How to save an image locally using Python whose URL address I already know?

Question

Python 2

Here is a more straightforward way if all you want to do is save it as a file:

import urllib

urllib.urlretrieve("http://www.digimouth.com/news/media/2011/09/google-logo.jpg", "local-filename.jpg")

The second argument is the local path where the file should be saved.

Python 3

As SergO suggested the code below should work with Python 3.

import urllib.request

urllib.request.urlretrieve("http://www.digimouth.com/news/media/2011/09/google-logo.jpg", "local-filename.jpg")

import urllib
resource = urllib.urlopen("http://www.digimouth.com/news/media/2011/09/google-logo.jpg")
output = open("file01.jpg","wb")
output.write(resource.read())
output.close()

file01.jpg will contain your image.

I wrote a script that does just this, and it is available on my github for your use.

I utilized BeautifulSoup to allow me to parse any website for images. If you will be doing much web scraping (or intend to use my tool) I suggest you sudo pip install BeautifulSoup. Information on BeautifulSoup is available here.

For convenience here is my code:

from bs4 import BeautifulSoup
from urllib2 import urlopen
import urllib

# use this image scraper from the location that 
#you want to save scraped images to

def make_soup(url):
    html = urlopen(url).read()
    return BeautifulSoup(html)

def get_images(url):
    soup = make_soup(url)
    #this makes a list of bs4 element tags
    images = [img for img in soup.findAll('img')]
    print (str(len(images)) + "images found.")
    print 'Downloading images to current working directory.'
    #compile our unicode list of image links
    image_links = [each.get('src') for each in images]
    for each in image_links:
        filename=each.split('/')[-1]
        urllib.urlretrieve(each, filename)
    return image_links

#a standard call looks like this
#get_images('http://www.wookmark.com')

This can be done with requests. Load the page and dump the binary content to a file.

import os
import requests

url = 'https://apod.nasa.gov/apod/image/1701/potw1636aN159_HST_2048.jpg'
page = requests.get(url)

f_ext = os.path.splitext(url)[-1]
f_name = 'img{}'.format(f_ext)
with open(f_name, 'wb') as f:
    f.write(page.content)

Python 3

urllib.request — Extensible library for opening URLs

from urllib.error import HTTPError
from urllib.request import urlretrieve

try:
    urlretrieve(image_url, image_local_path)
except FileNotFoundError as err:
    print(err)   # something wrong with local path
except HTTPError as err:
    print(err)  # something wrong with url

A solution which works with Python 2 and Python 3:

try:
    from urllib.request import urlretrieve  # Python 3
except ImportError:
    from urllib import urlretrieve  # Python 2

url = "http://www.digimouth.com/news/media/2011/09/google-logo.jpg"
urlretrieve(url, "local-filename.jpg")

or, if the additional requirement of requests is acceptable and if it is a http(s) URL:

def load_requests(source_url, sink_path):
    """
    Load a file from an URL (e.g. http).

    Parameters
    ----------
    source_url : str
        Where to load the file from.
    sink_path : str
        Where the loaded file is stored.
    """
    import requests
    r = requests.get(source_url, stream=True)
    if r.status_code == 200:
        with open(sink_path, 'wb') as f:
            for chunk in r:
                f.write(chunk)

I made a script expanding on Yup.'s script. I fixed some things. It will now bypass 403:Forbidden problems. It wont crash when an image fails to be retrieved. It tries to avoid corrupted previews. It gets the right absolute urls. It gives out more information. It can be run with an argument from the command line.

# getem.py
# python2 script to download all images in a given url
# use: python getem.py http://url.where.images.are

from bs4 import BeautifulSoup
import urllib2
import shutil
import requests
from urlparse import urljoin
import sys
import time

def make_soup(url):
    req = urllib2.Request(url, headers={'User-Agent' : "Magic Browser"}) 
    html = urllib2.urlopen(req)
    return BeautifulSoup(html, 'html.parser')

def get_images(url):
    soup = make_soup(url)
    images = [img for img in soup.findAll('img')]
    print (str(len(images)) + " images found.")
    print 'Downloading images to current working directory.'
    image_links = [each.get('src') for each in images]
    for each in image_links:
        try:
            filename = each.strip().split('/')[-1].strip()
            src = urljoin(url, each)
            print 'Getting: ' + filename
            response = requests.get(src, stream=True)
            # delay to avoid corrupted previews
            time.sleep(1)
            with open(filename, 'wb') as out_file:
                shutil.copyfileobj(response.raw, out_file)
        except:
            print '  An error occured. Continuing.'
    print 'Done.'

if __name__ == '__main__':
    url = sys.argv[1]
    get_images(url)