如何在python中保存selenium和opencv的部分截图答案

【问题标题】：How to save partial screenshot from selenium and opencv in python如何在python中保存selenium和opencv的部分截图
【发布时间】：2018-06-14 04:36:37
【问题描述】：

我正在尝试使用 OpenCV 和 selenium 将 html 中的特定元素保存为图像文件。但无法保存文件。

from selenium import webdriver
import cv2
import numpy as np


browser = webdriver.Firefox()
browser.get(<URl with image>)

# Element to be saved
element = browser.find_element_by_id(<id of element>)

png = browser.get_screenshot_as_png()
location = element.location
size  = element.size

nparr = np.frombuffer(png, np.uint8)
img = cv2.imdecode(nparr, cv2.IMREAD_COLOR)


left = location['x']
top = location['y']
right = location['x'] + size['width']
bottom = location['y'] + size['height']

im = img[left:right, top:bottom]

cv2.imwrite('filename.png',im)

目前'filename.png'中没有图片数据通过运行这个脚本。

【问题讨论】：

能否调试left、top、right和bottom中存储的值
>>>print (left, top, right, bottom) >>>755 405 987.0 482.0
将right 和bottom 转换为整数会更好。你也可以调试print img.shape吗？这里要注意的一件事是您以错误的方式裁剪img numpy 矩阵，正确的做法是im= img[top:bottom, left:right]
感谢您解决了问题。
与How to take partial screenshot with Selenium WebDriver in python?重复

标签： python selenium numpy opencv crop

【解决方案1】：

正如@Zdar 所说，我正在编写以下解决方案：

from selenium import webdriver
import cv2
import numpy as np


browser = webdriver.Firefox()
browser.get(<URl with image>)

# Element to be saved
element = browser.find_element_by_id(<id of element>)

png = browser.get_screenshot_as_png()
location = element.location
size  = element.size

nparr = np.frombuffer(png, np.uint8)
img = cv2.imdecode(nparr, cv2.IMREAD_COLOR)


left = location['x']
top = location['y']
right = location['x'] + size['width']
bottom = location['y'] + size['height']

#im = img[left:right, top:bottom]
im = img[top:int(bottom), left:int(right)]
cv2.imwrite('filename.png',im)

【讨论】：