Original and a greyscale from CIE luminance

8x magnification - greyscale

DDT method (8 passes using yms optimisation)

8x magnification - colour

DDT method (8 passes using yms optimisation)

DDT method (3 passes using yms optimisation)

Photo from a recent shuttle mission

zoomed section original

4x magnification using gimp

DDT method (8 passes using yms optimisation

A simple example

Original

My implementation

Gimp version

Another edge-directed algorithm on the same image

 Name                    Last modified      Size  Description
 Parent Directory                             -   
 t/                      30-Mar-2010 20:10    -   
 truck-distance-8pass..> 11-Jun-2002 07:13  340   
 truck-yms-8pass.txt     11-Jun-2002 07:13  340   
 truck-distance-8pass..> 11-Jun-2002 07:13  681   
 costfunc.png            30-May-2002 21:10  3.4K  
 flowerg.png             09-Jun-2002 21:35  8.9K  
 lisa-scale12.png        08-Jun-2002 14:48   19K  
 lisa.png                08-Jun-2002 12:14   34K  
 imagefilt-rob.tar.gz    06-Jan-2003 13:57   37K  
 flowerg-gimp.png        25-Jun-2002 21:53   50K  
 flow.png                09-Jun-2002 21:35   53K  
 lisa-scale4.png         08-Jun-2002 12:13   62K  
 truck.png               11-Jun-2002 07:30  224K  
 s110-zoom.png           08-Jun-2002 15:50  247K  
 thigh2.png              12-Jun-2002 11:40  284K  
 thigh.png               12-Jun-2002 11:39  306K  
 lisa-gimp8.png          08-Jun-2002 14:51  310K  
 lisa-scale14.png        08-Jun-2002 15:16  349K  
 lisa-scale7.png         08-Jun-2002 13:03  398K  
 lisa-scale5.png         08-Jun-2002 12:14  415K  
 lisa-gimp8c.png         08-Jun-2002 14:32  710K  
 lisa-scale10.png        08-Jun-2002 14:32  762K  
 lisa-scale11.png        08-Jun-2002 14:46  763K  
 s110e5004.jpg           08-Jun-2002 15:52  1.4M  
 s110-zoom-gimp4.png     08-Jun-2002 15:50  1.8M  
 s110-zoom-ddt.png       08-Jun-2002 15:48  2.1M