Screencap monitor selection parameter

CharlieScene · 2 March 2024 06:26

Hi everyone,

I have a small issue with ScreenCap library, linked to the monitor parameter
I simply use :

Take Partial Screenshot    name=screen quality=100    left=25    top=450    width=1750    height=300    monitor=0

But on my two screens setup, no matter the monitor value is (0, 1, 2…) the left screen is always captured.
Worse for some values (i.e. 1) screenshot is performed, but with a smaller size/ratio.

I’m maybe missing something…
Additional infos is that my top TEST_SETUP has a mechanism to Start Video Recording and here the monitor parameter works.
Only difference is that parameter is set in Library importing part.
On the test case issue I have not ScreenCap import and the keyword is functioning.

Thanks for your hints.

Charlie

damies13 · 6 March 2024 04:38

Hi Charlie,

I had a little free time, so did some digging, I think the problem is here

github.com

rticau/ScreenCapLibrary/blob/146304edac5a062a39f6c738a0516212acbd0197/src/ScreenCapLibrary/client.py#L148


      
              return _take_gtk_screenshot(path, format, quality, monitor)
          
          def _take_screenshot_client_mss(self, name, format, quality, monitor):
              if format in ['jpg', 'jpeg', 'webp']:
                  with mss() as sct:
                      sct_img = sct.grab(sct.monitors[int(monitor)])
                      img = Image.frombytes('RGB', sct_img.size, sct_img.bgra, 'raw', 'BGRX')
                      path = self._save_screenshot_path(name, format)
                      img.save(path, quality=quality if format == 'webp' else _pil_quality_conversion(quality))
                  return path
              elif format == 'png':
                  with mss() as sct:
                      path_name = self._save_screenshot_path(name, format)
                      sct.compression_level = _compression_value_conversion(quality)
                      path = sct.shot(mon=-1, output='%s' % path_name)
                  return path
              else:
                  raise RuntimeError("Invalid screenshot format.")
          
          def take_multiple_screenshots(self, name, format, quality, screenshot_number, delay_time, monitor):
              del self.frames[:]

I started from here:

github.com

rticau/ScreenCapLibrary/blob/146304edac5a062a39f6c738a0516212acbd0197/src/ScreenCapLibrary/client.py#L200


      
          def _take_multiple_screenshots_gtk(self, delay, shot_number, monitor):
              taken = 0
              width, height = _take_gtk_screen_size(monitor)
              while taken < shot_number:
                  pb = _grab_gtk_pb(monitor)
                  img = Image.frombuffer('RGB', (width, height), pb.get_pixels(), 'raw', 'RGB')
                  self.frames.append(img)
                  time.sleep(timestr_to_secs(delay))
                  taken += 1
          
          def take_partial_screenshot(self, name, format, quality,
                                      left, top, width, height, embed, embed_width, monitor, save_to_disk):
              left = int(left)
              top = int(top)
              width = int(width)
              height = int(height)
              format = (format or self._format).lower()
              quality = quality or self._quality
          
              if is_pygtk(self.screenshot_module):
                  format = 'jpeg' if format == 'jpg' else format

and followed the code paths to endup at the point above.

If I understood correctly if is_pygtk is false (I think this means windows) and you are taking a png screenshot then the monitor variable is not used and it looks like it doesn’t even do the partial screenshot

Can you try using a jpeg screenshot and confirm my suspicion?

Dave.

CharlieScene · 6 March 2024 20:00

Hi Dave,

Thanks for the digging.
Indeed it seems that some part are not used in my case…
I don’t have the setup right now being on the move. But I’ll give it a try and let you know.
Thanks !

Charlie

damies13 · 8 March 2024 07:14

Hi Charlie,

If you find I’m right, the best thing to do is log a issue in the Library’s issue register, as I’m not involved in that library.

Dave.

CharlieScene · 12 March 2024 19:08

Hi Dave,

Made tests just now, setting the format=jpeg in the Take Partial Screenshot keyword works properly.
It takes screenshot with monitor 1 or 2 as settled also in the keyword.
Value 0 should do both screens, but on a partial screenshot not sure about expected behavior.

Anyway I’ve opened an issue on the library, see if something can be done.
The concerned tests are runned in Docker so it’s not a big issue, but when debugging or else outside of the container this can be cumbersome.

Thanks again for the help !

Charlie

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Screencap monitor selection parameter

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