sRGB CVD Simulation Web App

Color Vision Deficiency Simulator — sRGB

MyndexCVD Sim—sRGB Version

This is a different simulator of Color Vision Deficiency (CVD), this is specifically related to the perception of metameric displays, i.e. sRGB tristimulus monitors. This sim was created as part of our research into vision and accessibility. It is designed to be a perceptually accurate model of how CVD sees an sRGB monitor.

The main (Brettel based) simulator is here.

Click To Show Description

This simulation model is based on how various forms of CVD perceive each of the independent tristimulus primaries of an sRGB monitor in terms of their luminance function, and then combining certain primaries using coefficients that are modified relative to the type of CVD being modeled.

For instance, protanopia sees the RED sRGB primary as a little less than half the luminance of a normal observer. Thus this protanopia simulator reduces the standard 21% red coefficient to 9.5%, and then combines & scales the red and green channels.

Cutting the red channel luminance in half results in a perceptual lightness reduction of only 31% or often much less depending on the other colors involved. In the case of max red at #FF0000, the equivalent is #B20000 which results in the perceived L* difference of 16, from L* 53.2 to 36.9 (31% lower) however #FFFFFF to #B2FFFF is only an L* difference of 5 (just 5% perceptually darker for FFF white).

This deuteranopia sim simply combines the red and green channels (the mixing is done after converting to linear, applying the standard coefficients, and some minor scale adjustments).

The Tritanopia simulator (blue deficient) essentially turns off the blue channel. To mimic the perceptual "feel" for normal observers, the red and green channels are combined, scaled, and sent to blue to balance the white point.

The last square is simply sRGB converted to Y (luminance, as in CIEXYZ). The sRGB is linearized, then the standard coefficients are applied, summed, gamma re-applied, and then sent to each of the R´G´B´ color channels. Note also that this simulator is using the true sRGB transfer curve instead of simple gamma for all of the simulations, and the sRGB colorspace is assumed for all simulations.

There are several images hosted here to choose from, or you can use your own image source. To use with your own images, just upload an sRGB JPEG or PNG image using the form below. sRGB colorspace is assumed — other color profiles will cause unpredictable and inaccurate results. Image size is limited to about 615px X 900px. Larger images will be resized and/or cropped as needed. Processing takes place locally on your machine so speed is dependent on your computer/device as well as image size.

And to be clear — this is specifically how CVD may see stimuli on an sRGB monitor. For a simulation of how CVD sees the world in general, Please see our main simulator, which is based on the Brettel studies.

Normal Trichromatic Vision

Orange Flower Button
Pink Rose Button
Little Flowers Button
Pink & Purple Button
Red Flower Button
A Daisy Button
Busy Bee Button
Mae Orange Button
Kristen Sky Button
Mae Pink Button
Rapper Des Button
Grettle Red Button
Temple Priest Button
Bar BlueMoon Button
Eiffel Fireworks Button
Bar Booths Button
Bar Bottles Button
Bar Snifter Button
Process Your Own!     Current:   Preset
Privacy Note: processing your images on this page does not upload them to any server. All processing happens locally on your machine in this webapp — we'll never see it.

sRGB Protanopia

Missing L Cones (Red Cones)

sRGB Deuteranopia

Missing M Cones (Green Cones)

sRGB Tritanopia

Missing S Cones (Blue Cones)

sRGB Luminance

sRGB reduced to Y (Monochromatic)



These Simulation Models are based on:

    ➢ SIMULATIONS: Protanopia & Deuteranopia, & Tritanopia
Andrew Somers
sRGB Displays and Color Vision Deficiency.
(Unpublished, Active Research)

    ➢ SIMULATIONS: sRGB Luminance to Grayscale
Based on sRGB Standard IEC 61966-2-1:1999
Wikipedia sRGB page

Related Resources:

Brettel, Viénot F, Mollon JD (1997)
Computerized simulation of color appearance for dichromats.
Vol. 14, No. 10/October 1997/J. Opt. Soc. Am. A

Viénot, F., Brettel, H. & Mollon, J. D. (1999)
Digital video colourmaps for checking the legibility of displays by dichromats.
Color Research & Application, 24, 243-252.

H Fukuda1, S Hara, K Asakawa1, H Ishikawa1, M Noshiro1, M Katuya (2015)
Computer Simulation of Color Confusion for Dichromats in Video Device Gamut under Proportionality Law
IPSJ Transactions on Computer Vision and Applications Vol.7 41–49 (May 2015)

G. Machado, M. Oliveira, and L. Fernandes (2006)
A Physiologically-based Model for Simulation of Color Vision Deficiency
IEEE Transactions on Visualization and Computer Graphics ( Volume: 15 , Issue: 6 , Nov.-Dec. 2009 )

V Smith, J Pokorny (1972)
Spectral Sensitivity of Color-Blind Observers and the Cone Photopigments
Yision Res. Vol. 12, pp. 2059-2071. PergamonPress 1972. Printed in Great Britain.

Deane B. Judd (1949)
Response Functions for Types of Vision According to the Muller Theory
Part of Journal of Research of the National Bureau of Standards, Volume 42, January 1949

Interesting Concepts in Improving Accessibility:

David R. Flatla (2011)
Accessibility for Individuals with Color Vision Deficiency
Doctoral Symposium UIST’11, October 16–19, 2011, Santa Barbara, CA, US

Huei-Yung Lin, Li-Qi Chen, & Min-Liang Wang (2019)
Improving Discrimination in Color Vision Deficiency by Image Re-Coloring
Sensors (Basel). 2019 May; 19(10): 2250.

Jia-Bin Huang, Sih-Ying Wu, and Chu-Song Chen (??)
Enhancing Color Representation for the Color Vision Impaired

Gretchen M. Culp (2016)
Increasing Accessibility for Map Readers with Acquired and Inherited Color Vision Deficiencies: A Re-Coloring Algorithm for Maps
CUNY Academic Works.

Huang, Tseng, Wu, Wang (2007)
Information Preserving Color Transformation for Protanopia and Deuteranopia
October 2007IEEE Signal Processing Letters 14(10):711 - 714 DOI: 10.1109/LSP.2007.898333

M. Madalena, G. Ribeiro, Abel J.P. Gomes (2019)
Contour Enhancement Algorithm for Improving Visual Perception of Deutan and Protan Dichromats
International Journal of Interactive Multimedia and Artificial Intelligence, Vol. 5, No 5

Tools and Other Apps:


Also check out ColorOracle, a useful free tool that installs in your menu bar. Good for designers that want a "quick check" of what they are working on. A click or hot key sets then entire screen to a simulation.

sRGB gamma target. Adjust the monitor so that the square appears uniform (i.e. not pyramids). Note also it is important that the image be at 100% and not scaled - make sure your browser says "actual size". If the square "looks like a pyramid" that indicates your monitor is not calibrated to the sRGB transfer curve (sometimes called gamma).