Wand brightness_contrast() function – Python

The brightness_contrast() function is an inbuilt function in the Python Wand ImageMagick library which is used to change the brightness and contrast of the image.

Syntax:

brightness_contrast(brightness, contrast, channel)

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

• Brightness: This parameter is used to specify the value of brightness which lies in between -100 to 100. Default value is 0.
• Contrast: This parameter is used to specify the value of contrast which lies in between -100 to 100. Default value is 0.
• channel: This parameter is used to specify the value of image channel as undefined, ‘red’, ‘gray’, ‘cyan’, ‘green’, ‘magenta’, ‘blue’, ‘yellow’, ‘alpha’, ‘opacity’, ‘black’, ‘index’, ‘composite_channels’, ‘all_channels, ‘sync_channels’, ‘default_channels’.

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 brightness_contrast:
        # Invoke brightness_contrast function with brightness as 50, Contrast as 17
        # channel as Red
        brightness_contrast.brightness_contrast(int(50), int(17), 'Red')
        # Save the image
        brightness_contrast.save(filename ='brightness_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 brightness_contrast function with Brightness as -44, Contrast as 33
        # Channel as Red
        pic.brightness_contrast(int(-44), int(33), 'Red')
        # Save the image
        pic.save(filename ='brightness_contrast2.jpg')

Output: