Python PIL Outline image increase thicknesses

Question

I know how to find the edges from a picture. But I would like to have the outline edges be thicker for example width 9.

    from PIL import Image, ImageFilter

    image = Image.open('your_image.png')
    image = image.filter(ImageFilter.FIND_EDGES, width=9)
    image.save('new_name.png') 

is that possible?

Answer 1

You can find edges and fatten them like this:

#!/usr/bin/env python3

from PIL import Image, ImageMorph, ImageFilter

# Open star image and ensure greyscale
im = Image.open('star.png').convert('L')

# Detect edges and save
edges = im.filter(ImageFilter.FIND_EDGES)
edges.save('DEBUG-edges.png')

# Make fatter edges and save
fatEdges = edges.filter(ImageFilter.MaxFilter)
fatEdges.save('DEBUG-fatEdges.png')

# Make very fat edges and save
veryFatEdges = edges.filter(ImageFilter.MaxFilter(7))
veryFatEdges.save('DEBUG-veryFatEdges.png')

Top-left=original, top-right=edges, bottom-left=fat edges, bottom-right=very fat edges.

You could use ImageMorph module for more controlled morphology, but the maximum filter is very effective as it is.