anchor.diff:  	       (setf term (decode-scan image j s)))))
   
   (defun decode-stream (stream &key buffer (colorspace-conversion t))
  -  "Return image array, height, width, and number of components. Does not support
  +  "Return image array, height, width, number of components and APP14 Adobe transform. Does not support
   progressive DCT-based JPEGs."
     (unless (= (read-marker stream) +M_SOI+)
       (error 'unrecognized-file-format))
  
positive.code:                (= +M_SOF2+ marker)) (decode-frame-beginning image stream nil)
             (values (descriptor-height image)
                     (descriptor-width image)
  		   (descriptor-ncomp image)))
            (t (error 'unsupported-jpeg-format :code marker)))))
  
  (defun jpeg-file-dimensions (filename)
    "Return image height, width and number of components"
    (with-open-file (in filename :direction :input :element-type 'uint8)
      (decode-stream-height-width-ncomp in)))
  
negative.code:            (values (descriptor-buffer image)
                     (descriptor-height image)
                     (descriptor-width image)
                     (descriptor-ncomp image)
  		   (descriptor-adobe-app14-transform image)))
            (t (error 'unsupported-jpeg-format :code marker)))))
  
  ;;; Top level decoder function
  