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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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Delphi 2006: Run-time assignment of PNG to TImage loses alpha transparency

Delphi 2006's TImage doesn't quite support PNGs. In order to have images with alpha transparency on my forms I have to load them at run-time. I can load them at design time but they don't survive, I think because PNGs are not saved in the DFM…
rossmcm
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Apply gradient mask on image that already has transparency with ImageMagick?

I've got a PNG image with transparency: original.png Now I want to use ImageMagick to apply a diagonal gradient to its alpha channel. I mean so that its opacity remains in the top left corner, and gradually fades out to completely transparent in…
RocketNuts
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PNG with alpha-transparency to SVG with potrace

I'm using potrace to convert a png file to svg. The png is black on transparent background with alpha-transparency levels. I would like to report them in the svg output. Is it possible ? Potrace skips the alpha-transparency and turns it to…
Lolo
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unable to transparent pixels of a bitmap image

I am working with bitmap images whose transparent parts are colored in magenta (in some languages it is possible to set a color as transparent). I try to transparent pixels which are in magenta in the original bitmap image. I load the bitmap from…
Behy
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Tkinter see through window not affected by mouse clicks

I am currently controlling a game with python by sending mouse and keystroke commands. What I am looking to do is have a transparent Tkinter window lay overtop of the game to provide some information such as mouse location and pixel color. I am…
Alec Mitchell
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delphi convert gif to png with transparency

I am trying to convert a gif to png, that's easy, but the problem is the result image is not transparent, also I would like to have in the png image the alpha channel. This is my code: procedure TForm1.Button1Click(Sender: TObject); var png:…
Max1298492
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Combination of Canvas.TransparentColor and Canvas.Draw with Opacity

i want to draw a bitmap on a canvas with opacity where the bitmap has a transparent color. i could create a bitmap with transparent color and draw it to a canvas i could create a bitmap and draw it to a canvas with opacity but i couldn't combine…
linluk
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How to make alpha transparent TImage in Delphi?

On the Form I have two TImages. TImage which is on the top should be transparent, so we can see what is underneath. How to change the level of TImage transparency? Example:
Srdjan Vukmirica
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How to draw a bitmap on a canvas, respecting alpha values of the bitmap?

background i have a master bitmap that i need to draw on it other bitmaps. the master bitmap has some semi-transparent pixels (pixels with variant values for the alpha channel) , so that the other bitmaps that are drawn on it should be merged with…
android developer
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Overlapping semi-transparent divs without alpha adding up?

Is there a way to have semi-transparent elements (divs) overlap, and have the overlapped area NOT add up the 2 alpha values...i.e. make a seamless overlap? So if div 1 and div 2 have 0.5 alpha, the area where they overlap would still have 0.5 alpha,…
cannotcompute
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WebGL: Will zero-alpha pixels in a texture necessarily update the depth buffer?

I'm trying to render a texture which has a mix of fully-transparent pixels, and fully-opaque pixels. It seems like my only option is to render them distance-wise back-to-front (after all fully opaque polygons), because even the fully-transparent…
Grumdrig
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How to create transparent png image from bitmap?

My task is: Create a TBitmap object. Fill it with transparent color (alpha = 0). Assign this bitmap to TPngImage. Save PNG file with alpha transparency. How can I do it in Delphi XE? var Png: TPngImage; X, Y: Integer; Bitmap: TBitmap; begin …
Andrew
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Android how to set opacity in bitmap xml

I need to create a bitmap resource via xml, like: But I need to set opacity to this…
Comic Sans MS Lover
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Copy image with alpha channel to clipboard with custom background color?

Code : private void Foo(Canvas canvas) { // The content is a bit larger... Size size = new Size(canvas.ActualWidth * 1.1, canvas.ActualHeight * 1.2); // Create a render bitmap and push the surface to it RenderTargetBitmap…
Byzod
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Replace transparent color in PHP

I have set of images. In this images exist green alpha color. I need replace that transparent color to another color (i want replace to white alpha color). Its my code: $img = imagecreatefrompng($path . $file); $white_color_transparent =…
yAnTar
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