Implementation of a Django ImageField that converts all images to JPEG

jpegfield.py

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)
        
        return super(JPEGImageFieldFile, self).save(name, content, save)


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

models.py

from django import models

class SimpleModel(models.Model):
   the_field = models.FileField()