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Questions tagged [contrast]

the difference in color and light between parts of an image

281 questions
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Controlling Contrast and Brightness of Video Stream in OpenCV and Python

I’m using OpenCV3 and Python 3.7 to capture a live video stream from my webcam and I want to control the brightness and contrast. I cannot control the camera settings using OpenCV's cap.set(cv2.CAP_PROP_BRIGHTNESS, float) and…
slalomchip
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Text-only version vs. colour switcher for accessibility

Talking about website accessibility, you can have a text-only version of the site or just a color switcher for blind users, for example, to make its contrast more prominent, and therefore, easier to read. But my question is, what are the pros and…
Mika
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How to create a table like contrasts in r

I need help converting a dataframe with certain values into columns that looks like contrasts in R. For example. code <- data.frame(code = c('R1111', 'R1112', 'R1111', 'R1111', 'R1113', 'R1112', 'R1112', 'R1112',…
user6401955
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Equalize contrast and brightness across multiple images

I have roughly 160 images for an experiment. Some of the images, however, have clearly different levels of brightness and contrast compared to others. For instance, I have something like the two pictures below: I would like to equalize the two…
A.Rainer
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Android Bitmap Contrast Implementation

I want to create an app which applies contrast to an image and then displaying that image in ImageView. I found this example code and it doesn't seem to work properly. After applying the contrast it just makes everything greeny. Here is what I have…
dephinera
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High Contrast 'overflowing'

I'm using Windows 8.1 Pro 64-bit and whenever I use a high contrast theme, it leaks out into Eclipse, making it look high contrast, too. Here's a pic with the issue i'm having https://i.stack.imgur.com/Nm1Gh.png I was wondering if I can somehow…
user3927346
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Increase image contrast using look up table in MATLAB

I am trying to do some image processing for which I am given an 8-bit grayscale image. I am supposed to change the contrast of the image by generating a lookup table that increases the contrast for pixel values between 50 and 205. I have generated a…
David Norman
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How to change screen contrast of my android device?

Servus! I am coding a demo for a prototype with a build in Z1 android phone watch. Problem is that the default contrast setting for its display is pretty bad. Depending on my brightness setting I can choose between black looks like grey or white…
Yannic Welle
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Calculating Brightness and Contrast similar to new Adobe Photoshop or Lightroom functions

I am trying to create Brightness and Contrast filters similar to new Adobe Photoshop or Lightroom Brightness and Contrast filters. I am doing RGB -> XYZ - xyY conversion and with increasing pixel Brightness (Y) ( not linear increase, Brightness…
Zole
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R: loop / function to create a matrix for comparison (contrasts)

I have following type of data, means combination of factors P1 <- c("a", "a", "a", "a", "b", "b", "b", "c", "c", "d") P2 <- c("a", "b", "c", "d", "b", "c", "d", "c", "d", "d") myfactors <- data.frame(P1, P2) P1 P2 1 a a 2 a b 3 a c 4 …
jon
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What is the best contrast for abdominal CT scans?

I need to preprocess some abdominal CT scans in order to segment the spleen. What contrast function do you usually use for soft tissues in abdominal CT scans? I am working in Python and I tried histogram equalization, contrast stretching, but I am…
Flavia-Ioana Gheorghe
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Increase Contrast 50% by using vanilla javascript

I'm looking for a formula or something with which i can increase the contrast +50% of the image and can save it. I have tried Caman.js and its letting me increase contrast by numerical values and I can't figure out what level is 50%
average guy
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Computing a contrast map

I am trying to compute the contrast around each pixel in an NxN window and saving the results in a new image where each pixel in the new image is the contrast of the area around it in the old image. From another post I got this: 1) Convert the image…
user574362
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Adjust brightness and contrast OpenCV C++

I am trying to adjust the brightness and contrast of an RGB image but the output is not what I expect. The function is callbacked from createTrackbar() function with values from 0 to 100. Please check the image below. I would appreciate some help.…
Đinh Hồ Gia Bảo
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Measuring Contrast of an Image using Python

I have a code for brightness, and im currently looking into measuring contrast from PIL import Image from math import sqrt imag = Image.open("../Images/noise.jpg") imag = imag.convert ('RGB') imag.show() X,Y = 0,0 pixelRGB =…
Acryaz
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