--- a/INDEX
+++ b/INDEX
@@ -110,6 +110,7 @@
  stdfilt
  entropyfilt
 Utilities
+ getrangefromclass
  iptnum2ordinal
  iptcheckstrs
  iptchecknargin

new file mode 100644
--- /dev/null
+++ b/inst/getrangefromclass.m
@@ -0,0 +1,68 @@
+## Copyright (C) 2011 Carnë Draug <carandraug+dev@gmail.com>
+##
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program; if not, see <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {@var{range} =} getrangefromclass (@var{img})
+## Return display range of image.
+##
+## For a given image @var{img}, returns @var{range}, a 1x2 matrix with the
+## minimum and maximum values. It supports the same classes as @code{intmax} and
+## @code{intmin}, as well as 'logical', 'single', and 'double'.
+##
+## For @sc{matlab} compatibility, if @var{img} is of the class 'single' or
+## 'double', min and max are considered 0 and 1 respectively.
+##
+## @example
+## @group
+## getrangefromclass (ones (5)) # note that class is 'double'
+##      @result{} [0   1]
+## getrangefromclass (logical (ones (5)))
+##      @result{} [0   1]
+## getrangefromclass (int8 (ones (5)))
+##      @result{} [-128  127]
+## @end group
+## @end example
+##
+## @seealso{intmin, intmax, bitmax}
+## @end deftypefn
+
+function r = getrangefromclass (img)
+
+  if (nargin != 1)
+    print_usage;
+  ## note that isnumeric would return false for logical matrix and ismatrix
+  ## returns true for strings
+  elseif (!ismatrix (img) || ischar (img))
+    error ("Argument 'img' must be an image");
+  endif
+
+  cl = class (img);
+  if (regexp (cl, "u?int(8|16|32|64)"))
+    r = [intmin(cl) intmax(cl)];
+  elseif (any (strcmp (cl, {"single", "double", "logical"})))
+    r = [0 1];
+  else
+    error ("Unknown class '%s'", cl)
+  endif
+
+endfunction
+
+%!assert (getrangefromclass (double (ones (5))) == [0 1]);      # double returns [0 1]
+%!assert (getrangefromclass (single (ones (5))) == [0 1]);      # single returns [0 1]
+%!assert (getrangefromclass (logical (ones (5))) == [0 1]);     # logical returns [0 1]
+%!assert (getrangefromclass (int8 (ones (5))) == [-128 127]);   # checks int
+%!assert (getrangefromclass (uint8 (ones (5))) == [0 255]);     # checks unit
+%!fail ("getrangefromclass ('string')");                        # fails with strings
+%!fail ("getrangefromclass ({3, 4})");                          # fails with cells