generate

Render Technological Image

FyerEgg — Thu, 05 Nov 2009 17:15:52 +0100

Based on the set edge, pixel ammount, color and brightness, this script-fu generates a layer that looks techno.

Here is an example of what it makes...

You can find it when you create the image window...
Script-Fu -> Render -> Tech

(Note: This is my first Script-Fu)

Website Window Creator Script

dln385 — Fri, 27 Mar 2009 21:21:05 +0100

This script creates a new image with a window useful for web design.

To install this script, copy it to your scripts folder, then restart Gimp. If you don't know where your scripts folder is, then go to Edit > Preferences > Folders > Scripts.

To run this script, select File > Create > Website Window.

Feedback is appreciated, and I will consider any changes that you request.

gimp-netpbm2gimp-plugins and Netpbm2Gimp

pakin — Sat, 28 Feb 2009 04:01:55 +0100

gimp-netpbm2gimp-plugins is a collection of over 200 GIMP plug-ins produced by running the source code of the Netpbm graphics filters through Netpbm2Gimp, which is described below. (Note: Think "GIMP" where the Netpbm graphics filter documentation says "PBM", "PGM", "PPM", "PNM", or "PAM".) There is a particular emphasis on load/save plug-ins for obscure graphics formats, but a number of miscellaneous and useful image filters and image generators are included as well.

Netpbm2Gimp is a tool for programmers that converts programs written using the easy-to-use Netpbm library into GIMP plug-ins. Netpbm2Gimp reimplements the Netpbm functions in terms of GIMP/GTK+ functions, thereby hiding much of the complexity of plug-in development. With Netpbm2Gimp, plug-in developers needn't worry about registering plug-ins with the GIMP core, displaying dialog boxes to request input from the user, displaying dialog boxes to present the user with status or error information, handling noninteractive usage (for the GIMP scripting interfaces), managing various GIMP data structures (images, layers, drawables, shadow buffers, the tile cache, etc.), updating the progress bar, controlling the undo stack, and performing the various other operations that are needed in the context of a graphical user interface. All of those features are handled automatically by Netpbm2Gimp.

The source code and Linux binaries for both Netpbm2Gimp and gimp-netpbm2gimp-plugins are available from the Netpbm2Gimp home page, http://netpbm2gimp.sourceforge.net/.

Noise generator

marcor — Mon, 22 Dec 2008 19:13:22 +0100

This filter generates noise in an image. Available noise types are

Poisson noise
Gaussian noise
Uniform noise
Laplace noise
Lorentz noise

It is possible to generate (YCbCr) luminance noise only and to apply a gamma correction.

General description

for Poisson noise: the amount of photons per pixel value.
for Gaussian noise: the standard deviation of the noise distribution.
for uniform noise: the width of the uniform distribution.
for Laplace noise: the scale parameter.
for Lorentz noise: the half width half maximum (HWHM).

For all noise types together you can select whether a gamma correction should be applied on the image such that noise is applied to linear image data. After noise application the image is retransformed to sRGB. You can also select whether or not you want to have luminance noise only and for that the image is transformed to the YCbCr colour space before adding noise.

Noise types

Here the different noise types are described. The histogram of each noise type is a real application of the filter on a neutal gray image (128).

Poisson noise

A source for Poisson noise is photon counting. When taking a picture in the real world photons (light particles) arrive at a certain rate. However photons are not correlated and thus the time between photons is not always the same. Therefore given the shutter time of your camera and a photon rate you may collect more or less photons in subsequent pictures. The number of photons you actually collect is Poisson distributed.

Calculating poisson distributed random numbers takes a lot of time, especially for bright pixels and many photons. You can decrease computation time by selecting "Approximate" which approximates the Poisson distribution with a Gaussian distribution with the correct variance. As you can see in the histogram, Poisson noise closely resebles Gaussian noise. However, there is an important difference in for dark image values!

You can see the difference to Gaussian noise in the stepwedge below.

Gaussian noise

In nature nearly everything is normally distributed. Normally distributed noise is Gaussian noise. It appears in image from thermal noise in the amplifier and other effects. An important aspect of Gaussian noise is that its variance does not depend on the intensity of the image.

Uniform noise

Uniform noise rarely occurs in nature but when digitizing a signal errors take place that are uniformly distributed. Like Gaussian noise the noise variance is independent of the image intensity.

Laplace noise

Laplace noise has a double exponential distribution. The scale parameter determines the width of the distribution.

Lorentz noise

Lorentz noise has Cauchy-Lorentz distribution which describes resonances and decays very slowly. This is a so called fat-tail distribution and causes here salt-and-pepper noise.

Comparison between noise types

In the images below the noise variance is the same for all noise types at a brightness of neutral gray (128) except for Lorentz noise where the variance is not defined.

dorylinux impaginatore

dorylinux — Thu, 20 Nov 2008 14:39:06 +0100

Questo script in python altro non è che una mia personalizzazione e relativa traduzione in italiano basato sul codice "Batch resize" di Carol Spears.
Ho volutamente messo i margini a zero perchè le miniature impaginate possano essere agevolmente tagliate ed ottenere delle piccole foto da un'impaginato grande. Io lo uso per creare in maniera del tutto automatica dei mini album partendo dall'impaginato grande, infatti ci sono pure le misure che uso io col mio laboratorio che stampa in banda 406mm. Si può comunque utilizzare pure per creare delle provinature nei vari formati.
Sappi che mettere i margini è un gioco da ragazzi, troverai nello script i miei commenti così da poter con poca fatica personalizzartelo da solo (vai al rigo 27).
Questa è una prima versione, considera che conosco un pò di php ma nulla di python, fortunatamente ci sono delle somiglianze. Se ho tempo e voglia vorrei migliorarlo, tipo sostituire i tasti radio con un menù a tendina, cosi da rendere l'interfaccia più piccolina ed aggiungere altri formati, tipo il fototessera e via dicendo.... si vedrà...
Per installarlo la procedura è la solita, scarichi il file e lo metti all'interno di: "/home/tuo_nome_utente/.gimp-2.6/plug-ins", poi avvi Gimp e te lo trovi su "Filtri > Batch".
Divertiti

Golden Mailing Labels

xobes — Mon, 17 Mar 2008 04:30:15 +0100

This python plugin reads names and addresses from a MySQL database and creates golden mailing labels (with optional return label).

I created this script out of the desire to have golden text on my wedding invitation and save the date envelopes. I may have taken this too far :-)

WARNING: Some understanding of SQL required.
Screen shots & Examples added (03-18-08)

The completed envelope(s) are either displayed or exported to a png or jpeg file. I found windows preview far more capable of printing than the GIMP (sorry everybody).

Unfortunately, while this works for me, it may need some tweaks to work for you.

What you will need:

- A working gimp/python setup (I've tested this only under windows XP so far)
- You will need the MySQLdb python module
- a MySQL server with the data you need: name, street1, street2, city, state, zip (street1 is the first line of the address, street2 is the second line).
- a golden environment map, see the tutorial at http://www.gimp.org/tutorials/Golden_Text/ for instructions and an example. It's hard to say that my script makes golden labels. Without a good envmap, it doesn't make anything at all worthwhile. I was reluctant to code up the creation of a golden envmap as part of the script because having it in there would remove control of the final product. Once you have an envmap, you may need to rotate it to tweak the brightness and shading to make things look right.

To make the return label I started up the python console (a wonderfully useful plugin) and imported the following script:
import gimpfu gimpfu.debug_environment = True from gimpfu import * import sys sys.path.append("C:\\Documents and Settings\\Andy\\.gimp-2.4\\plug-ins")

I then imported "golden_label" which was located in the path listed above. I then called the "golden" function with the appropriate arguments, thus bypassing the MySQL code entirely.

Feel free to edit and redistribute as you see fit (GPLv2+).
Any questions please feel free to send me an email (gmail) at: ajzobro

Blue Sky & Clouds

Darla — Sat, 26 Jan 2008 09:42:42 +0100

To fix burned out or white skies by adding clouds and a blue sky gradient (using a threshold mask).

Guide to Using the Blue Sky & Clouds Script