问题描述
我已经能够过滤出页面中的所有图片网址，并将它们一个接一个地显示
import requests
from bs4 import BeautifulSoup
article_URL = "https://medium.com/bhavaniravi/build-your-1st-python-web-app-with-flask-b039d11f101c"
response = requests.get(article_URL)
soup = bs4.BeautifulSoup(response.text,'html.parser')
images = soup.find('body').find_all('img')
i = 0
image_url = []
for im in images:
print(im)
i+=1
url = im.get('src')
image_url.append(url)
print('Downloading: ',url)
try:
response = requests.get(url,stream=True)
with open(str(i) + '.jpg','wb') as out_file:
shutil.copyfileobj(response.raw,out_file)
del response
except:
print('Could not download: ',url)
new = [x for x in image_url if x is not None]
for url in new:
resp = requests.get(url,stream=True).raw
image = np.asarray(bytearray(resp.read()),dtype="uint8")
image = cv2.imdecode(image,cv2.IMREAD_COLOR)
# height,width,channels = image.shape
height,_ = image.shape
dimension = []
for items in height,width:
dimension.append(items)
# print(height,width)
print(dimension)
我想从网址列表中打印尺寸最大的图像
这是我从列表中得到的结果，这还不够好
[72,72]
[95,96]
[13,60]
[227,973]
[17,60]
[229,771]
解决方法
我看到两个问题。
-
您可以在循环内创建
public partial class Form1 : Form { private ICipherDecipher myCipher; public Form1() { myCipher = new MyCipher(); InitializeComponent(); } private void button1_Click(object sender,EventArgs e) { string textToBeCiphered = textBox1.Text; string textCiphered = myCipher.Cipher(textToBeCiphered); textBox2.Text = textCiphered; } }，以便删除先前的值。您必须在循环和内部循环使用之前创建dimention = []dimention = []在循环之后，您可以使用
dimension.append( (width,height) )与最大max(dimension)配对 -
您在
width中仅保留width,height，因此您不知道哪个文件有此尺寸。您应该保留所有信息dimension
我的版本。
我使用字典dimension.append( (width,height,url,filename) )
保留所有信息
data然后我在data.append({
'url': url,'path': filename,'width': width,'height': height,})
中使用key来获得最大为max()的物品
width但我可以使用max(data,key=lambda x:x['width'])
或x['height']
x['width'] * x['height'] 顺便说一句：：仅使用import requests
from bs4 import BeautifulSoup
import shutil
import cv2
article_URL = "https://medium.com/bhavaniravi/build-your-1st-python-web-app-with-flask-b039d11f101c"
response = requests.get(article_URL)
soup = BeautifulSoup(response.text,'html.parser')
images = soup.find('body').find_all('img')
# --- loop ---
data = []
i = 0
for img in images:
print('HTML:',img)
url = img.get('src')
if url: # skip `url` with `None`
print('Downloading:',url)
try:
response = requests.get(url,stream=True)
i += 1
url = url.rsplit('?',1)[0] # remove ?opt=20 after filename
ext = url.rsplit('.',1)[-1] # .png,.jpg,.jpeg
filename = f'{i}.{ext}'
print('Filename:',filename)
with open(filename,'wb') as out_file:
shutil.copyfileobj(response.raw,out_file)
image = cv2.imread(filename)
height,width = image.shape[:2]
data.append({
'url': url,})
except Exception as ex:
print('Could not download: ',url)
print('Exception:',ex)
print('---')
# --- after loop ---
print('max:',max(data,key=lambda x:x['width']))
all_sorted = sorted(data,key=lambda x:x['width'],reverse=True)
print('Top 3:',all_sorted[:3])
# or
for item in all_sorted[:3]:
print(item['width'],item['url'])
src在创建新数组之后，立即在代码中进行以下更改：
images = []
for url in new:
resp = requests.get(url,stream=True).raw
image = np.asarray(bytearray(resp.read()),dtype="uint8")
image = cv2.imdecode(image,cv2.IMREAD_COLOR)
images.append((image.shape,image))
# sort images by area (largest to smallest)
images.sort (key = lambda x: x[0][0] * x[0][1],reverse=True)
最大图像现在位于索引0处，可以通过images [0] [1]进行访问，并且可以使用images [0] [0]打印其形状。您也可以将lambda函数更改为x [0] [0]（按高度排序）或x [0] [1]（按宽度排序）。