47 lines
1.4 KiB
Python
47 lines
1.4 KiB
Python
"""Project 2 tools for generating a noisy image"""
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import matplotlib.pyplot as plt
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import numpy as np
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from PIL import Image # PIL is an image processing module
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def create_noisy_image(path="/content/drive/My Drive/", file="sonic.jpg"):
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"""Transform color image to a noisy grayscale image.
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Plot and save the transformed images.
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The file sonic.jpg must be located in your google drive and the drive must have been
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"mounted" with:
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from google.colab import drive
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drive.mount("/content/drive")
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"""
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image = Image.open(path + file)
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# Transform RGB image to grayscale
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image = image.convert("L")
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# get the filename without the extension
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# (note: the pathlib module offers better ways to do this!)
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name = file.removesuffix(".jpg")
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image.save(path + name + "_gray.jpg")
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# set images to be plotted in gray scale
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plt.gray()
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plt.imshow(image)
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plt.title("Original image")
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plt.show()
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# add noise to grayscale image
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sigma = 2.0
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img_arr = np.array(image)
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img_arr_noisy = np.clip(
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img_arr + sigma * np.random.normal(0, 100, img_arr.shape), 0, 255
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).astype(np.uint8)
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plt.title("Noisy image")
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plt.imshow(img_arr_noisy)
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# create Image object from numpy array and save to disk
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image = Image.fromarray(img_arr_noisy, mode="L")
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image.save(path + name + "_gray_noisy.jpg")
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plt.show()
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