Thanks for hint. Here is my working solution. It takes lot of time. def __call__(self, value):
import Image import cgi import tempfile try: im = Image.open(value.file) print im.size, im.format im.thumbnail((100, 100), Image.ANTIALIAS) resized = tempfile.TemporaryFile() im.save(resized, im.format) value.file = resized value.file.seek(0) return (value, None) except Exception as e: print 'resize exception:', e return (value, self.error_message) - In-value in __call__ is just one Field of cgi.FieldStorage. Here is upload filed. In value.file is open file with uploaded data. - Final image is stored in tempfile.TemporaryFile(). It must be rewind before return! - __call__ return Field of cgi.FieldStorage with new value.file On 1 zář, 23:25, mdipierro <mdipie...@cs.depaul.edu> wrote: > This is a bit more complex than it seems because upload expects a > ci.FieldStorage object so the validator __call__ should return a > cgi.FieldStoarge. > > On Sep 1, 3:50 pm, kachna <petr.marti...@gmail.com> wrote: > > > > > Hi, > > I am trying to write validator to resize my image before storing in DB > > field. > > > class RESIZE_IMG(object): > > def __init__(self, isThumb=False, error_message='unresizable'): > > (self.isThumb, self.error_message) = (isThumb, > > error_message) > > > def __call__(self, value): > > import Image > > > try: > > > im = Image.open(value.file) > > # This print is OK. PIL recognize uploaded image > > print im.size, im.format > > > im.resize((100, 100)) > > value.file.seek(0) > > im.save(value.file, im.format) > > return (value, None) > > except Exception as e: > > print 'resize exception:', e > > return (value, self.error_message) > > > Script runs well but data in DB field is no image data. It can' t be > > displayed by download function from default controller too. > > > Thanks for help.