RGBA stands for Red-Green-Blue-Alpha and specifies a color using four values which represent the amount of red, green, blue and alpha (opacity) in the color.
Questions tagged [rgba]
493 questions
235
votes
5 answers
Sass - Converting Hex to RGBa for background opacity
I have the following Sass mixin, which is a half complete modification of an RGBa example:
@mixin background-opacity($color, $opacity: .3) {
background: rgb(200, 54, 54); /* The Fallback */
background: rgba(200, 54, 54, $opacity);
}
I have…
![](../../users/profiles/1160747.webp)
Rick Donohoe
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218
votes
12 answers
CSS hexadecimal RGBA?
I know you can write ...
background-color: #ff0000;
... if you want something that is red.
And you can write ...
background-color: rgba(255, 0, 0, 0.5);
... if you want something red and translucent.
Is there any terse way of writing partially…
![](../../users/profiles/871202.webp)
Li Haoyi
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200
votes
7 answers
Convert RGB to RGBA over white
I have a hex color, e.g. #F4F8FB (or rgb(244, 248, 251)) that I want converted into an as-transparent-as-possible rgba color (when displayed over white). Make sense? I'm looking for an algorithm, or at least idea of an algorithm for how to do…
![](../../users/profiles/578895.webp)
Mark Kahn
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113
votes
7 answers
Convert RGBA PNG to RGB with PIL
I'm using PIL to convert a transparent PNG image uploaded with Django to a JPG file. The output looks broken.
Source file
Code
Image.open(object.logo.path).save('/tmp/output.jpg',…
![](../../users/profiles/284318.webp)
Danilo Bargen
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112
votes
15 answers
CSS background opacity with rgba not working in IE 8
I am using this CSS for background opacity of a
:
background: rgba(255, 255, 255, 0.3);
It’s working fine in Firefox, but not in IE 8. How do I make it work?
![](../../users/profiles/158455.webp)
Moon
- 17,794
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107
votes
15 answers
90
votes
5 answers
Sass/Compass - Convert Hex, RGB, or Named Color to RGBA
This may be Compass 101, but has anyone written a mixin which sets the alpha value of a color? Ideally, I would like the mixin to take any form of color definition, and apply transparency:
@include set-alpha( red, 0.5 ); //prints rgba(255,…
![](../../users/profiles/1081553.webp)
Pat Newell
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54
votes
5 answers
Overlay a background-image with an rgba background-color
I have a div with a background-image. I want to overlay the background-image with an rgba color (rgba(0,0,0,0.1)) when the user hovers the div.
I was wondering if there's a one-div solution (i.e. not with multiple divs, one for the image and one for…
user1544337
51
votes
8 answers
How to replicate PS multiply layer mode
Does anybody know of a good way to replicate Photoshop's multiply layer mode using either an image or CSS?
I'm working on a project that has thumbnails that get a color overlay when you hover over them, but the designer used a layer set to multiply…
![](../../users/profiles/1824709.webp)
Andrew Philpott
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51
votes
7 answers
CSS: lighten an element on hover
Assuming an element is at 100% saturation, opacity, etc... how can I have its background become slightly lighter when it is hovered?
The use case is that I'm allowing a user to hover over any element on a page. I don't want to go around determining…
![](../../users/profiles/1001938.webp)
Don P
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33
votes
4 answers
Convert RGBA to HEX
Given a css color value like:
rgba(0, 0, 0, 0.86)
How do I convert that to a RGB hex value that takes the alpha component into account, assuming a white background?
![](../../users/profiles/58962.webp)
Michael Böckling
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32
votes
5 answers
Color similarity/distance in RGBA color space
How to compute similarity between two colors in RGBA color space? (where the background color is unknown of course)
I need to remap an RGBA image to a palette of RGBA colors by finding the best palette entry for each pixel in the image*.
In the RGB…
![](../../users/profiles/27009.webp)
Kornel
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32
votes
3 answers
How to convert rgba to a transparency-adjusted-hex?
I'm wondering how to convert rgba into hex in a way that translates the visible rgba-color (including transparency) into a hex value.
Say I have this:
rgba(0,129,255,.4)
Which is sort of a "light blue"...
I would like to know if there is a way to…
![](../../users/profiles/536768.webp)
frequent
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25
votes
3 answers
CSS RGBA border / background alpha double
I'm working on a website that has a lot of transparency involved, and I thought I would try to build it entirely in RGBA and then do fallbacks for IE. I need a "facebox" style border effect, where the outer border is rounded and is less opaque than…
![](../../users/profiles/314989.webp)
stockli
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22
votes
2 answers
ValueError: Invalid RGBA argument: What is causing this error?
I am trying to create a 3D colored bar chart using ideas from: this stackoverflow post.
First I create a 3D bar chart with the following code:
import numpy as np
import matplotlib.colors as colors
import matplotlib.cm as cm
import matplotlib.pyplot…
![](../../users/profiles/4949315.webp)
Inspired_Blue
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