[HN Gopher] Color appearance and the end of Hering's Opponent-Co...
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Color appearance and the end of Hering's Opponent-Colors theory
Author : bookofjoe
Score : 76 points
Date : 2023-07-09 15:33 UTC (7 hours ago)
(HTM) web link (www.cell.com)
(TXT) w3m dump (www.cell.com)
| weinzierl wrote:
| I think it is important to point out that this essay only claims
| that Hering's theory and general concepts of color opponency and
| cone opponency is wrong and not the idea of opponent colors in
| general.
|
| _" Proof of color opponency was established decades before
| Hering, with the discovery of complementary-color pairs and color
| afterimages [29.,30.]; color opponency is implemented by retinal
| cone-opponent neurons [22.]. Trichromacy and complementarity
| organize colorimetric space [31.], and Hering's theory can be
| discarded without threatening these well-established
| principles."_
| parpfish wrote:
| Their first sentence is:
|
| > The essay reviews the psychological and physiological
| evidence for Opponent-Colors Theory and concludes the theory is
| wrong.
|
| Am I supposed to interpret "Opponent-Colors Theory" as
| something specific and different from the general concept of
| opponent colors?
| weinzierl wrote:
| I think so. They seem to distinguish between _" Hering's
| Opponent Colors (the unique hues)"_ and _" Hering's theory
| (the linking proposition)"_.
|
| They only attack Hering's theory = the linking proposition.
| parpfish wrote:
| good to see that the difficulty naming things isn't unique
| to programming
| boredemployee wrote:
| Well. That's crazy.
|
| Auto industry is all based in the opponent-colors theory, imagine
| convincing thousands of people that the problems and fines
| involving color quality control were wrong all along.
| weinzierl wrote:
| From what I understand are they not rejecting all of it, just
| the parts that hypothesized how things work in brain. These
| parts are hard to verify and I believe the essay claims that
| these parts have been falsified by now and it proposes an
| alternative hypothesis.
| OscarCunningham wrote:
| I'm not following this bit from box 1.
|
| > Objective tests of Opponent-Colors Theory became possible when
| the theory was formulated as a hypothesis about how cone signals
| are transmitted to perception. The formal exposition spells out
| the mathematical transformation of cone responses to opponent-
| color pairs; baked into the math is the linearity of Opponent-
| Colors Theory implied by the description of color appearances as
| simple (mathematical) combinations of red-versus-green, yellow-
| versus-blue, and black-versus-white
|
| Why does the fact that colour appearance can be described in
| terms of the unique hues imply that the representation must be
| linear?
| weinzierl wrote:
| This is a good question and I'm also not quite sure what to
| make of it. As no one has answered this for a while I'll give
| it a shot, even at the risk of being wrong.
|
| I think that what they are saying is that linearity is part of
| the status quo of Opponent-Colors Theory and they reject the
| whole thing including the linearity. So in essence they agree
| with you.
| masswerk wrote:
| Hasn't this been established for long by references to antique
| color names (both Greek and Roman), as well as the representation
| of spectra in African languages? While the article makes
| reference to Greek semantics and anthropological findings, it
| still presents this as something new, where it should have
| emphasized the underlying theory.
| adrian_b wrote:
| This essay should not have discussed anything about the names
| used for colors in various languages, because the number of
| color names that exist in a language has a very loose
| relationship with the psychological perception of colors, so it
| cannot be used to prove anything about the validity or
| invalidity of Hering's theory.
|
| In all languages, the circle of hues is partitioned in a number
| of regions, which have distinct names. The number of these
| regions varies from language to language, usually between two
| and eight. The value of this number has much less to do with
| the distinctiveness of the colors, than with the necessity of
| describing the colors of the objects that had a high
| probability of being subjects of conversation for the speakers
| of that language. Many languages have a single word for the
| colors green, blue-green and blue, just because there were no
| common objects for which it was necessary to specify whether
| they were green or blue.
|
| The too much repeated myth that the Ancient Greeks did not have
| a word for blue was created by people who might have known some
| linguistics, but who were ignorant about chemistry and
| mineralogy.
|
| There are plenty of dictionaries and commentaries about Ancient
| Greek literature which are very wrong about many words, because
| their authors did not understand what they have read, for lack
| of knowledge about the natural sciences. For instance, when
| Homer speaks about "miltos" used to paint some ships, you must
| understand that this word designates what is now called
| hematite or ferric oxide, which was processed as a red pigment.
| Or else when Plato speaks about the grains of diamond found
| together with alluvial gold, that has nothing to do with what
| is now named diamond (which became known to the Greeks only
| later, after the expeditions of Alexander the Great), but
| "diamond" was the name for nuggets of native osmium-iridium-
| ruthenium alloy. Understanding this meaning makes clear why
| Hesiod said several times that diamond is gray and why he
| considered it as a material from which a blade could be forged
| by someone with superhuman strength.
|
| There are many references to blue in Ancient Greek literature
| and the normal word that was used has been borrowed in English
| as "cyan". "Cyan" has never meant blue-green in Greek, but only
| plain blue. "Cyan" initially meant the color of the painting
| pigment that is now called "ultramarine blue", but later it was
| also used for the cheaper blue pigments Egyptian blue and
| azurite. An alternative way to refer to blue in Greek was as
| the "color of the air", which meant the color of the sky.
|
| In Latin, blue was normally called as the color of the sky,
| while the word used for green, "viridis" meant either green or
| blue-green. When these two colors had to be distinguished, the
| former was described as green like leaves or like grass or like
| emeralds, while the latter was described as green like the
| littoral sea or like turquoise or like beryls.
|
| Similarly, the word used for red in Latin (and also in Greek)
| meant either red or purple, and when the two colors had to be
| distinguished, the former was described as red like the dye
| extracted from beetles (crimson), while the latter was
| described as red like the dye extracted from marine snails.
| Syzygies wrote:
| As a mathematician I'm hypersensitive to people overreaching with
| theory. It's often the King's clothes. There are indisputable
| reasons why a musical fifth sounds good, but vision is more
| organic. Evolution has left us with many layers of color
| perception, like an out-of-control code base. Sure, anything can
| be fit to a model if we ignore the parts that don't fit; that's
| how theory intoxicates.
|
| My father devised the "Bayer filter" for digital photography, and
| favored green for practical reasons that have stood the test of
| time. There is some theory that applies here, it's just not the
| same as harmonics and sound.
|
| I'd love to code up a machine learning project that showed the
| user many color combinations, responding to feedback. Willem de
| Kooning for example painted with an extraordinarily original
| palette. Could we tailor our own color palettes, with an AI
| assist?
| beardyw wrote:
| > There are indisputable reasons why a musical fifth sounds
| good, but vision is more organic.
|
| Once could argue that our eyes can't even "hear" a fifth. The
| amount of data our ears extract out of basically two points is
| amazing. Our eyes in the meantime take an entire spectrum and
| come up with "blue-ish".
| waveBidder wrote:
| I think you're pointing at the fact that there are only three
| kinds of cones, whereas the ear has ... well honesty I'm not
| sure how many different kinds of hair cell there are.
| apparently [16,000](https://www.nih.gov/news-events/nih-
| research-matters/hearing...)!
|
| the eyes are much better at directionality though; probably
| some kind of trade-off going on there.
| OscarCunningham wrote:
| Well it's position vs frequency, so a tradeoff is forced by
| the Heisenberg uncertainty principle. I don't know if
| either system is actually reaching this limit though.
| waveBidder wrote:
| I thought about that, but you could just cram more cells
| to get higher resolution. Reflecting a bit more, hair
| cells vary by length, whereas each new cone requires a
| unique protein, so I'd expect hearing to respond to more
| easily to evolutionary pressures.
| jfengel wrote:
| All theory is overreaching. It's called the Problem of
| Induction. All you can do is hypothesize, test, and revise.
| Mathematicians will never be happy about it.
|
| It will always be worse the more complicated something is. One
| particle is hard. A hydrogen atom is harder. Oxygen is just
| this side of impossible. Molecules are impossible and you just
| start throwing away vast numbers of terms. By the time you get
| to an eyeball, much less a brain, you are basically just
| guessing and hoping you can cover some of the cases some of the
| time.
| manmal wrote:
| > hypersensitive to people overreaching with theory
|
| What's left of the scientific method if people don't? I think
| reproducibility and inertia (,,science progresses one death at
| a time") are problems, but I hadn't thought that induction
| could be one.
| robomartin wrote:
| > I'd love to code up a machine learning project that showed
| the user many color combinations
|
| That would be fine, so long as you don't use an RGB display to
| display those colors.
|
| The RGB color space is severely limited when compared to the
| colors a person can see. This becomes obvious as one plots
| color spaces on a CIE 1931 diagram.
|
| Here's a simple tool to see some of this (recommendation: move
| "system gamut contrast" slider to 50%). Select a working color
| space from the pulldown to see how much of the visible range it
| encloses (or discards).
|
| https://demonstrations.wolfram.com/CIEChromaticityDiagram/
|
| A typical REC709 color space throws away over half the colors a
| person can see. In other words, as I said, using a monitor to
| run color experiments can be a serious mistake. Color Science
| can be strangely complex.
|
| There is a company trying to push the envelope in display
| technology and encourage industry to move primaries beyond RGB.
| The results, based on prototypes, can be impressive:
|
| https://6pcolor.com/
|
| Disclosure: We have done color science, software and hardware
| consulting for 6P.
| nine_k wrote:
| If not under an NDA, what are they using to represent the
| super-bright reds and greens? Lasers? And, more
| interestingly, the super-greens and super-blues that are very
| dark and highly-intense?
|
| (I worked for a printing house and I know that some colors
| are outside RGB and outside CMYK, so they are printed as spot
| colors. There is a ton of Pantone colors you cannot mix, and
| must add from special one-color cans, like the Reflex Blue.
| Some customers want them badly.)
| aristus wrote:
| Maybe off topic, but I'd love to know more about those
| "practical" reasons for having two green bits in the Bayer
| system. I guess to your point, they needed four readings and
| might as well double up on the band humans have more cones to
| detect.
|
| But also I wonder how those kinds of decisions end up coloring
| so to speak AI. Training a model on image compression designed
| to fool the human eye is basically forcing it to reverse
| engineer the human eye.
| LeanderK wrote:
| I though the green in the bayer-filter was over-represented
| because the human eye is more sensitive to green compared to
| other colours?
| Syzygies wrote:
| Exactly. It's the best proxy for grayscale detail.
|
| One could have balanced RGB in a hexagonal grid. That's
| harder to build and slower to process.
|
| He would have considered a hex grid, but our rectilinear
| cognitive bias was pretty entrenched. Before this work, he
| programmed an entire image processing system in the "ed" PDP
| editor, manipulating character arrays. That experience
| influenced both the Bayer filter and Bayer dithering. And it
| taught me to look for simple ways to do things.
| KingLancelot wrote:
| [dead]
| nine_k wrote:
| "All models are wrong, but some are useful." One has to always
| remember about both of these properties.
| IIAOPSW wrote:
| I have a simple theory of colors. Look at how the color cells are
| distributed in the retina. Same pattern, but at slightly
| different scales (spatial frequencies). I speculate color is
| coded the same as spatial information. Or rather, the brain
| assumes that spatial frequencies coincident with the cell spacing
| are most probably because the object is that color, not because
| the object is weirdly striped as black and white in exactly the
| same pattern as the retina. But as far as data stream goes, the
| color and spatial information are the same thing.
|
| This theory comes entirely from observations on (and of people
| on) LSD. In particular, fine grain spatial information often
| drifts out of phase and manifests as a rainbow effect. Looking at
| an image of TV static its possible to see it as the black/white
| parts swirling or as color glitching outlines depending on how
| you choose to focus your eyes.
| Someone wrote:
| > I speculate color is coded
|
| https://en.wikipedia.org/wiki/Color:
|
| _"Color (American English) or colour (Commonwealth English) is
| the visual perception based on the electromagnetic spectrum."_
|
| = colors aren't coded; they are created in the brain. Outside
| it, all there is are light spectra.
|
| > Or rather, the brain assumes that spatial frequencies
| coincident with the cell spacing are most probably because the
| object is that color, not because the object is weirdly striped
| as black and white in exactly the same pattern as the retina.
|
| So, how do you explain that subjects do not change in colour
| when you move closer to them or further away, or when you
| divert your gaze (cone cell spacing is far from uniform across
| the retina)?
| vanattab wrote:
| They do actually. You have very poor short wavelength cone
| sensitivity in the fova precisely because of the low density
| of s cones
| MauranKilom wrote:
| > So, how do you explain that subjects do not change in
| colour when you move closer to them or further away, or when
| you divert your gaze (cone cell spacing is far from uniform
| across the retina)?
|
| To be clear, this is not a rejection of the theory, because
| your brain does a lot of magic to make color (or even object)
| perception "stick" as things move in and out of peripheral
| vision. See for example:
|
| https://en.wikipedia.org/wiki/Filling-in
|
| https://en.wikipedia.org/wiki/Lilac_chaser
|
| https://en.wikipedia.org/wiki/Color_constancy
|
| https://en.wikipedia.org/wiki/Memory_color_effect
| pavlov wrote:
| So you're saying the data stream to the brain is essentially an
| analog NTSC TV signal?
|
| Because that's how color was encoded: as high frequencies in
| the spatial scan. This was conveniently backwards compatible
| with analog black & white TV, at the expense of color accuracy
| (which is why the standard was sometimes called "Never Twice
| Same Color".)
| IIAOPSW wrote:
| Like NTSC/PAL but in a (possibly redundant) basis that is
| highly optimized by evolution for 3d objects projected down
| to the 2d retina. Not a rectilinear scanline per se but
| conceptually similar.
| jmole wrote:
| " Hering's original argument:
|
| Hering put forward two arguments. First, that mixtures of his
| opponent colors ('reddish green') are inconceivable.
|
| ...
|
| Second, Hering argued that unique hues are unique insofar as they
| describe all colors and cannot themselves be described."
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