anchor.diff:  		  (xlib:event-case (display :discard-p t)
   		    (exposure ()
   			      (loop for i from 0 below height
  -				 with src = (frame (pop (rcursor rec))) do
  +				 with src = (frame (pop-chunk rec)) do
   				   (loop for j from 0 below width
   				      for spos = (* 3 (+ j (* width i))) do
   					(setf (aref buffer i j)
  
positive.code: 		(buffer (make-array `(,height ,width) :element-type 'xlib:pixel))
  		(image (xlib:create-image  :data buffer :depth 24
  					   :height height :width width))
  		(rec (find-if #'(lambda (x) (eql (type-of x) 'mjpeg-stream-record)) stream-records)))
  	   (unwind-protect
  		(progn
  		  (setf (xlib:wm-name window) (pathname-name (filename avi)))
  
negative.code: (defmethod play-stream ((avi avi-mjpeg-stream))
    (bt:make-thread 
     #'(lambda ()
         (with-slots (height width) avi
  	 (let* ((display (xlib:open-default-display))
  		(window (xlib:create-window :parent (xlib:screen-root (xlib:display-default-screen display))
  					    :x 0 :y 0 :width width :height height
  