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Questions tagged [pixel]

A pixel is the smallest unit that can be represented or controlled on a display. The word pixel is derived from the phrase "picture element".

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Does floating point length value make sense on pixel unit?

When I try write stylish CSS for forums.asterisk.org site, I saw they use floating point length value on pixel unit, for example: font-size: 13.1px;. As far as I known, pixel is the smallest unit in screen, so does floating point length value make…
LiuYan 刘研
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How to create and implement a pixel tracking code

OK, here's a goal I've been looking for a while. As it's known, most advertising and analytics companies use a so called "pixel" code in order to track websites views, transactions, conversion etc. I do have a general idea on how it works, the…
Andrei Stalbe
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How to draw a pixel on the screen in protected mode in x86 assembly?

I am creating a little bootloader+kernel and till now I managed to read disk, load second sector, load GDT, open A20 and enable pmode. I jumped to the 32-bits function that show me a character on the screen, using the video memory for textual…
ali
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C# Getting the pixel data efficiently from System.Drawing.Bitmap

I have several (~2GB) raw 24bpp RGB files on HDD. Now I want to retrieve a portion of it and scale it to the desired size. (The only scales allowed are 1, 1/2, 1/4, 1/8, ..., 1/256) So I'm currently reading every line from the rectangle of interest…
Arokh
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How to convert Android's DP to Flutter's LP? What is the difference between DP and LP?

I got the designs for a new app. All the dimensions are Android-ready and are given in DP - (Density-independent Pixels). How can I convert these values to Flutter's LP (Logical Pixels). I know that Window.devicePixelRatio gives me the number of…
kosiara - Bartosz Kosarzycki
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Why does Bootstrap use a 0.02px difference between screen size thresholds in its media queries?

// Extra small devices (portrait phones, less than 576px) @media (max-width: 575.98px) { ... } // Small devices (landscape phones, 576px and up) @media (min-width: 576px) and (max-width: 767.98px) { ... } // Medium devices (tablets, 768px and…
clickbait
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Convert lat/lon to pixels and back

I'm using google maps in my application, and I have a webserver with a databse filled with lat/lon values. I want to mark them on the map, but I also want to cluster them together if they are within a certain pixel-distance of eachother. I figure if…
AmITheRWord
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How to define clear range for pixel color

What I'm trying to do is to test if a pixel is blue or not. For example: The blue color is in RGB defined as rgb(0,0,255). Typical color depths are 8 bit (256 colours), 16 bit (about 65 thousand), 24 bit (about 16 million) and 32 bit (over 4 billion…
Jürgen K.
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How to draw OpenCL calculated pixels to the screen with OpenGL?

I wan't to do some calculated pixelart with OpenCL and display this directly on the display without CPU roundtripping. I could use interoperability of OpenCL with OpenGL and write to the texture-banks of the GPU and display the texture with OpenGL.…
RobotRock
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Mac OS Cocoa: Draw a simple pixel on a canvas

I wish I would find an answer for this. I have searched and searched and couldn't the right answer. Here is my situation: In a Mac OS Cocoa Application, I want to draw a pixel (actually a few pixels) onto a dedicated area on my application window. I…
Roman
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How to change the pixel values of an Image?

I am working on an Image Processing Project and I am a beginner at Python and using PIL. Any help would be appreciated. So, what I am doing is, I have an image of space with stars and noise. What I want to do is keep only the brighter pixels and…
Manshi Sanghai
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How to calculate the average color of a UIImage?

I want to build an app that lets the user select an image and it outputs the "average color". For example, this image: The average color would be a greenish/yellowish color. At the moment, I got this code: // In a UIColor extension public static…
Sweeper
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Android background image size in pixel

I would like to create a background image for different resolutions in Android. So I need the values (in pixel) for ldpi, mdpi, hdpi,xhdpi and xxhdpi. It is important that the image will not be blurred. I have already read the Documentation about…
JavaForAndroid
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Draw image from pixel array on canvas with putImageData

I am working on a project that can encrypt an image and redraw the decrypted image on canvas. As I am still pretty new to coding and programming, I am currently having issues redrawing the decrypted image data, which is a pixel array in the form…
Elias Pedersen
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How to access pixel values of CV_32F/CV_64F Mat?

I was working on homography and whenever I try to check the values of H matrix (type CV_64F) using H.at(i, j) I get random numbers(sometimes garbage value). I want to access pixel values of float matrix. Is there any way to do it? Mat A =…
Froyo
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