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How to choose which screen ImageGrab.grab () captures in setting up multiple monitors?

As in the title, I wonder if there is a way to configure the ImageGrab.grab () module to capture, for example, the right screen, and not the left one in the setting with multiple monitors.

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Unfortunately, this is not possible because of how the PIL gets the dimensions of the display device. When it receives the device context, it receives one for all connected monitors:

screen = CreateDC("DISPLAY", NULL, NULL, NULL);

( display.c , line 296, version 1.1.7)

However, to get the dimensions of the display, it uses this code:

 width = GetDeviceCaps(screen, HORZRES); height = GetDeviceCaps(screen, VERTRES);

( display.c , lines 299-300, version 1.1.7)

Returns only the dimensions of the main, active monitor. All subsequent operations are performed with these widths and heights, resulting in a final image that is only the size of the main display.

To get a pop-up window of all connected monitors, these two lines must be replaced with something like:

 width = GetSystemMetrics(SM_CXVIRTUALSCREEN); height = GetSystemMetrics(SM_CYVIRTUALSCREEN);

After that, you will need to recompile the PIL. This will give you the dimensions of the virtual screen, which is the "... bounding box of all display monitors." [ MSDN ]

A more correct implementation would be to use EnumDisplayMonitors to obtain device contexts for individual monitors, as well as change the ImageGrab.grab () interface (or add a new function) to allow the selection of a specific monitor whose device context will be used for other operations.

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Source: https://habr.com/ru/post/907893/

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