Samples

With PIL(Pillow)

from PIL import Image
import piexif

im = Image.open(filename)
exif_dict = piexif.load(im.info["exif"])
# process im and exif_dict...
w, h = im.size
exif_dict["0th"][piexif.ImageIFD.XResolution] = (w, 1)
exif_dict["0th"][piexif.ImageIFD.YResolution] = (h, 1)
exif_bytes = piexif.dump(exif_dict)
im.save(new_file, "jpeg", exif=exif_bytes)

Check Containing Tag

from PIL import Image
import piexif

exif_dict = piexif.load(filename)
if piexif.ImageIFD.Orientation in exif_dict["0th"]:
    print("Orientation is ", exif_dict["0th"][piexif.ImageIFD.Orientation])
if piexif.ExifIFD.Gamma in exif_dict["Exif"]:
    print("Gamma is ", exif_dict["Exif"][piexif.ExifIFD.Gamma])

Rotate Image by Exif Orientation

Rotate image by exif orientation tag and remove orientation tag.

from PIL import Image
import piexif

def rotate_jpeg(filename):
    img = Image.open(filename)
    if "exif" in img.info:
        exif_dict = piexif.load(img.info["exif"])

        if piexif.ImageIFD.Orientation in exif_dict["0th"]:
            orientation = exif_dict["0th"].pop(piexif.ImageIFD.Orientation)
            exif_bytes = piexif.dump(exif_dict)

            if orientation == 2:
                img = img.transpose(Image.FLIP_LEFT_RIGHT)
            elif orientation == 3:
                img = img.rotate(180)
            elif orientation == 4:
                img = img.rotate(180).transpose(Image.FLIP_LEFT_RIGHT)
            elif orientation == 5:
                img = img.rotate(-90).transpose(Image.FLIP_LEFT_RIGHT)
            elif orientation == 6:
                img = img.rotate(-90)
            elif orientation == 7:
                img = img.rotate(90).transpose(Image.FLIP_LEFT_RIGHT)
            elif orientation == 8:
                img = img.rotate(90)

            img.save(filename, exif=exif_bytes)

Piexif on Server

Piexif loads exif data as dict from JPEG. Python dict is easy to convert to JSON, therefore piexif has a good compatible with AJAX, document oriented DB…

"""GoogleAppEngine and Python 2.7"""
import json

import tornado.web
import tornado.wsgi
import piexif


class PostHandler(tornado.web.RequestHandler):
    def post(self):
        jpg_data = self.request.body
        try:
            exif_dict = piexif.load(jpg_data)
        except:
            self.set_status(400)
            return self.write("Wrong jpeg")
        self.add_header("Content-Type", "application/json")
        thumbnail = exif_dict.pop("thumbnail")
        data_d = {}
        for ifd in exif_dict:
            data_d[ifd] = {piexif.TAGS[ifd][tag]["name"]:exif_dict[ifd][tag]
                           for tag in exif_dict[ifd]}
        data_d["thumbnail"] = thumbnail
        data = json.dumps(data_d, encoding="latin1")
        return self.write(data)

application = tornado.web.Application([
    (r"/p", PostHandler),
])

application = tornado.wsgi.WSGIAdapter(application)