, I get
an average picture that looks as you'd expect. So the code seems to average
correctly.

If I run it on a bigger assemblage of photos, I tend to get a uniform gray
though.

What am I doing wrong?

(I encourage you to try yourself!)

~~~
sp332
Maybe you should include lots of faces? And check that you're doing sRGB gamma
math correctly.
[http://http.developer.nvidia.com/GPUGems3/gpugems3_ch24.html](http://http.developer.nvidia.com/GPUGems3/gpugems3_ch24.html)

Edit: I'm guessing convert("RGB") means convert from whatever to linear RGB?
So that part should be fine.

~~~
willvarfar
And yet the article says its not to do with the colour of flesh etc..

~~~
sp332
_When someone told him that it was probably due to the colors of flesh in
photographs, he tried it with a pool of graffiti. Still orange._

Looks like there was only one test done explicitly without people.

------
spion
Here is a possible explanation: most digital camera makers tweak the color
balance towards warm rather than cool or neutral because consumers prefer
that.

------
Someone
looking at lists of RGB color names (e.g.
[http://cloford.com/resources/colours/500col.htm](http://cloford.com/resources/colours/500col.htm),
[http://www.keller.com/html-quickref/4a.html](http://www.keller.com/html-
quickref/4a.html),
[http://en.m.wikipedia.org/wiki/X11_color_names](http://en.m.wikipedia.org/wiki/X11_color_names))
I notice that everything called 'orange' has a blue component of zero.

So, this claim would imply that the average color in nature doesn't have a
blue component.

I guess the conclusion must be a) the sky is blue, and b) the majority of
photos on the internet does not show sky.

~~~
0x0
Also, the common rgb->greyscale algorithm has a very low factor for the blue
component (0.21 for r, 0.72 for g, 0.07 for b was one of the first on google)

------
freshbreath
I tried making a site to auto-blend images from Google Images…

[https://github.com/derv82/ImageBlender](https://github.com/derv82/ImageBlender)

[http://blen.derv.us](http://blen.derv.us)

Last time I checked, it didn't work 100%, and was laggy.

But I learned bootstrap in the process, and some of the quirks associated with
HTML5 canvas.

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diminish
i m using a ruby gem, color, to mix, blend colors. There are so many
parameters and methods you may use to blend 2 colors. So i think, you may
attain not only orange but other colors too deoending on how you blend

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roberjo
When you blend in 100M 'spacer.gif' images, it can skew the result.

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yvsong
I wonder what the average color of all web pages is, and that of all smart
phone app icons.

Edit: web pages should be weighted by page views, and app icons by downloads.

~~~
pariya
My guess is that the average smart phone app colour is blue.

------
rukittenme
We need to throw out the spray tan selfie outliers.

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svantana
I don't understand why it's presented as such a mystery? The average color
obviously exists, and if I had guessed it would be a reddish/yellowish gray
(due to the ubiquity of incandescent lighting, the non-UV-reflecting
properties of surfaces etc).

I was hoping to also see a covariance matrix, or maybe even a 3d histogram of
pixel colors on the web -- that would be interesting. This person is clearly
not a data scientist :)

~~~
krazydad
There's definitely some interesting things going on with human reasoning in
the way different people interpret the result. I originally assumed the images
would average to gray, but when I think about it logically, that would be kind
of miraculous. We wouldn't expect a bunch of photos taken on Mars to average
to gray (to be perfectly balanced in R, G and B), so why did I expect photos
taken on Earth to? It would mean all the colors are in a very precise balance,
which would be kind of odd.

With random images which include a few outdoor photos, there _is_ a noticeable
effect from the sky, but not as dramatic as I might expect - it tends to
produce a whitening, rather than a visible blue.

~~~
kaoD
The color is normalized. Before normalization, it _is_ gray :)

------
benhardy
Well thanks a LOT, John Boehner.

