Selective color-based blur
(actual version 0.3.5 - less-more stable, 0.3.8 development version)

is gimp plugin that blurs the color information (both hue and saturation) in image. 


==PURPOSE==

There are two basic usages:

1.) for poorly saturated images - blur color and saturate it afterwards. This way
you should avoid artifacts that can happen during saturation
2.) Alternatively you can use it for creating of cartoon like images.


==HOW IT WORKS AND USE MINIGUIDE:==

The plugin works in iterations and with each iteration it tests n (n=radius) pixels in eight directions - up, right, down, left and diagonally between them.
If color  distance of all n pixels to central pixel is below the treshold (in normalized RGB colorspace, i.e. brightness is ignored) then those pixels
are considered for blurring. So final values are calculated as average from averages of up to 8 lines of pixels. (Perhaps some graphical explanation
would be usefull here.)
Since about 0.2.2 you can set up also brightness treshold, seems to be very usefull option as well.

User defines five basic parameters:
RADIUS -  distance in 8 directions from central pixel. The single direction (set of RADIUS pixels) is either accepted or rejected as an entity.
ITERATIONS - how many times the procedure described above is repeated. 
(I can say that RADIUS * ITERATIONS = overall radius of blurring)
COLOR TRESHOLD - should be obvious
VALUE (BRIGHTNESS) TRESHOLD - should be obvious as well just keep in mind that brightness is converted to values 0 - 1.
LINESENSITIVITY - this controls how many pixels will be made black (~become lines)

And there is a combobox with 4 options:
Preserve brightness - blur colors on place (fastes way, consider saturation boost checkbutton here)
Cartoonize with reduced range of brightness
Cartoonize - should be self explanatory
Create lines - related to previous option

1 checkbutton
CLEAN SMALL NOISE / Force smoothing - selfexplanatory (name and algorithm changed in 0.3.6)

EXPORT TO NEW LAYER is available as well


NON-INTERACTIVE mode added in 0.3.5 (see attached Readme-NON-INT.txt for more info)

==INSTALLATION:==

On LINUX:
optional:
  export LDFLAGS="$LDFLAGS -lm"
for user:
  gimptool-2.0 --install colorblur.c
and for system-wide installation:
  gimptool-2.0 --install-admin colorblur.c

For WINDOWS and others:
I'm not able to compile it for windows, but visit this page and search within the discussion: http://registry.gimp.org/node/25801

TO BE FOUND at: FILTERS -> BLUR -> COLOR SELECTIVE BLUR


==ISSUES & SHORTCOMINGS ==

Compilation might show this:
   colorblur.c:551:4: warning: ‘g_thread_create’ is deprecated (declared at /usr/include/glib-2.0/glib/deprecated/gthread.h:100): Use 'g_thread_new' instead [-Wdeprecated-declarations]
I will fix it later :)


==CONTACT AND FURTHER INFO==

The plugin is multithreaded (5 threads, can be changed in the source)

For more info you can visit: http://code.google.com/p/selective-color-blur/wiki/Introduction

For some other info, to discuss and for windows packages visit: http://registry.gimp.org/node/25801

email: tiborb95 at gmail dot com, any feedback welcomed


Last update: 16. Jan 2013

