PIL's ImageFilter module's filter function can also be used to find and enhance edges in an image. The following code block shows an example with the UMBC library image as input:
from PIL.ImageFilter import (FIND_EDGES, EDGE_ENHANCE, EDGE_ENHANCE_MORE)im = Image.open('../images/umbc_lib.jpg')pylab.figure(figsize=(18,25))pylab.subplot(2,2,1)plot_image(im, 'original (UMBC library)')i = 2for f in (FIND_EDGES, EDGE_ENHANCE, EDGE_ENHANCE_MORE): pylab.subplot(2,2,i) im1 = im.filter(f) plot_image(im1, str(f)) i += 1pylab.show()
The following screenshot shows the output of the preceding code with different edge finding/enhancing filters:
