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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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pixel.gif, why do people use it?

Just a simple question, why is pixel.gif usefull? And why should you use it or why not?
Thew
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How can I simply load a greyscale tiff in libtiff and get an array of pixel intensities?

I am trying to understand images some more, and I'm having a great deal of trouble. From using matlab, I have experience in using imread('test.tif'), and getting a beautiful matrix of rows vs. columns, where you have the intensity of each pixel as…
The_Anomaly
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Poor results with source-over alpha blending (HTML5 canvas)

Edit: I don't necessarily need a solution to this problem--rather I'd like to understand why it's occurring. I don't see why I should be getting the odd results below... Although this question is directed towards an issue I'm having with an HTML5…
Xenethyl
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How to convert RGB image pixels to L*a*b*?

Well, I'm working with image processing to identify the color variation of an image and to be able to plot that data in a histogram. For this, I use images of skin spots in the RGB color space. The code below I can get the colors of each pixel and…
Tecnologia da Net
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C++ 2D pixel perfect collision detection libraries?

what are the libraries available to do this which integrate with SDL and QT4 . Are there any existing packages in SDL or QT which allow for easy implementation of this?. I am looking for for an easy to use library that would allow me to have a…
Aditya P
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Python Opencv - Cannot change pixel value of a picture

Need to change the white pixels to black and black pixels to white of the picture given below import cv2 img=cv2.imread("cvlogo.png") A basic opencv logo with white background and resized the picture to a fixed known size …
Sundaramoorthy Anandh
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Dynamically Generate Transparent Tracking Pixel

I'm trying to generate a clear tracking pixel dynamically in Java, but running into some issues. I have no problem returning this to the user, but I can't seem to get the pixel right. What am I doing wrong? This is what I have, which gives me a 1x1…
tau-neutrino
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Drawing aliased, pixel-perfect 1px splines (Catmull-Rom, specifically)

A brief background: I'm working on a web-based drawing application and need to draw 1px thick splines that pass through their control points. The issue I'm struggling with is that I need to draw each of the pixels between p1 and p2 as if I were…
Xenethyl
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python - opencv - convert pixel from bgr to hsv

img = cv2.imread('example.jpg') img_hsv = cv2.cvtColor(img, cv2.COLOR_BGR2HSV) # lower mask (0-10) lower_red = np.array([0, 50, 50]) upper_red = np.array([10, 255, 255] mask0 = cv2.inRange(img_hsv, lower_red, upper_red) # upper mask…
cmplx96
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Area covered with the same pixel colour and change it

how to erase the colour of particular pixel and pixel area covered with the same colour.I am able to get the particular pixel colour using below swift code but I am not able to get surrounding area which has same colour pixel and unable to erase…
Uttam
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Help with the theory behind a pixelate algorithm?

So say I have an image that I want to "pixelate". I want this sharp image represented by a grid of, say, 100 x 100 squares. So if the original photo is 500 px X 500 px, each square is 5 px X 5 px. So each square would have a color corresponding to…
Oliver
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Pixelated lighting shader

I've written a GLSL shader for use in Unity3D with my pixelated iOS app. It has two ONE problems: 1) The effect doesn't always stay with the moon, and 2) the lighting doesn't look pixelated. I'll explain a little. The shader is meant to cause a…
Catlard
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Selecting the pixels with highest intensity in OpenCV

Can anyone help me to find out the top 1% (or say top 100 pixels)brightest pixels with their locations of a gray image in opencv. because cvMinMaxLoc() gives only brightest pixel location. Any help is greatly appreciated.
Dark Knight
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iOS 9.3 Color Management / Profiles

I have many apps that rely on rgb value checking based on tapped pixels. If I tap a pixel that returns 128/128/138 then it opens up this particular thing from an array. With 9.3 this no longer works as I am getting crazy color values returned. I did…
malaki1974
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iOS WKWebView get RGBA pixel color from point

How can I get the RGBA pixel color of a point from a WKWebView? I have a working solution for the UIWebView, but I would like to use the WKWebView instead. When I tap on a point of the screen I'm able to retrieve the color value in RGBA from the…
Tassilo Waldraff
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