Questions tagged [histogram-equalization]
23 questions
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Which channel I can use to convert hist image to color image?
This is the original image
Code for applying equalizeHist to image:
PhotoImage_hist = resized_img
hist_image = resized_img
def histogram():
global PhotoImage_hist,hist_image,gray_image
hist_image = cv2.equalizeHist(gray_image)
…
GALAXY A50
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How to calculate cdf(v) without loops - using numpy. For each pixel v, cdf(v) equals to the number of pixels with values lower or equal to v
The general histogram equalization formula for an 8-bit image is: h(v) = ((cdf(v) - cdf_min) / (M * N - cdf_min) * 255) where
cdf(v) is the cumulative distribution function. For each pixel v, cdf(v) equals to the number of pixels with values lower…
Pranav Pandey
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Does histogram equalization change the pixel intensity range? (16-bit)
Currently, I am doing histogram equalization on a 16 bit image, would the range change from [0, 65536] after the process?
import numpy as np
hist, bins = np.histogram(img.flatten(), 65536, [0, 65536]) # Collect 16 bits histogram (65536 = 2^16)
maximus
- 335
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Algorithm to determine how CLAHE should be applied most optimally
I need to run CLAHE on a bunch of images, but there are 3 ways of doing it;
CLAHE on each RGB channel (RGB)
CLAHE on L channel (LAB)
CLAHE on V channel (HSV)
I've found however, that all methods work on some photos, and all methods fails on others…
Lynet _101
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1 answer
How to use transformation T from histeq in Matlab?
The documentation of histeq in Matlab says:
[___,T] = histeq(___) also returns the transformation T that maps the gray component of the input grayscale image or colormap to the gray component of the output grayscale image or colormap.
How do I…
root
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Error in pupilFrame = cv2.equalizeHist(frame[y+(h*0.25):(y+h), x:(x+w)])
Hello i have this error in complation can any one helpe me please
##ERROR##
raceback (most recent call last):
File "C:\Users\ASUS\Desktop\PFE Master Eye Tracker 2021\PFE_Eye_Tracker_code\opencv-eye-tracking-master\eye_control.py", line 47, in…
0
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1 answer
Match template histogram with testing histogram
How can we calculate the percentage of similarities between two pattern of Histogram?
For example, I have a histogram of template which I called HistA, and I have another histogram which is HistB where I want to check the similarities percentage of…
syakey
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2 answers
How to apply histogram to the parts of an image and recompose the image again
How can to split image in parts, apply histogram equalization, compose an image form the parts and display it
I am trying to figure a way to split an image into defined number of parts, meaning the image is split into a number of rectangeles that…
kristian
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