Can python get the screen shot of a specific window?

Question

For example, I am running a java program. Can I use python to get the content(screenshot) of this java program? Not the full screen, just the java program.

I have seen this module, but it required a parameter of "where the program window is":

import pyscreenshot as ImageGrab

if __name__ == "__main__":
    # part of the screen
    im=ImageGrab.grab(bbox=(10,10,510,510)) # X1,Y1,X2,Y2
    im.show()
#-#

But this may not be what I am seeking since it requires the bounding_box.

Answer 1

There are multiple ways to do that. The code for these will require modification based on your needs, so I will put in some pointers to the high level methods and libraries:

1. You can directly use GUI-automation tools such as Pyautogui to press Alt+PrntScreen and transfer the data from clipboard into a variable (http://pyautogui.readthedocs.io/en/latest/keyboard.html#keyboard-keys)

2. You can use pywin32 and PIL to grab the image of a certain window (How to Get a Window or Fullscreen Screenshot in Python 3k? (without PIL))

3. You can use imagemagik to grab screenshots of a single window (https://www.imagemagick.org/discourse-server/viewtopic.php?t=24702)

4. You can use Pyautogui.locateOnScreen(“Sceenshot.PNG”) to find the tuple which will contain the boundaries of the window for your java app. Then you can pass it to your functionimg.ImageGrab.grab(bbox)`

Answer 2

A example to get the content(screenshot) of a specific window with the help of the pygetwindow module.

import pygetwindow
import time
import os
import pyautogui
import PIL

# get screensize
x,y = pyautogui.size()
print(f"width={x}\theight={y}")

x2,y2 = pyautogui.size()
x2,y2=int(str(x2)),int(str(y2))
print(x2//2)
print(y2//2)

# find new window title
z1 = pygetwindow.getAllTitles()
time.sleep(1)
print(len(z1))
# test with pictures folder
os.startfile("C:\\Users\\yourname\\Pictures")
time.sleep(1)
z2 = pygetwindow.getAllTitles()
print(len(z2))
time.sleep(1)
z3 = [x for x in z2 if x not in z1]
z3 = ''.join(z3)
time.sleep(3)

# also able to edit z3 to specified window-title string like: "Sublime Text (UNREGISTERED)"
my = pygetwindow.getWindowsWithTitle(z3)[0]
# quarter of screen screensize
x3 = x2 // 2
y3 = y2 // 2
my.resizeTo(x3,y3)
# top-left
my.moveTo(0, 0)
time.sleep(3)
my.activate()
time.sleep(1)

# save screenshot
p = pyautogui.screenshot()
p.save(r'C:\\Users\\yourname\\Pictures\\\\p.png')

# edit screenshot
im = PIL.Image.open('C:\\Users\\yourname\\Pictures\\p.png')
im_crop = im.crop((0, 0, x3, y3))
im_crop.save('C:\\Users\\yourname\\Pictures\\p.jpg', quality=100)

# close window
time.sleep(1)
my.close()