[Doitsu]

Originally Posted by CalibUser

Thanks, Doitsu, this method allows me to read an image from an epub into img. After resizing the image, how can I write it back in a format that bk.writefile() can use? I've tried a few approaches including bkimage = BytesIO(self.img ) but without success.

AFAIK, you'll have to use BytesIO.

from PIL import Image
from io import BytesIO

def run(bk):
    data = bk.readfile('cover.jpg')
    img = Image.open(BytesIO(data))
    img.thumbnail((330, 330), Image.ANTIALIAS)
    imagedata = BytesIO()
    img.save(imagedata, 'png')
    thumbnail = imagedata.getvalue()
    bk.addfile('thumbnail.png', 'thumbnail.png', thumbnail, 'image/png')

(For some odd reason img.save() doesn't appear to work with jpg as the file format.)