On Thu, Mar 29, 2012 at 4:12 PM, <boo...@nc.rr.com> wrote: > This message has two subjects. > 1. Is there a gaussian reduce operation in GEGL? Refer to the paper by Burt > and Adelson, 1983, where it is called REDUCE and apparently claims that it is > faster than operation gaussian blur followed by down-sample (scale by 1/2). > Used in the production of a gaussian pyramid. It seems to me to be a > fundamental operation and should be in GEGL. A search shows that the > operation mantiuk06 for GSOC might have generated gaussian pyramids but AFAIK > did not expose reduce() as a operation. There is also a corresponding > inverse operation EXPAND, which is useful in generating a Laplacian pyramid. > I have a use for a gaussian pyramid and might consider implementing gaussian > reduce for GEGL (instead of the naive approach of using gaussian blur > followed by scale.) The gaussian and laplacian pyramids are used in texture > synthesis and image compression.
There is no such op at the moment, but it does sound like something that would be a useful building block for other things. > 2. A few weeks ago I posted to GIMP-dev list about > https://github.com/bootchk/pluginGEGLpluginGIMP a GEGL operation that lets > you used GEGL in GIMP plugins written in Python and using Pygegl binding. > Its not in the form of a proper patch to GEGL but I would make a patch if I > thought it would help anyone to evaluate whether it should be part of GEGL. The proper migration of GIMP to GEGL has ramped up significantly the last month, in GIMP-2.10 the tile based drawable API will be marked as deprecated and the official way for plug-ins to interact with the GIMP core will be through GeglBuffers, for a very simple example see this file: http://git.gnome.org/browse/gimp/tree/plug-ins/common/goat-exercise.c?h=goat-invasion /Øyvind K. -- «The future is already here. It's just not very evenly distributed» -- William Gibson _______________________________________________ gegl-developer-list mailing list gegl-developer-list@gnome.org http://mail.gnome.org/mailman/listinfo/gegl-developer-list
