MESSAGE
| DATE | 2008-09-15 |
| FROM | Ruben Safir
|
| SUBJECT | Subject: [NYLXS - HANGOUT] Gimp Filters
|
Linux.com
Everything Linux and Open Source
GIMP User Filter allows use of Photoshop filters
September 15, 2008 (7:00:00 PM) - 9 hours, 29 minutes ago
By: Bruce Byfield
One brake on the GIMP's popularity is that, while it boasts dozens of
filters, a rival like Photoshop boasts thousands. You may only
occasionally need a special effect that imitates a pencil sketch or a
famous style of painting such as Impressionism or Cubism, but, when you
do, having a filter to create the effect instantly saves serious amount
of time. To help bridge this divide, the GIMP is reviving the User
Filter from its 1.x releases. This filter is a kind of meta-plugin that
allows users to import and manage Photoship filters or, if they have the
knowledge, to write their own.
The GIMP User Filter is available from the project's SourceForge.net
site as source code or as a Debian package that may or may not work on
Ubuntu, to judge from mailing list chatter. Once you install it, you
will find it under Filter - > Generic -> User Filter.
You can find links to Photoshop filters through the portal site
Photoshop Filters.com. The most useful links on the site are Filter
Factory, the largest filter repository for Photoshop, and The Filters, a
list of other filter collections. Before you start User Filter, you'll
want to download some of these filters, unzipping them if necessary.
Since these filters are not written by the free software community, they
are often not licensed, but, since they are available for download, you
can generally assume that they are public domain or shareware,
particularly if you are using them privately. Professional designers,
however, might want to check for licenses more carefully.
Working with User Filter
If you have never worked with GIMP or Photoshop filters, your first
reaction to the User Filter window may be pure panic. The Filter
Interface and Filter Formula sections of the Filter Editor tab, as well
as the entire Filter Control tab, may seem like gibberish in which the
only sense you can see is that the number 255 refers to the top value in
RGB color values.
Fortunately, if your only interest is in importing filters, you can
ignore the controls for writing filters. To import a Photoshop filter,
all you need to do is click the Open button on the Filter Editor tab and
navigate to your download directory. By default, the file manager
displays only .GUF (native GIMP files), so you need to change it to .8bf
(Photoshop filters) or, better yet, since some of the downloaded filters
may not have case-sensitive names and display their extensions as
all-caps, to All files. When you have selected a filter, you can see a
preview in the top left of the screen. To apply it to the currently
active file in the GIMP, click the OK button.
Should you find the filter worth keeping, go to the Filter Directories
tab to designate a storage directory for imports. If you save the filter
with a .GUF extension, you can save time the next time you use the
filter by going directly to the Filter Manager tab, which lists only
imported filters.
Writing filters
So far, so simple. However, taking User Filter to the next level is
probably a giant leap for most users. Using a duplicate copy of a
filter, you can experiment with some of the controls, especially ones
that change RGB color values, but you are unlikely to go farther without
detailed understanding of how a filter is constructed.
Since User Filter does not come with help yet, you will need to find
other sources to learn from. One starting point should be the Filters
section of the online GIMP help site, followed the Scripting section,
which may help you understand what you are dealing with. For more
detailed information, try the Filter Factory Programming Guide and the
GIMP Talk forum for plugins, filters, and scripts, and to ask specific
questions. However, you will probably need to be more highly motivated
than most people to master writing your own filter, since User Filter
clearly assumes that you are already familiar with the process.
For most of us, User Filter's main utility will probably remain as a
filter importer. Not all Photoshop filters import cleanly -- only about
80%, to judge from my more or less random experiments. Still, even that
is a huge improvement in the number of filters compared to what comes
bundled with the GIMP. It's enough, anyway, to help you shake the
suspicion that, by not actually writing your own filters, you're doing
the graphics editor equivalent of using a professional publishing
package to compose your grocery list.
Read in the original layout at: http://www.linux.com/feature/147173
--
http://www.mrbrklyn.com - Interesting Stuff
http://www.nylxs.com - Leadership Development in Free Software
So many immigrant groups have swept through our town that Brooklyn, like Atlantis, reaches mythological proportions in the mind of the world - RI Safir 1998
http://fairuse.nylxs.com DRM is THEFT - We are the STAKEHOLDERS - RI Safir 2002
"Yeah - I write Free Software...so SUE ME"
"The tremendous problem we face is that we are becoming sharecroppers to our own cultural heritage -- we need the ability to participate in our own society."
"> I'm an engineer. I choose the best tool for the job, politics be damned.<
You must be a stupid engineer then, because politcs and technology have been attached at the hip since the 1st dynasty in Ancient Egypt. I guess you missed that one."
© Copyright for the Digital Millennium
|
|
