My Color-Blindness Simulator

[lpetrich]

Some time ago, I had created a color-blindness simulator (http://homepage.mac.com/lpetrich/ColorBlindnessSim/ColorBlindnessSim.html) -- a web-browser applet and a standalone program that simulates various sorts of color-vision deficiency. I'm now introducing it here.

http://homepage.mac.com/lpetrich/ColorBlindnessSim/Demo/CBSim.png
Normal
http://homepage.mac.com/lpetrich/ColorBlindnessSim/Demo/CBSim_1.png http://homepage.mac.com/lpetrich/ColorBlindnessSim/Demo/CBSim_2.png http://homepage.mac.com/lpetrich/ColorBlindnessSim/Demo/CBSim_3.png
Protanopia, Deuteranopia, Tritanopia
No-Red, No-Green, No-Blue
http://homepage.mac.com/lpetrich/ColorBlindnessSim/Demo/CBSim_Dog.png
Dog Vision

The latter one I have added to remedy a deficiency of many color-blindness simulators. With its help, you can see the world colored in the way that dogs see it.

It accepts input images from files in your computer, from over the Internet, and even from screenshots that it can take.

Its "Extras" button makes a dialog box for these options:

Partial color blindness
Gamma correction (1 to 2.2)
Other simulation algorithms
Handling of off-edge colors


Its algorithm is not original with me, of course; it is based on several others' work, notably

Computerized simulation of color appearance for dichromats. (http://www.ncbi.nlm.nih.gov/pubmed/9316278?dopt=Abstract)
J Opt Soc Am A Opt Image Sci Vis. 1997 Oct;14(10):2647-55.
Brettel H, Viénot F, Mollon JD.

What do colour-blind people see? (http://www.ncbi.nlm.nih.gov/pubmed/7603561?dopt=Abstract)
Nature. 1995 Jul 13;376(6536):127-8.
Viénot F, Brettel H, Ott L, Ben M'Barek A, Mollon JD.

You can find other online color-blindness simulators at Vischeck (http://vischeck.com/), Sim Daltonism (http://michelf.com/projects/sim-daltonism/) for OSX, HTML Writers' Guild Color Laboratory (http://colorlab.wickline.org/colorblind/colorlab/), etc.

The image editor GIMP (http://www.gimp.org/) also has this capability:
(image menubar) > View > Display Filters...

None of them do dog vision, however.

When Firefox 3.5 comes out, it may have in it Applying SVG Effects to HTML Content (http://weblogs.mozillazine.org/roc/archives/2008/06/applying_svg_ef.html), meaning that it will be possible to create a webpage that can load other webpages in it and filter their rendered appearance.

[Daynna]

Very cool Ipetrich! My husband is color-blind, though not sure which kind. It only becomes apparent when discussing clothing, or playing a game with colors (like Hexic).

[lpetrich]

Daynna, you may be able to tell by finding out which colors he tends to confuse. Different sorts of color blindness involve confusing different sets of colors, as you can see from my demo pictures.

[LoneWolf]

I have some sort of red green color blindness. I always fail those numbers hidden in the dots tests that the military gives me. It is weird because when I look at your avatar, lpetrich, it certainly looks green to me and I do just fine at traffic lights. It is just those damn color tests I can't do.

[lpetrich]

The Ishihara-plates tests? Yes, some of them can be difficult even for me, with my full-scale color vision. But their difficulty can be useful for diagnosing partial cases.

And how do the various hues in my demo image compare? How do red (12 o'clock) and green (4 o'clock) compare? Do they look like different brightnesses of the same hue? Or do they look like slightly different hues?

When I mean slightly different, I mean that they look much more alike than either looks like blue (8 o'clock).

[LoneWolf]

12 o'clock and 4'olock do look much more alike than either looks like blue (8 o'clock), especially in the 2nd one on row number two (deuteranopia)

In the dog vision one you say there is no blue. I see blue from about 6 o'clock to 11 o'clock. Am I misunderstanding the description?

[lpetrich]

12 o'clock and 4'olock do look much more alike than either looks like blue (8 o'clock), especially in the 2nd one on row number two (deuteranopia)
All but the first one already have simulations of various sorts of color blindness, so it's the first one that's the most useful for testing one's vision.

And your report agrees with that diagnosis -- you have partial red-green color blindness.

In the dog vision one you say there is no blue. I see blue from about 6 o'clock to 11 o'clock. Am I misunderstanding the description?
The "No-Red, No-Green, No-Blue" text is the second line in the caption of the images above it. Is that what you are concerned about?

In any case, you are correct about the dog-vision one looking blue from over that region.

[LoneWolf]

If all of a sudden I could see with normal color vision I wonder how different the world would look.

[BioBeing]

I have slight red green colour blindness. I can see red and green in the first image, and don't normally have issues, but in a presentation at work the other day, I could not make out the red text on someone's slides (a gray background, IIRC). I fail those find-the-number tests too.

[Alethias]

The five images in your opening post all look distinctly different to me. That seems odd to me, since I have a form of color-blindness where I have a difficulty distinguishing between certain specific pastels. I don't know for sure, but I'm wondering if your color-blindness simulator would seem either a little off or a lot off to many color-blind people, since it appears to me that it doesn't (or maybe I don't understand what you are doing here) distinguish between the fine variations from one color-blind person to the next.

My red-green color-blindness makes many tans and light-greens and light grays looks almost identical. But none of your pictures confuse my color vision at all.

And so it goes.

[LoneWolf]

My red-green color-blindness makes many tans and light-greens and light grays looks almost identical. But none of your pictures confuse my color vision at all.

Ahh, but how do you know? :)

People with normal vision may be seeing a wider spectrum of colors than you and I are.

[BWE]

I can match any color within a computer's tolerances by eye using ink or paint given the right colors to start with, yellow, rhodamine, magenta, navy, cyan, and black. (or the paint equivalents.

Seriously, as good, sometimes better than a computer paint mixing deal. I can look at the paints and tell you whether they will make a certain color.

I don't need a formula guide to mix a pantone color.

[lpetrich]

My red-green color-blindness makes many tans and light-greens and light grays looks almost identical. But none of your pictures confuse my color vision at all.
It looks like you have what Lone Wolf has, which is protanomaly or deuteranomaly -- deficient function of the red or green cones. They function enough to distinguish high-saturation colors, but not low-saturation ones.

[dancer_rnb]

:popcorn:

Enjoying this thread.

[Alethias]

My red-green color-blindness makes many tans and light-greens and light grays looks almost identical. But none of your pictures confuse my color vision at all.
It looks like you have what Lone Wolf has, which is protanomaly or deuteranomaly -- deficient function of the red or green cones. They function enough to distinguish high-saturation colors, but not low-saturation ones.Hmmm. that's a fitting description. Thanks. And it's not all low-saturation colors, just those in a certain range.

Talking about it in these terms casts it in a new light.

[Barefoot Bree]

Silly related question: what color ball would show up best on green grass for dogs? They can't find the green one I throw sometimes after it stops moving.

My choices for this particular ball, which they love chasing indoors (it's a rubber one with holes all over, kind of a huge holey swiss cheese effect, that their little mouths can easily grab and carry) are brick red, dark blue, and this grass green. Since dogs are red-blind, would the blue stand out best? Or would that red actually turn into something they can see well against the grass?

No, I don't have enough money to buy them all and experiment, otherwise I would.

[Oolon Colluphid]

If all of a sudden I could see with normal color vision I wonder how different the world would look.
Amazing, I imagine, like suddenly being able to see infrared maybe.

I have anosmia (no sense of smell), and the best way I can think to describe it to my daughter is to say that I taste in greyscale. I imagine that's the sort of difference you'd experience -- the visual version of getting your sense of smell back after a cold.

[Oolon Colluphid]

Silly related question: what color ball would show up best on green grass for dogs? They can't find the green one I throw sometimes after it stops moving.

My choices for this particular ball, which they love chasing indoors (it's a rubber one with holes all over, kind of a huge holey swiss cheese effect, that their little mouths can easily grab and carry) are brick red, dark blue, and this grass green. Since dogs are red-blind, would the blue stand out best? Or would that red actually turn into something they can see well against the grass?
Blues or purples -- that is, something at the opposite end of the spectrum from the green-yellow-red end that all looks the same to them.

Color Blindness in Dogs (http://www.dog-health-guide.org/colorblindnessindog.html)

http://www.dog-health-guide.org/images/dogvis.jpg

But apparently the best colour for a dog ball is a nicely contrasting pattern, something like purple on white, so it'll stand out on any background.

[Barefoot Bree]

Blue it is. Thanks, Oolon!

I've never heard of anyone without a sense of smell before. Do you compensate for it in any way, or does it not really affect you?

[Oolon Colluphid]

Blue it is. Thanks, Oolon!

I've never heard of anyone without a sense of smell before. Do you compensate for it in any way, or does it not really affect you?
This pdf (http://www.medicalpost.com/patientcare/pdf/jun06/patientcare_pd_jun06.pdf) has some interesting stuff about anosmia. As best I can guess, I got it in the flu epidemic of winter '68, when I was two -- my Mum always claimed I had been able to smell before that, but I have no memory of doing so.

I've no idea if I compensate. I suspect that my sense of taste is much better than other people's, but haven't ever bothered to investigate -- I'm not sure how, because the comparison would have to be with someone temporarily unable to smell too (so it'd be a taste-only comparison)... and everyone I've spoken to says that they can't taste 'anything' when their smell goes, so I'm not sure how accurate their perceptions would be.

I do tend to go a lot on texture; though again I've not checked, I think I'd have trouble telling bland things like plain chicken and white fish apart if they were blended up (or maybe they're not that bland, and it's just me!).

As far as affecting me... it doesn't, day-to-day. I can cook quite well. The main problems have been with things like if the cooker gas is on but not lit and I don't notice; the time I burned our wok black, and didn't realise till I started choking on the smoke... when a stink bomb was let off in a class at school, and I just sat there while everyone else ran out (and hence I got the blame). And I -- quite happily, may as well turn it to my wife's advantage :D -- copped more than my share of nappy duty when our daughter was a baby.

[BigEvil]

If all of a sudden I could see with normal color vision I wonder how different the world would look.

I am color blind and occasionally wonder the same thing. My color blindness doesn't cause any big problems but occasionally a few frustrations. At work, we are allowed to use blue ink on forms but not purple ink, I can't tell the difference and sometimes use purple ink.

[Nohweh]

Hey guys, check out my total blindness simulator. I would like to reveal the algorithms, but they are currently the subject of litigation. Sorry.

http://shadowshift.files.wordpress.com/2009/01/black_screen.jpg

[Oolon Colluphid]

Hey guys, check out my total blindness simulator. I would like to reveal the algorithms, but they are currently the subject of litigation. Sorry.
Doesn't work.

Not having been blind, I don't know for sure, but I suspect that looking at an absence of light is not the same as lacking sensory input.

:p

[Nohweh]

Well, it is only a simulator. ;)

[lpetrich]

I am happy to announce my updated version of my color-blindness simulators (http://homepage.mac.com/lpetrich/ColorBlindnessSim/ColorBlindnessSim.html). I have now written a version that works on webpages (http://homepage.mac.com/lpetrich/ColorBlindnessSim/WebpageCBSim.xhtml). You enter a webpage's URL, and you then select what kind of color blindness to simulate. You can even go to a link in that page, and the simulation will be done on the linked page as it loads.

However, you will need Firefox 3.5 or some other browser with similar capabilities, one capable of using SVG filters on HTML objects, as described in Applying SVG effects to HTML content (https://developer.mozilla.org/en/Applying_SVG_effects_to_HTML_content) at Mozilla's developer center.

[lpetrich]

I've updated my Color-Blindness Simulators (http://homepage.mac.com/lpetrich/ColorBlindnessSim/ColorBlindnessSim.html) to show more vision information.

They can now show the brightness information in an image:

http://homepage.mac.com/lpetrich/ColorBlindnessSim/Demo/CBSim_Gray.png

So if you could see no hue information, this is what you will see.

I've also tried to estimate what each kind of cone "sees", and they can now show these estimates:

http://homepage.mac.com/lpetrich/ColorBlindnessSim/Demo/CBSim_G1.png http://homepage.mac.com/lpetrich/ColorBlindnessSim/Demo/CBSim_G2.png http://homepage.mac.com/lpetrich/ColorBlindnessSim/Demo/CBSim_G3.png

Red-Only (L), Green-Only (M), Blue-Only (S)

[muidiri]

I have some sort of red green color blindness. I always fail those numbers hidden in the dots tests that the military gives me. It is weird because when I look at your avatar, lpetrich, it certainly looks green to me and I do just fine at traffic lights. It is just those damn color tests I can't do.

My dad's red-green defficient. We talked about this some, and he said a lot of it for him seems to be that his brain "knows" what color name goes with the items in that context.

You've learned that frogs are generally green - so your brain will automatically interpret the frog in Loren's avatar as a green one.

I'm curious - do you see these two frogs as the same or different?
http://www.walljungle.com/products_pictures/red%20poison%20dart_frog%20normal.jpg
http://www.calacademy.org/science_now/wild_lives/images/green_and_black_poison-dart_frog.jpg

For the most part, my dad has no problem functioning in real life - his learning compensates for the deficiency quite well. But when it comes to the dots... well, there's no learned reference for which of the dots should be which color.

sometimes it makes for good family stories though. My grandmother's house was green when she died and left it to my dad. He found a five-gallon bucket of house paint in the shed, and decided to do some touch ups. Apparently someone had intended to paint the house coral at some point and hadn't gotten around to it. To Dad, it looked the same as the green on the house. So for a while, he had a green house with random pink splotches :p. After a good laugh, his buddies clued him in.

[Zygote]

A similar thing happened to my red-green colorblind grandfather. He had an big oldsmobile that, due to its size and silvery rose hue, had been christened the Titty Pink Dragon. When parking by braille one day, he scored a long mark down the side.

Always one to take matters into his own hands, he refused help at the auto parts store and picked out his own touch up paint. Until the day he died, that car had a mint green stripe running most of the way down the right hand side.