How to resize the new uploaded images using PIL before saving?

Question

I want to resize the new images in a height and width of 800px and save them. And the app mustn't store the real image. Any help?

This is my code, it saves the original image and don't the resized photo:

models.py:

class Photo(models.Model):        
    photo = models.ImageField(upload_to='photos/default/')


    def save(self):

        if not self.id and not self.photo:
            return            

        super(Photo, self).save()

        image = Image.open(self.photo)
        (width, height) = image.size

        "Max width and height 800"        
        if (800 / width < 800 / height):
            factor = 800 / height
        else:
            factor = 800 / width

        size = ( width / factor, height / factor)
        image.resize(size, Image.ANTIALIAS)
        image.save(self.photo.path)

Answer 1

image = image.resize(size, Image.ANTIALIAS)

resize is non-destructive, it returns a new image.

Answer 2

I use django-resized for my projects.