Questions tagged [color]
Questions about the visual perceptual property deriving from the spectrum of light, usually expressed numerically according to a color model.
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Determine paint color from a photo
I ran into this problem while trying to find the paint color of the doors in my house: is it in principe possible to automatically determine the paint color from a photo?
Different types of colour ...
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Extracting the green-screen region borders
Given a png image with an unknown number of green colored (rgba=0, 65535, 0, 65535) regions
1- How can I find and put the border points of only the separate green boxes to an array like:
...
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What are the main concepts behind building the plasma effect with GSLS?
By the plasma effect I mean an animation that looks like this:
I have seen some codes, like these
https://www.shadertoy.com/view/Xst3zN
https://www.shadertoy.com/view/4tdGWX
and messed with the code ...
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Raytracer help - Background color writing over some colors?
I'm implementing Peter Shirley's "Raytracer in a Weekend: The next week" and I'm having some trouble with rendering a scene with a light. I'm not sure if the issue is the background color or ...
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How could I remove this colour interpolation artefact across a quad?
I've been reading up on a vulkan tutorial online, here: https://vulkan-tutorial.com. This question should apply to any 3D rendering API however.
In this lesson https://vulkan-tutorial.com/...
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How to get "Equal" (saturation, brightness) Red and Green Colours in a Web-based Application?
I am looking for a red and a green hue that are equally discernable against a gray background on any PC monitor, using HTML/CSS-based application. There are many possible solutions to balance these ...
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Alpha part of color class or shape class
I am designing a 2D drawing library (it is its very early stages) and I was wondering what to do with Alpha (transparency).
I have two trains of thought:
A. Implement Alpha in the Color class ...
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What image formats support indexed color palettes with more than 256 colors?
I've been reading up on images with indexed color, and while most indexed image formats are limited to 256 colors, there are apparently image formats that support larger palettes.
According to ...
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Path tracing - Better images without Gamma correction?
So I read about tonemapping and Gamma Correction recently and have implemented it in my path tracer.
For the time being I'm using Reinhard tonemapping operator as described in his paper
$L_d = L_w *...
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What causes this color shift?
Below are the original image and a JPEG encoded/decoded image. To my untrained eyes, cyan becomes yellow, yellow becomes magenta, and magenta becomes cyan. Obviously there's a problem with the ...
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Why does this edge detect show different results for the same color combinations?
I'm researching highlighting accessible color contrast via filter operations. I have a test screenshot of SRGB hex values compared with WCAG's official contrast algorithm:
I converted it to its ...
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How do I add two color values containing alpha?
I started out writing my Color class as just containing R, G, B triplets. Adding colors in this situation turns out to be fairly simple.
...
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Does CMYK values provide more colors than RGB?
We know that in the RGB system we have three primary colors and each of them has a value from $0$ to $255$ (or $256$ values in total). So all possible colors are $256^{3}=16777216$.
But in the CMYK ...
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Animated rainbow distortion wave effect
https://foundation.app/mg/20210227-3lau-makes-history-1790
The link above shows a video animation that has a rainbow wave distortion effect applied to it, that ripples across the video. how, and in ...
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correct rgb or cmyk code from some proportion of cyan, magenta and yellow
I am trying to find a way to go from some proportion of cyan, magenta and yellow where:
cyan: 33 % + magenta : 33% + yellow : 33% = 100% black
so each is represented as a percentage of the sum ...
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What is the name of this moving color pixels effect, for animating a painting?
https://superrare.co/artwork-v2/spring-22267
The artwork in the link seems to be based on a painting of a woman, but effects have been added that assign a pixel to each block of the painting that ...
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What is the relation between colour spaces and what is actually displayed on our screens?
I am not entirely sure that this is the right stack exchange, but I couldn't find any other suitable one - please redirect me if necessary.
There exists mathematically defined colour spaces which help ...
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Is there a way to automatically optimize imags based on predefined marker on image?
Color correction is tricky. It's always a lot of work to make everything look same.
I have multiple products (clothing) to take a picture of. One is 100% red, other 100% Orange. Some are multicolor ...
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Why are the HSL and HSV color models not considered "perceptually uniform"?
The HSL/HSV color spaces are not considered "perceptually uniform" despsite being widely used. Is there a detailed reason for this?
user19242
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How to visualize color synthesis in HSL diagram
before considering the HSL color space, let's consider the CIE chromaticity diagram to understand what I'm looking for:
Unless I am mistaken, I read it that way:
Given two points A, B, any color in ...
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Why does my Dell laptop monitor give this weird color banding?
I've noticed some very obvious color banding on the screen of my Dell Precision 7750 laptop while watching video (same in every video program; VLC, built-in Windows video player, etc.) Not only does ...
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Converting color to equivalent with opacity
Assume a color X with alpha 1 and RGB 255,230,210.
How can i find another color with alpha A ( or an array of colors ) that blended with a background of color Y ( e.g 255,255,255 ) would produce the ...
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Quick 2-color quantization for small images
So I have a small (8x8 pixel) image in 24-bit color. I want to be able to (quickly) generate a color-quantized version of the image that only has two colors.
One naive approach is to cluster a luma ...
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What remedies are there for percieved color artifacts due to pixel geometry?
I have a white line on black background. Because of the pixel geometry the line does not look really white; one edge looks red-isch, the other blue-isch. Other fore- and background yield other ...
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Normal blend mode math
I have one question.
How to calculate source color after blending operation.
For example. I have
1 - Background color (r-115, g-94, b-67, a-1)
2 - Foreground color above background color, which ...
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With a light source at (0,2,0) and unit cube (from [-1,1]) using a given shading formula, how is the r,g,b for each surface calculated?
The above problem is from a past Computer Graphics exam.
I am particularly confused about the explanation given, firstly for the top and bottom planes (since the direction of normal for top plane ...
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What is the color space of Luminosity blend mode and other three blend modes that photoshop use , HSB HSL or LCH
Here is what I have tried:
I create a base layer and a blend layer and I choose Luminosity blend mode, so the result suppose to have the hue and Saturation of the blend layer and the Luminosity of the ...
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What happens when we select lower resolutions on a high-resolution monitor?
I have a monitor with a resolution of 1360x768 (16:9), When I set the resolution to 1280x768 (5:3), 1024x768 (4:3), 800x600 (4:3), even 1920x1080 (16:9) it completely covers the screen and the monitor ...
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Aligning (matching) colors (white balance, brightness) of two scenes based on reference object
What I am trying to do is to become able to compare with reasonable accuracy two real world fabric/textures (colorwise speaking) at two distinct locations. I can't move them into single place to ...
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Sub pixel rendered white text on black background changes color when resized to a very small size
download: https://upload.wikimedia.org/wikipedia/commons/5/57/Subpixel-rendering-RGB.png
The above picture is an example for sub pixel rendering. I tried resizing the image to very small size in ...
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Converting ACES ap0 color space into srgb?
I'd like to know the correct when of converting ACES AP0 color space into sRGB. Let's say artists decide to pick colors outside of sRGB in AP0, will ACES handle this situation correctly, meaning no ...
