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Questions tagged [alpha-transparency]

The alpha transparency of an image defines how transparent the pixels of this image are. Typically, each pixel has an alpha value between 0 (fully transparent) and 255 (fully opaque).

Alpha transparency is an attribute of pixels within an image (or image layer) which determines how transparent the pixel is, by blending the pixel color with the color of the pixel in the layer beneath it. most image editing software allow to edit a layer or image alpha transparency. The alpha value is saved in addition to the RGB value of the pixel. Ranges of transparency may change according to the software setup.

Alpha Transparency as part of Alpha Compositing.

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Alpha transparency not uniform when plotting a shapefile with Geopandas

When plotting a shapefile with Geopandas, I need to make the features transparent. When applying an alpha parameter, some of the features become less transparent than others. fig = plt.figure(figsize = (8.5,11)) ax…
etotheipi
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Want to make text div transparent on a parallax area

I am trying to make a text div transparent on a parallax area. Here is my code:
Jim
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openGL Transparent pixels unexpectedly White

I noticed a big problem in my openGL texture rendering: Assumedly transparent pixels are rendered as solid white. According to most solutions to similar issues discussed on StackOverflow, I need to set glBlend / the proper functions, but I have…
synchronizer
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How do I introduce transparent regions into Numpy image arrays?

The input images are loaded: target_img = spi.imread(target_img, mode="RGB").astype(float)/256 source_img = spi.imread(source_img, mode="RGB").astype(float)/256 target_mask = spi.imread(target_mask, mode="RGB").astype(float) source_mask =…
ProGamerGov
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Delphi FMX TImage manual alpha transparency mapping failure

I am trying to create a TImage with alpha transparency using code. In this example, an anti-aliased circle. I create an 8bit opacity map for the circle and then apply it to the TImage's TBitmap using this piece of code: type TOpacityMap =…
bLight
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Java Swing: Ghost text showing up when updating text on a JTextArea with partially transparent background

So here's the deal: I've got a JPanel and a JTextArea inside that one. The JPanel has a background color which has an alpha value of 200, ie. you can paritally see the background image through the JPanel. Ain't that called partial transparency?…
an55i
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Use native HBitmap in C# while preserving alpha channel/transparency

Let's say I get a HBITMAP object/handle from a native Windows function. I can convert it to a managed bitmap using Bitmap.FromHbitmap(nativeHBitmap), but if the native image has transparency information (alpha channel), it is lost by this…
TechAurelian
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Rendering transparent texture onto glTexture

I've been working in opengl for a while relatively smoothly, but recently I've noticed that when I render a primitive with a transparent texture onto my fbo texture (custom frame buffer) it makes the fbo texture transparent at the pixels the…
HelloWorldCpp
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Alpha component on UIBezierPath Fill

I have a view defined like this : class TriangleView: UIView { override func drawRect(rect: CGRect) { // Get Height and Width let layerHeight = self.layer.frame.height let layerWidth = self.layer.frame.width // Create Path …
Alk
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Delphi unexpectedly draws in Image's alpha channel

I have a TImage into which I loaded a PNG with transparency. David hinted me how to give it a bitmap to draw on: var Png: TPngImage; Bmp: TBitmap; begin Png := TPngImage.Create; Bmp := TBitmap.Create; try …
Joris Groosman
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internet explorer: semi-transparent images

I have the two images below. They are the same image, with one having a slight glow effect on the text. They are setup as below: withe the original image being the background for the div, and the 'glow' image being the…
Hailwood
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inconsistent behavior with "undocumented Matlab" figure handles

I read the blog post on assigning transparency to plot markers. I tried the code on a simple example and all was well. Then I tried a tight loop, plotting a single point at a time (doing this to assign a different color to each point in the graph),…
Carl Witthoft
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Fill transparency with geom_violin

How can increase the alpha of the fill of violin plots but not the alpha of the boundary line? Changing alpha as an argument to geom_violin() results in both the fill and line changing.
saladi
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Hiding only the part of an element that scrolls behind a fixed transparent nav bar

I have searched a lot for an answer to this and have found lots of similar issues but haven't managed to find a solution that works for me. I'm probably just missing something very obvious. I have a fixed transparent nav bar that is 40px from the…
charliesd
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three.js SoftwareRenderer - transparent background

I'm playing around with one of the three.js examples http://threejs.org/examples/#software_geometry_earth How do I make the background transparent? The following does not work for the SoftwareRenderer (but it does work for the WebGLRenderer, but I…
Agent Zebra
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