anchor.diff:  ;;;
   ;;; FIXME! Writing indexed tiff images is broken!
   (defun write-tiff-stream (stream image &key byte-order)
  -  (declare (optimize (debug 3)))
     (let ((*byte-order* (or byte-order *byte-order*))
           (*tiff-file-offset* 0))
       ;; FIXME! The typecase below is a hack to get around the fact that
  
positive.code:     ;; here in order to keep opticl happy. I think we need two
      ;; write-tiff-{file,stream} flavors, one for opticl-core:image and
      ;; one for tiff-image.
      (let ((obj (make-tiff-image (typecase
                                      image
                                    (opticl-core:image image)
                                    (t (tiff-image-data image))))))
        (multiple-value-bind (fields out-of-line-data-size strip-offsets strip-byte-counts)
            (make-tiff-fields obj)
          (write-value 'tiff-fields stream fields)
  
negative.code:     (read-tiff-stream stream)))
  
  
  (defun make-tiff-image-for-output (image)
    (typecase image
  
      (16-bit-gray-image
  