document the interleave option for reading raw images

diff --git a/Imager.pm b/Imager.pm
index 7ab5d2f9eda11571b4e758f300cc66765b4f73ca..cbbc090104cee0e5c9629576d5ec9992d8bf65d9 100644 (file)
--- a/Imager.pm
+++ b/Imager.pm
@@ -1509,6 +1509,15 @@ values for each pixel you could do:
             storechannels=>3)
     or die "Cannot read raw image\n";
 
             storechannels=>3)
     or die "Cannot read raw image\n";
 

+Normally the raw image is expected to have the value for channel 1
+immediately following channel 0 and channel 2 immediately following
+channel 1 for each pixel.  If your input image has all the channel 0
+values for the first line of the image, followed by all the channel 1
+values for the first line and so on, you can use the interleave option:
+
+  $img->read(file=>'foo.raw', xsize=100, ysize=>100, interleave=>1)
+    or die "Cannot read raw image\n";
+

 =head2 Multi-image files
 
 Currently just for gif files, you can create files that contain more
 =head2 Multi-image files
 
 Currently just for gif files, you can create files that contain more