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matplotlib example compare (snippet)

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Python matplotlib example 'compare'

Functions in program:

  • def compare_images(imageFileA, imageFileB, title):

Modules used in program:

  • import matplotlib.image
  • import matplotlib.pyplot
  • import skimage.measure
  • import matplotlib

python compare

Python matplotlib example: compare

# http://www.pyimagesearch.com/2014/09/15/python-compare-two-images/
# scikit-image: http://scikit-image.org
# pip3 install -U scikit-image

import matplotlib
matplotlib.use('TkAgg')

import skimage.measure
import matplotlib.pyplot
import matplotlib.image

def compare_images(imageFileA, imageFileB, title):
    # load the images
    imageA = matplotlib.image.imread(imageFileA)
    imageB = matplotlib.image.imread(imageFileB)

    # http://scikit-image.org/docs/stable/api/skimage.measure.html
    n = skimage.measure.compare_nrmse(imageA, imageB)
    p = skimage.measure.compare_psnr(imageA, imageB)
    s = skimage.measure.compare_ssim(imageA, imageB, multichannel=True)

    # setup the figure
    fig = matplotlib.pyplot.figure(title, figsize=(7, 7))
    matplotlib.pyplot.suptitle("NRMSE: %.2f, PSNR: %.2f, SSIM: %.2f" % (n, p, s))

    # show first image
    ax = fig.add_subplot(1, 2, 1)
    matplotlib.pyplot.imshow(imageA)
    matplotlib.pyplot.axis("off")

    # show the second image
    ax = fig.add_subplot(1, 2, 2)
    matplotlib.pyplot.imshow(imageB)
    matplotlib.pyplot.axis("off")

    # show the images
    matplotlib.pyplot.show()

# compare the images
compare_images("images/apple.jpg", "images/orange.jpg", "Original vs. Contrast")