Saving screen-shot of tkinter window as image

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Discussion Overview

The discussion revolves around capturing and saving screenshots of a tkinter window as an image. Participants explore different methods and address issues related to image alignment and dimensions.

Discussion Character

  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant shares a code snippet using PIL and win32gui to capture a tkinter window and save it as a PNG file.
  • Another participant questions the alignment of the saved image, asking whether the issue is horizontal, vertical, or both.
  • A participant confirms that the saved image is off-center both horizontally and vertically, and mentions a partial resolution using pyscreenshot.grab while adjusting capture dimensions manually.
  • Another participant suggests that the screenshot might include more than just the intended window, referencing documentation about the behavior of PIL.ImageGrab.grab regarding bounding boxes and screen captures.

Areas of Agreement / Disagreement

Participants express differing views on the effectiveness of the methods used for capturing the tkinter window, and there is no consensus on the best approach to resolve the alignment issues.

Contextual Notes

Participants note limitations related to the bounding box used in screenshots and the potential inclusion of additional screen elements in the captured image.

Eclair_de_XII
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TL;DR
Using PIL and win32gui in order to capture tkinter window as image, then save to file. It's always off-center, and I haven't a clue why.
[CODE lang="python" highlight="26,27,28,33"]from PIL import ImageGrab
from win32gui import GetWindowRect

def find_img_loc():
k=1
folder=sep.join((getcwd(),'screenshots'))
initial_file='screenshot'+str(k)
filename=lambda x: sep.join((folder,x+'.png'))
while exists(filename(initial_file)):
k+=1
n=len(str(k-1))
initial_file=initial_file[:-n]+str(k)
kw={
'initialfile':initial_file,\
'defaultextension':'png',\
'initialdir':folder,\
'filetypes':[('.png files only','*.png')]
}
filename=filedialog.asksaveasfilename(**kw)
return filename

def save_image(root):
if not exists('screenshots'):
mkdir('screenshots')
root.update()
HWND = root.winfo_id() # get the handle of the canvas
rect = GetWindowRect(HWND) # get the coordinate of the canvas
I am = ImageGrab.grab(rect) # get image of the current location
filename=find_img_loc()
if not filename:
return
else:
im.save(filename,format='png')

if __name__ == '__main__':
root=Tk()
lines='Sample text here','More sample text...','One more for the road.'
for n, text in enumerate(lines):
Label(root,text=text).grid(row=n)
save_image(root)
root.destroy()[/CODE]

This code was actually from:

https://stackoverflow.com/questions/9886274/how-can-i-convert-canvas-content-to-an-image
 
Last edited:
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how is it off center? horizontally or vertically or both?
 
It was both.

The actual window looks like this:

actual.png
but the saved image looks like this:
screenshot4.png
In any case, I resolved the issue (partially) by using pyscreenshot.grab and manually tinkering with the capture dimensions. It was not efficient, I confess, but it did the trick alright

Python: 
from os import mkdir, getcwd
from os.path import exists, sep

from pyscreenshot import grab

def find_img_loc():
    k=1
    folder=sep.join((getcwd(),'screenshots'))
    initial_file='screenshot'+str(k)
    filename=lambda x: sep.join((folder,x+'.png'))
    while exists(filename(initial_file)):
        k+=1
        n=len(str(k-1))
        initial_file=initial_file[:-n]+str(k)
    kw={
        'initialfile':initial_file,\
        'defaultextension':'png',\
        'initialdir':folder,\
        'filetypes':[('.png files only','*.png')]
        }
    filename=filedialog.asksaveasfilename(**kw)
    return filename

def save_image(im):
    if not exists('screenshots'):
        mkdir('screenshots')
    filename=find_img_loc()
    if not filename:
        return
    else:
        im.save(filename,format='png')

def save_image2(root):
    root.update()
    geometry=root.winfo_geometry()
    position=geometry.split('+')
    dimension=position[0].split('x')
    xlen=dimension[0]
    ylen=dimension[1]
    xpos=position[1]
    ypos=position[2]
    geo_list=(xpos,ypos,xlen,ylen)
    geometry=()
    k=1.25
    for n,g in enumerate(geo_list):
        g=int(g)
        g=k*g
        if n == 0:
            g+=10
        g=int(g)
        if n>1:
            h=geo_list[n-2]
            h=int(h)
            h=k*h
            k*=1.075
            h=int(h)
            geometry+=(g+h,)
        else:
            geometry+=(g,)
    im=grab(bbox=geometry)
    save_image(im)

if __name__ == '__main__':
    root=Tk()
    root.geometry('400x400+400+100')
    Label(root,text='Yabba dabba doo').grid()
    save_image1(root)
 
Could it be that the screenshot you captured included more than just that one text window? If you manually capture a screenshot of that window, and then paste it into, say, Paint or other graphics app, do you get just that single window or do you get more?

Some documentation I found here says this. Note the last sentence.
PIL.ImageGrab.grab(bbox=None, include_layered_windows=False, all_screens=False, xdisplay=None)
Take a snapshot of the screen. The pixels inside the bounding box are returned as an “RGBA” on macOS, or an “RGB” image otherwise. If the bounding box is omitted, the entire screen is copied.