[파이썬] matplotlib 이미지 처리와 `matplotlib`

matplotlib logo

matplotlib is a popular Python library for data visualization and can also be used for image processing tasks. With its versatile functionality and extensive support for various image formats, matplotlib is a powerful tool for manipulating and analyzing images.

In this blog post, we will explore some common image processing tasks that can be accomplished using matplotlib in Python.

Reading and displaying an image

To start with, let’s see how we can read an image using matplotlib and display it on a plot. We can use the imread() function to read an image file and the imshow() function to display it.

import matplotlib.pyplot as plt

# Read an image file
image = plt.imread('path/to/image.jpg')

# Display the image
plt.imshow(image)
plt.axis('off')
plt.show()

By default, imshow() displays the image using the RGB color space. However, matplotlib also supports other color spaces like grayscale and indexed color. We can specify the cmap parameter in imshow() to display the image in a specific color space.

import matplotlib.pyplot as plt

# Read an image file
image = plt.imread('path/to/image.jpg')

# Display the grayscale version of the image
plt.imshow(image, cmap='gray')
plt.axis('off')
plt.show()

Image manipulation

matplotlib provides a range of functions for manipulating images, including resizing, cropping, rotating, and flipping. These functions can be used together with the imshow() function to visualize the results.

import matplotlib.pyplot as plt
import matplotlib.image as mpimg
import numpy as np

# Read an image file
image = mpimg.imread('path/to/image.jpg')

# Resize the image
resized_image = np.resize(image, (height, width))

# Crop a region of interest
cropped_image = image[y_start:y_end, x_start:x_end]

# Rotate the image
rotated_image = np.rot90(image)

# Flip the image horizontally
flipped_image = np.fliplr(image)

# Display the manipulated images
fig, axs = plt.subplots(2, 2)

axs[0, 0].imshow(resized_image)
axs[0, 0].axis('off')

axs[0, 1].imshow(cropped_image)
axs[0, 1].axis('off')

axs[1, 0].imshow(rotated_image)
axs[1, 0].axis('off')

axs[1, 1].imshow(flipped_image)
axs[1, 1].axis('off')

plt.show()

These are just a few examples of the image manipulation capabilities provided by matplotlib. You can explore more functions and techniques in the matplotlib documentation.

Conclusion

In this blog post, we have seen how matplotlib can be used for various image processing tasks in Python. From reading and displaying images to manipulating and analyzing them, matplotlib provides a versatile and powerful set of tools for working with images. Whether you are a beginner or an experienced Python developer, matplotlib can help you achieve your image processing goals effectively.

If you are interested in learning more about matplotlib and its capabilities, I highly recommend checking out the official matplotlib documentation and exploring the various tutorials and examples provided. Happy image processing!