I would like to monitor what's displayed on my screen. For exemple suppose I want to make my screen wobbly (trembling like hell). THen my idea is to access the data about pixels that are supposed to be displayed, then modify their coordinates, then sending them back to the display image queue. Perhaps it's not working that way at all, I don't know? Any insight would be appreciated!
A part of normally working display window can be captured by
scrot -s SCR_IMG.png, clicking and draggging the mouse to surround a desired part of the display by a rectangle. The
SCR_IMG.pngfile then contains the captured part.