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In Python, how do I read the exif data for an image?

开发者 https://www.devze.com 2023-02-05 21:09 出处:网络
I\'m us开发者_如何学Cing PIL. How do I turn the EXIF data of a picture into a dictionary?You can use the _getexif() protected method of a PIL Image.

I'm us开发者_如何学Cing PIL. How do I turn the EXIF data of a picture into a dictionary?


You can use the _getexif() protected method of a PIL Image.

import PIL.Image
img = PIL.Image.open('img.jpg')
exif_data = img._getexif()

This should give you a dictionary indexed by EXIF numeric tags. If you want the dictionary indexed by the actual EXIF tag name strings, try something like:

import PIL.ExifTags
exif = {
    PIL.ExifTags.TAGS[k]: v
    for k, v in img._getexif().items()
    if k in PIL.ExifTags.TAGS
}


For Python3.x and starting Pillow==6.0.0, Image objects now provide a "public"/official getexif() method that returns a <class 'PIL.Image.Exif'> instance or None if the image has no EXIF data.

From Pillow 6.0.0 release notes:

getexif() has been added, which returns an Exif instance. Values can be retrieved and set like a dictionary. When saving JPEG, PNG or WEBP, the instance can be passed as an exif argument to include any changes in the output image.

As stated, you can iterate over the key-value pairs of the Exif instance like a regular dictionary. The keys are 16-bit integers that can be mapped to their string names using the ExifTags.TAGS module.

from PIL import Image, ExifTags

img = Image.open("sample.jpg")
img_exif = img.getexif()
print(type(img_exif))
# <class 'PIL.Image.Exif'>

if img_exif is None:
    print('Sorry, image has no exif data.')
else:
    for key, val in img_exif.items():
        if key in ExifTags.TAGS:
            print(f'{ExifTags.TAGS[key]}:{val}')
            # ExifVersion:b'0230'
            # ...
            # FocalLength:(2300, 100)
            # ColorSpace:1
            # ...
            # Model:'X-T2'
            # Make:'FUJIFILM'
            # LensSpecification:(18.0, 55.0, 2.8, 4.0)
            # ...
            # DateTime:'2019:12:01 21:30:07'
            # ...

Tested with Python 3.8.8 and Pillow==8.1.0.


You can also use the ExifRead module:

import exifread
# Open image file for reading (binary mode)
f = open(path_name, 'rb')

# Return Exif tags
tags = exifread.process_file(f)


I use this:

import os,sys
from PIL import Image
from PIL.ExifTags import TAGS

for (k,v) in Image.open(sys.argv[1])._getexif().items():
        print('%s = %s' % (TAGS.get(k), v))

or to get a specific field:

def get_field (exif,field) :
  for (k,v) in exif.items():
     if TAGS.get(k) == field:
        return v

exif = image._getexif()
print get_field(exif,'ExposureTime')


import sys
import PIL
import PIL.Image as PILimage
from PIL import ImageDraw, ImageFont, ImageEnhance
from PIL.ExifTags import TAGS, GPSTAGS



class Worker(object):
    def __init__(self, img):
        self.img = img
        self.exif_data = self.get_exif_data()
        self.lat = self.get_lat()
        self.lon = self.get_lon()
        self.date =self.get_date_time()
        super(Worker, self).__init__()

    @staticmethod
    def get_if_exist(data, key):
        if key in data:
            return data[key]
        return None

    @staticmethod
    def convert_to_degress(value):
        """Helper function to convert the GPS coordinates
        stored in the EXIF to degress in float format"""
        d0 = value[0][0]
        d1 = value[0][1]
        d = float(d0) / float(d1)
        m0 = value[1][0]
        m1 = value[1][1]
        m = float(m0) / float(m1)

        s0 = value[2][0]
        s1 = value[2][1]
        s = float(s0) / float(s1)

        return d + (m / 60.0) + (s / 3600.0)

    def get_exif_data(self):
        """Returns a dictionary from the exif data of an PIL Image item. Also
        converts the GPS Tags"""
        exif_data = {}
        info = self.img._getexif()
        if info:
            for tag, value in info.items():
                decoded = TAGS.get(tag, tag)
                if decoded == "GPSInfo":
                    gps_data = {}
                    for t in value:
                        sub_decoded = GPSTAGS.get(t, t)
                        gps_data[sub_decoded] = value[t]

                    exif_data[decoded] = gps_data
                else:
                    exif_data[decoded] = value
        return exif_data

    def get_lat(self):
        """Returns the latitude and longitude, if available, from the 
        provided exif_data (obtained through get_exif_data above)"""
        # print(exif_data)
        if 'GPSInfo' in self.exif_data:
            gps_info = self.exif_data["GPSInfo"]
            gps_latitude = self.get_if_exist(gps_info, "GPSLatitude")
            gps_latitude_ref = self.get_if_exist(gps_info, 'GPSLatitudeRef')
            if gps_latitude and gps_latitude_ref:
                lat = self.convert_to_degress(gps_latitude)
                if gps_latitude_ref != "N":
                    lat = 0 - lat
                lat = str(f"{lat:.{5}f}")
                return lat
        else:
            return None

    def get_lon(self):
        """Returns the latitude and longitude, if available, from the 
        provided exif_data (obtained through get_exif_data above)"""
        # print(exif_data)
        if 'GPSInfo' in self.exif_data:
            gps_info = self.exif_data["GPSInfo"]
            gps_longitude = self.get_if_exist(gps_info, 'GPSLongitude')
            gps_longitude_ref = self.get_if_exist(gps_info, 'GPSLongitudeRef')
            if gps_longitude and gps_longitude_ref:
                lon = self.convert_to_degress(gps_longitude)
                if gps_longitude_ref != "E":
                    lon = 0 - lon
                lon = str(f"{lon:.{5}f}")
                return lon
        else:
            return None

    def get_date_time(self):
        if 'DateTime' in self.exif_data:
            date_and_time = self.exif_data['DateTime']
            return date_and_time 

if __name__ == '__main__':
    try:
        img = PILimage.open(sys.argv[1])
        image = Worker(img)
        lat = image.lat
        lon = image.lon
        date = image.date
        print(date, lat, lon)

    except Exception as e:
        print(e)


I have found that using ._getexif doesn't work in higher python versions, moreover, it is a protected class and one should avoid using it if possible. After digging around the debugger this is what I found to be the best way to get the EXIF data for an image:

from PIL import Image

def get_exif(path):
    return Image.open(path).info['parsed_exif']

This returns a dictionary of all the EXIF data of an image.

Note: For Python3.x use Pillow instead of PIL


Here's the one that may be little easier to read. Hope this is helpful.

from PIL import Image
from PIL import ExifTags

exifData = {}
img = Image.open(picture.jpg)
exifDataRaw = img._getexif()
for tag, value in exifDataRaw.items():
    decodedTag = ExifTags.TAGS.get(tag, tag)
    exifData[decodedTag] = value


To read image url and get tags

from PIL import Image
from urllib.request import urlopen
from PIL.ExifTags import TAGS 


def get_exif(filename):
    image = Image.open(filename)
    image.verify()
    return image._getexif()

def get_labeled_exif(exif):
    labeled = {}
    for (key, val) in exif.items():
        labeled[TAGS.get(key)] = val

    return labeled

my_image= urlopen(url)

exif = get_exif(my_image)
labeled = get_labeled_exif(exif)
print(labeled)

and to get GPS coordinate, Jayson DeLancey has excellent blog post.


I usually use pyexiv2 to set exif information in JPG files, but when I import the library in a script QGIS script crash.

I found a solution using the library exif:

https://pypi.org/project/exif/

It's so easy to use, and with Qgis I don,'t have any problem.

In this code I insert GPS coordinates to a snapshot of screen:

from exif import Image
with open(file_name, 'rb') as image_file:
    my_image = Image(image_file)

my_image.make = "Python"
my_image.gps_latitude_ref=exif_lat_ref
my_image.gps_latitude=exif_lat
my_image.gps_longitude_ref= exif_lon_ref
my_image.gps_longitude= exif_lon

with open(file_name, 'wb') as new_image_file:
    new_image_file.write(my_image.get_file())
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