anchor.diff:  		       (xlib:put-image pixmap pixmap-gc image :width width :height height :x 0 :y 0)
   		       (xlib:copy-area pixmap gc 0 0 width height window 0 0)
   		       (xlib:display-force-output display)
  -		       (unless (pause avi)
  +		       (unless (pause container)
   			 (bt:acquire-lock (vacancy-lock (car (rcursor rec))))
   			 (bt:release-lock (vacancy-lock cur)))
   		       (when (eql cur (final rec))
  
positive.code: 					    display
  					    (xlib:keycode->keysym display code 0))
  				       (#\q
  					(setf (finish avi) t)
  					(setf quit t))
  				       ((#\Space #\p)
  					(setf (pause avi) (not (pause avi)))
  					(bt:acquire-lock (pause-lock avi))
  					(bt:release-lock (pause-lock avi))))
  				     t))))
  	     (stream-playback-stop rec)
  	     (xlib:free-pixmap pixmap)
  
negative.code: 		(buffer (make-array `(,height ,width) :element-type 'xlib:pixel))
  		(image (xlib:create-image  :data buffer :depth 24
  					   :height height :width width))
  		(rec (find-video-stream-record container)))
  	   (unwind-protect
  		(progn
  		  (setf (xlib:wm-name window) (pathname-name (filename container)))
  		  (xlib:map-window window)
  		  (stream-playback-start rec)
  		  (loop with quit = nil until quit
  		     for cur = (if (pause container) cur (pop (rcursor rec)))
  		     for src = (frame cur) do
  		       (loop for i from 0 below height do
  			    (loop for j from 0 below width
  