使用请求库临时检索图像

Question

我正在编写一个网络刮刀,而不是只需要从网址中抓取图像的缩略图.

这是我的函数,使用urlib库.

def create_thumb(self):
    if self.url and not self.thumbnail:
        image = urllib.request.urlretrieve(self.url)

        # Create the thumbnail of dimension size
        size = 350, 350
        t_img = Imagelib.open(image[0])
        t_img.thumbnail(size)

        # Get the directory name where the temp image was stored
        # by urlretrieve
        dir_name = os.path.dirname(image[0])

        # Get the image name from the url
        img_name = os.path.basename(self.url)

        # Save the thumbnail in the same temp directory
        # where urlretrieve got the full-sized image,
        # using the same file extention in os.path.basename()
        file_path = os.path.join(dir_name, "thumb" + img_name)
        t_img.save(file_path)

        # Save the thumbnail in the media directory, prepend thumb
        self.thumbnail.save(
            os.path.basename(self.url),
            File(open(file_path, 'rb')))

由于各种原因,我需要更改它以使用请求库,什么是临时保存图像的等价物？

Answer 1

您可以跳过保存到临时文件部分并直接使用相应的响应对象来创建图像:

#!/usr/bin/env python3
import urllib.request
from PIL import Image # $ pip install pillow

im = Image.open(urllib.request.urlopen(url))
print(im.format, im.mode, im.size)

这是requests模拟的:

#!/usr/bin/env python
import requests # $ pip install requests
from PIL import Image # $ pip install pillow

r = requests.get(url, stream=True)
r.raw.decode_content = True # handle spurious Content-Encoding
im = Image.open(r.raw)
print(im.format, im.mode, im.size)

我用Pillow2.9.0和requests2.7.0 进行了测试.它应该从Pillow2.8开始工作.

Answer 2

您可以写入 io.BytesIO：

import requests

from PIL import Image
from io import BytesIO

r = requests.get(self.url)
b = BytesIO(r.content)
size = 350, 350
img = Image.open(b)
img.thumbnail(size)
img.save("foo.thumbnail", "JPEG")