Mercurial > hg > octave-image

changeset 606:20f20769cd9f

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
rgb2gray: use isimage and iscolormap function
author carandraug
date Mon, 24 Sep 2012 14:57:19 +0000
parents 764d78294156
children dde719c94995
files inst/rgb2gray.m
diffstat 1 files changed, 5 insertions(+), 6 deletions(-) [+]
line wrap: on
line diff
--- a/inst/rgb2gray.m
+++ b/inst/rgb2gray.m
@@ -15,8 +15,7 @@
 
 ## -*- texinfo -*-
 ## @deftypefn {Function File} @var{gray}= rgb2gray (@var{rgb})
-## Converts an RGB image to a gray scale image, or a color map
-## to a gray map.
+## Convert RGB image or colormap to a grayscale.
 ##
 ## If the input is an RGB image, the conversion to a gray image
 ## is computed as the mean value of the color channels.
@@ -32,10 +31,10 @@
     print_usage();
   endif
 
-  if (ismatrix (rgb) && ndims(rgb) == 2 && columns(rgb) == 3)
+  if (iscolormap (rgb))
     ntscmap = rgb2ntsc (rgb);
-    gray = ntscmap (:, 1) * ones (1, 3);
-  elseif (ismatrix(rgb) && ndims(rgb) == 3)
+    gray    = ntscmap (:, 1) * ones (1, 3);
+  elseif (isimage (rgb) && ndims(rgb) == 3)
     switch(class(rgb))
     case "double"
       gray = mean(rgb,3);
@@ -47,6 +46,6 @@
       error("rgb2gray: unsupported class %s", class(rgb));
     endswitch
   else
-    error("rgb2gray: the input must either be an RGB image or a color map");
+    error("rgb2gray: the input must either be an RGB image or a colormap");
   endif
 endfunction