## Copyright (C) 1996, 1997 John W. Eaton
##
## This file is part of Octave.
##
## Octave 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 2, or (at your option)
## any later version.
##
## Octave 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 Octave; see the file COPYING.  If not, write to the Free
## Software Foundation, 59 Temple Place - Suite 330, Boston, MA
## 02111-1307, USA.

## Image format conversion

## Author: Tony Richardson <amr@mpl.ucsd.edu>
## Created: July 1994
## Adapted-By: jwe

function [X, map] = gray2ind (I, n)

  if (nargin < 1 || nargin > 2)
    usage ("gray2ind (I, n)");
  elseif (nargin == 1)
    n = 64;
  endif

  map = gray (n);

  X = round (I*(n-1)) + 1;

endfunction