Is there an obvious way to do this that I\'m missing? I\'m just trying to make thumbnails.
Define a maximum size.
Then, compute a resize ratio by taking min(maxwidth/width, maxheight/height)
.
The proper size is oldsize*ratio
.
There is of course also a library method to do this: the method Image.thumbnail
.
Below is an (edited) example from the PIL documentation.
import os, sys
import Image
size = 128, 128
for infile in sys.argv[1:]:
outfile = os.path.splitext(infile)[0] + ".thumbnail"
if infile != outfile:
try:
im = Image.open(infile)
im.thumbnail(size, Image.ANTIALIAS)
im.save(outfile, "JPEG")
except IOError:
print "cannot create thumbnail for '%s'" % infile