pywinauto capture_as_image adds unwanted borders

Question

I am using pywinauto to take a screenshot of a specific window.

Here is the code I use to take a capture of notepad ("Bloc-notes" in french) :

from pywinauto import Application
app = Application().connect(title_re=".*Bloc-notes")
hwin = app.top_window()
hwin.set_focus()
img = hwin.capture_as_image()
img.save('notepad_screenshot.png')

And here is the result:

The red "border" is the background of the window. How can I safely eliminate this red border?

I tried to configure Windows 10 in order not to show windows shadows (in the "visual effects settings") but it has no effect on the size of the capture.

When I look precisely on the capture, I can see that the left, bottom and right borders are 7 pixels thick. Can I reliably remove these pixels? What I mean by "reliably" is: will it always work, and work on other computers?

Any help appreciated.

While trying to find a solution, I found the following post giving a solution in VB: https://stackoverflow.com/a/34143777/3909303 — Simpom, Feb 19 '19 at 15:42

score 3 · Accepted Answer · answered Feb 19 '19 at 16:33

3

Here is the solution I found.

import ctypes
from pywinauto import Application
import win32gui

app = Application().connect(title_re=".*Bloc-notes")
hwin = app.top_window()
hwin.set_focus()

window_title = hwin.window_text()
rect = ctypes.wintypes.RECT()
DWMWA_EXTENDED_FRAME_BOUNDS = 9
ctypes.windll.dwmapi.DwmGetWindowAttribute(
    ctypes.wintypes.HWND(win32gui.FindWindow(None, window_title)),
    ctypes.wintypes.DWORD(DWMWA_EXTENDED_FRAME_BOUNDS),
    ctypes.byref(rect),
    ctypes.sizeof(rect)
)

img = hwin.capture_as_image(rect)
img.save('notepad_screenshot_ok.png')

And here is the result:

It has worked on all the tests I run (different windows).

answered Feb 19 '19 at 16:33

Simpom

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Glad to see it will help the development of pywinauto! – Simpom Feb 20 '19 at 08:19
BTW, you can accept your own answer. It seems correct. – Vasily Ryabov Feb 20 '19 at 12:31
I got an 'RECT' object has no attribute 'width' error – Louie Lee Jan 01 '20 at 05:45
What instruction is raising the exception, precisely? ctypes.sizeof(rect)? – Simpom Jan 01 '20 at 08:10
No, exactly this code is failing. I confirm. `pywinauto.win32structures.RECT` can be used for now as a workaround. – Vasily Ryabov Jan 01 '20 at 17:14
What does that mean? Has the ctypes.wintypes changed, breaking backward compatibility? – Simpom Jan 02 '20 at 21:50
yeah `width()` and `heigh()` methods are missing on `ctypes.wintypes.RECT`. added an hackish fix. – Brucie Alpha Nov 12 '20 at 20:27

score 0 · Answer 2 · edited Jul 09 '20 at 05:39

0

Application().connect can return a collection of windows.

Instead use app['YOUR TITLE HERE'] or use find_windows.

From there you can capture the image without those borders.

You can find more info from the docs.

edited Jul 09 '20 at 05:39

סטנלי גרונן

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answered Jul 09 '20 at 05:19

Joseph Luce

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pywinauto capture_as_image adds unwanted borders

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