--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/scripts/image/ind2gray.m	Mon Jul 25 22:19:05 1994 +0000
@@ -0,0 +1,35 @@
+function Y = ind2gray(X,map)
+#Convert an octave indexed image to a gray scale intensity image.
+#
+#Y = ind2gray(X) converts an indexed image to a gray scale intensity
+#image.  The current colormap is used to determine the intensities.
+#The intensity values lie between 0 and 1 inclusive.
+#
+#Y = ind2gray(X,map) uses the specified colormap instead of the current
+#one in the conversion process.
+#
+#SEE ALSO: gray2ind, rgb2ntsc, image, colormap
+
+  if (nargin == 1)
+    map = colormap;
+  endif
+
+  # Convert colormap to intensity values.
+  yiq = rgb2ntsc(map);
+  y = yiq(:,1);
+
+  # We need Fortran indexing capability, but be sure to save the user's
+  # preference.
+  pref = do_fortran_indexing;
+  do_fortran_indexing = "true";
+
+  # Replace indices in the input matrix with indexed values in the output
+  # matrix.
+  [rows, cols] = size(X);
+  Y = y(X(:));
+  Y = reshape(Y,rows,cols);
+
+  # Restore the user's preference.
+  do_fortran_indexing = pref;
+
+endfunction