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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.

468 questions
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good 3D explosion & particles effect using OpenGL (JOGL)?

I've been wanting to write it for some time now... as a project for the university, I've written (with a friend) a game that needed good explosions & particles effects. we've encountered some problems, which we solved quite elegantly (I think), and…
gilad hoch
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Calculate resulting RGB from 2 colors, one is transparent

I'm looking for a formula to convert them. I know to convert a general transparency it is alpha * new + ( 1 - alpha ) * old I have: Color A : RGB( 85, 113, 135 ) Color B : RGB( 43, 169, 225 ) Color A has 90% opacity and is laid on top of Color B,…
Kerry Jones
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calculate RGB equivalent of base colors with alpha of 0.5 over white background in matplotlib

I would like to be able to replicate the look of a primary color ('r','g' or 'b') in matplotlib with an alpha of 0.5 over a white background, while keeping the alpha at 1. Here is an example below, where through manual experimentation I've found the…
themachinist
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Set the background color for a PNG with transparency

I am loading PNG images that have a transparency plane. When converted to grayscale, the transparent areas in the image appear as black, which seems to be the default background. I need them to be white instead. What can I do ? [This is not the…
user1196549
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android native video playback with alpha channel

Does android support alpha channel in any of its native supported video formats, or does anybody has an idea if it is in the pipeline? Might be possible in h.264 in android in 3.0 ?
ziggestardust
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How to push view controller with transparency mode?

I am trying to push a view controller with transparency mode. This is my code: SearchViewController * searchViewController= [self.storyboard instantiateViewControllerWithIdentifier:@"SearchViewController"]; searchViewController.view.backgroundColor…
Kishore Kumar
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Issue in checking UIImage have alpha (Transparent) color or not

I'm checking that image have transparent area (alpha) or not. Bashed on that I have to change the color of UIImage I have implement the below method to check the image have alpha or not. - (BOOL) checkAlpha : (UIImage*) image { for(int x = 0;…
Hitarth
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Splitting webm video to png with transparency

I need to split a webm encoded video into png frames, without losing transparency. I use the following ffmpeg command: ffmpeg -i dancer1.webm -pix_fmt rgba frames/%04d.png This produces a directory of pngs, but why is each output frame is missing…
Stephen Emslie
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Implementing Cursor in Java with some Transparency

I have a 35x40 px. png image I want to use as a custom cursor in a Swing application. The image has a glow so contains alpha transparency values. Problem is when I attempt to use the conventional method of using the Toolkit to generate the custom…
Sammy Guergachi
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How to set alpha value for drawable in a StateListDrawable?

I want to change a drawable's alpha value when it is pressed. So I create two drawables and put them in a StateListDrawable and set the alpha value for the pressed state. But it just doesn't work. StateListDrawable content = new…
Aniki
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Video with transparency, how to display alpha channel of webm files correctly on every device; VP9 or VP8 encoding?

About how to get a transparent background with a webm video via alpha channel, here is one person that says you should encode with VP8 and not VP9. WebM Alpha only displayed in Chrome? And here is another person who says it's the opposite thing,…
HolyResistance
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Drawing a dynamic transparent image over another Image using SWT Graphics

I'm attempting to draw a transparent mask of combined shapes over the top of an already in place image. I have provided an example of the techniques I'm trying via the dialog code included in this post. Here's a screenshot of what it produces.…
Link19
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Matplotlib: how to have a transparent box plot face while a non-transparent line edge?

I'm building a function to draw custom box plots. I'd like the face of the boxes to be plain with slight transparency and I'd like a thin solid (non-transparent) line around each box face. I've been attempting this by setting the parameters of…
p-robot
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turning a div into transparent to see through two containers

I have following markup
and i have applied a fixed background to body element and white background applied to class holder body { background: url(image.png); …
It worked yesterday.
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PNG with transparency from Photoshop to Flash: how to make .swf display exactly what .psd does?

I have two layers in Photoshop: 1 -- a texture, 2 -- a semi-transparent image that overlaps texture. The combination of the two looks nice in Photoshop. I export them separately from Photoshop saving them as 24 bit PNG with transparency and colors…
Michael Antipin
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