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andrewgiessel/gist:4589258

Created January 21, 2013 20:52
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histogram normalization with numpy
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gistfile1.txt
import numpy as np
def histeq(im,nbr_bins=256):
#get image histogram
imhist,bins = np.histogram(im.flatten(),nbr_bins,normed=True)
cdf = imhist.cumsum() #cumulative distribution function
cdf = 255 * cdf / cdf[-1] #normalize
#use linear interpolation of cdf to find new pixel values
im2 = np.interp(im.flatten(),bins[:-1],cdf)
return im2.reshape(im.shape), cdf
@Bhisham-Sharma
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how to interpolate a CDF at a value say 0.5 to get a scalar value as a result?

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