Implementation of a Django ImageField that converts all images to JPEG

jpegfield.py

import os
from PIL import Image
import cStringIO

from django.core.files.base import ContentFile
from django.db.models import ImageField
from django.db.models.fields.files import ImageFieldFile

class JPEGImageFieldFile(ImageFieldFile):
    
    def save(self, name, content, save=True):
        if content:
            image = Image.open(content)
            if image.mode not in ('L', 'RGB'):
                image = image.convert("RGB")
            buf = cStringIO.StringIO()
            image.save(buf, format="JPEG")
            new_content_str = buf.getvalue()
            content = ContentFile(new_content_str)
            base, ext = os.path.splitext(name)
        return super(JPEGImageFieldFile, self).save('%s.jpg' % base, content, save)


class JPEGImageField(ImageField):
    """
    ImageField that converts all images to JPEG on save.
    """
    attr_class = JPEGImageFieldFile