In analyzing images, the first step is to convert colors into numerical values. Matplotlib provides APIs to read and show an image matrix of RGB values.
The following is a quick code example of reading an image into a NumPy array with plt.imread('image_path'), and we show it with plt.imshow(image_ndarray). Make sure that the Pillow package is installed so that more image types other than PNG can be handled:
import matplotlib.pyplot as plt
# Source image downloaded under CC0 license: Free for personal and commercial use. No attribution required.
# Source image address: https://pixabay.com/en/rose-pink-blossom-bloom-flowers-693155/
img = plt.imread('ch04.img/mpldev_ch04_rose.jpg')
plt.imshow(img)Here is the original image displayed with the preceding code:
After showing the original image, we will try to work with transforming the image by changing the color values in the image matrix. We will create a high-contrast image by setting the RGB values to either 0 or 255 (max) at the...