Wand local_contrast() function – Python

The local_contrast() function is an inbuilt function in the Python Wand ImageMagick library which is used to increase light-dark transitions within the image.

Syntax:

local_contrast(radius, strength)

Parameters: This function accepts two parameters as mentioned above and defined below: 

• radius: This parameter is used to store the size of the Gaussian operator. Default value is 10.0
• strength: This parameter is used to store the percentage of blur mask to apply. Default value is 12.5 and it can range from 0 to 100.

Return Value: This function returns the Wand ImageMagick object.

Original Image:

Example 1:

Python3

# Import library from Image
from wand.image import Image

# Import the image
with Image(filename ='../geeksforgeeks.png') as image:
    # Clone the image in order to process
    with image.clone() as local_contrast:
        # Invoke local_contrast function with radius 12 and sigma 3
        local_contrast.local_contrast(12, 3)
        # Save the image
        local_contrast.save(filename ='local_contrast1.jpg')

Output:

Example 2:

Python3

# Import libraries from the wand
from wand.image import Image
from wand.drawing import Drawing
from wand.color import Color

with Drawing() as draw:
    # Set Stroke color the circle to black
    draw.stroke_color = Color('black')
    # Set Width of the circle to 2
    draw.stroke_width = 1
    # Set the fill color to 'White (# FFFFFF)'
    draw.fill_color = Color('white')

    # Invoke Circle function with center at 50, 50 and radius 25
    draw.circle((200, 200), # Center point
                (100, 100)) # Perimeter point
    # Set the font style
    draw.font = '../Helvetica.ttf'
    # Set the font size
    draw.font_size = 30

    with Image(width = 400, height = 400, background = Color('# 45ff33')) as pic:
        # Set the text and its location
        draw.text(int(pic.width / 3), int(pic.height / 2), 'GeeksForGeeks !')
        # Draw the picture
        draw(pic)
        # Invoke local_contrast function with radius 15 and sigma 78
        pic.local_contrast(15, 78)
        # Save the image
        pic.save(filename ='local_contrast2.jpg')

Output: