Wand canny() function – Python

The canny() function is an inbuilt function in the Python Wand ImageMagick library which is used to detect edges by leveraging a multi-stage Canny algorithm.
Syntax:
canny(radius, sigma, lower_percent, upper_percent)Parameters: This function accepts two parameters as mentioned above and defined below:
- radius: This parameter stores the radius of the gaussian filter.
- sigma: This parameter stores the standard deviation of the gaussian filter.
- lower_percent: This parameter which stores the normalized lower threshold.
- upper_percent: This parameter which stores the normalized upper threshold.
Return Value: This function returns the Wand ImageMagick object.
Original Image:
Example 1:
Python3
| # Import library from Image fromwand.image importImage# Import the imagewith Image(filename ='../zambiatek.png') as image:    # Clone the image in order to process    with image.clone() as canny:        # Invoke canny function         canny.canny(3, 2, 0.2, 0.8)        # Save the image        canny.save(filename ='canny1.jpg') | 
Output:
Example 2:
Python3
| # Import libraries from the wand  fromwand.image importImagefromwand.drawing importDrawingfromwand.color importColorwith 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 canny function        pic.canny(4, 2, 0.3, 0.7)        # Save the image         pic.save(filename ='canny2.jpg') | 
Output:
 
				 
					



