Python Pillow - ImageChops.invert() Function

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In the Python image processing library Pillow (PIL), the invert function, located in the ImageOps module, provides a convenient way to perform negative-positive inversion of pixel values in an image.

This PIL.ImageChops.invert function is used to invert the pixel values of an image or channel. It calculates the inverted values by subtracting each pixel value from the maximum possible pixel value. The operation is implemented as follows −

$$\mathrm{out\:=\:MAX\:−\:image}$$

Syntax

Following is the syntax of the function −

PIL.ImageChops.invert(image)

Parameters

Here are the details of this function parameters −

• image − The input image whose pixel values will be inverted.

Return Value

The return type of this function is an Image.

Examples

Example 1

Here is an example that uses the ImageChops.invert() function on a JPEG image file to perform negative-positive inversion of pixel values in an image.

from PIL import Image, ImageChops

# Open a PNG image file
original_image = Image.open('Images/Car_2.jpg')

# Invert the pixel values of the image
inverted_image = ImageChops.invert(original_image)

# Display the input and resulting images
original_image.show()
inverted_image.show()

Output

Input Image

Output Image

Example 2

Here's an example demonstrating the pixel values before and after applying ImageChops.invert() to the input image of type BMP.

from PIL import Image, ImageChops

# Open an image file
original_image = Image.open('Images/lena.bmp')

# Display the pixel values before inversion
print("Pixel values in the original image at (0, 0) before inversion:", original_image.getpixel((0, 0)))

# Apply the ImageChops.invert() function to invert pixel values
inverted_image = ImageChops.invert(original_image)

# Display the pixel values after inversion
print("Pixel values in the inverted image at (0, 0) after inversion:", inverted_image.getpixel((0, 0)))

# Display the input and resulting images
original_image.show()
inverted_image.show()

Output

Input Image

Output Image

Example 3

The following example demonstrates how to apply the inversion operation on a single channel of an RGB image using the ImageChops.invert() function.

from PIL import Image, ImageChops

# Open an image file
original_image = Image.open('Images/flowers.jpg')

# Split the channels of the image
red, green, blue = original_image.split()

# Invert the green channel
inverted_green_channel = ImageChops.invert(green)

# Merge the channels back into an RGB image
image_with_inverted_green = Image.merge('RGB', (red, inverted_green_channel, blue))

# Display the input and resulting images
original_image.show()
image_with_inverted_green.show()

Output

Input Image

Output Image