G'MIC 3.4.0 : Image Processing in Its Prime!

3.4.0

GREYC's Magic for Image Computing

16th anniversary

Table of Contents

Note : Click on the images of the article, to get a full-resolution version, or to play a video when the images contain the icon ` : Click on the images of the article, to get a full-resolution version, or to play a video when the images contain the icon `

1. G'MIC in a Nutshell

G'MIC

Krita

Fig. 1.1. Preview of the G'MIC -Qt plugin version 3.4.0 , running in GIMP 2.10, with the Comicbook filter selected.

2. What's New in Version 3.4.0 ?

3.4.0

G'MIC

stability

long-term support

G'MIC's

Application Programmer's Interfaces (APIs):

G'MIC

C++

G'MIC

3.4.x

3.4.0

3.3

3.4

G'MIC Online ( G'MICol ): This web service allows users to apply G'MIC filters to their uploaded images through their web browsers. It has existed for several years, largely unchanged from its original form, while interactive web techniques have advanced. In 2024, the Application Development and Deployment ) team at the GREYC laboratory undertook a complete overhaul of G'MIC Online . The web service now sports a new look, employs significant user interface improvements, with more intuitive widgets, an enhanced preview window, a choice between light and dark themes, revamped handling of filter favorites and better integration of the web service with the G'MIC core, such that web users can now access recently developed filters and image processing pipelines. ): This web service allows users to applyfilters to their uploaded images through their web browsers. It has existed for several years, largely unchanged from its original form, while interactive web techniques have advanced. In 2024, the DDA ) team at thelaboratory undertook a complete overhaul of. The web service now sports a new look, employs significant user interface improvements, with more intuitive widgets, an enhanced preview window, a choice between light and dark themes, revamped handling of filter favorites and better integration of the web service with thecore, such that web users can now access recently developed filters and image processing pipelines.

Fig.2.1. Preview of the revamped G'MIC Online web service released with version 3.4.0 (here with the light theme).

DDA

G'MIC -Qt Plugin : Over the past year, the plugin has acquired more than 40 new image processing filters , Random Parameters button, which generates arbitrary filter settings, furnishing rapid previews that can be quickly evaluated for practical or aesthetic worth. : Over the past year, the plugin has acquired more than detailed below . Many employ the newbutton, which generates arbitrary filter settings, furnishing rapid previews that can be quickly evaluated for practical or aesthetic worth.

Fig.2.2. G'MIC -Qt Plugin: The new Random Parameters button assigns random values to the selected filter's parameters.

gmic CLI Tool : All filters created by the developer community are now integrated within the command-line tool executable. There are no longer discrepancies in the number of default filters available between the G'MIC -Qt plugin and the gmic CLI tool. Previously, users needed to force filter updates with $ gmic update to align environments.

gmic

4000 functions

display

Fig.2.3. gmic CLI Tool: The G'MIC image viewer has been completely re-implemented and allows viewing different image types within the same interface.

plot

Fig.2.4. gmic CLI Tool: The G'MIC viewer for mathematical functions or 1D signals has also been re-implemented.

gmic

Other Improvements:

The integrated mathematical expression evaluator has evolved significantly: it is one of the essential bricks of the G'MIC language, as it is responsible for evaluating the results of the mathematical operations needed in scripts (needless to say, calculations are done all the time in image processing). This evaluator has been enriched with many new functions, especially for the calculation and processing of vectors and matrices, and native manipulation of heaps.

Many native ( C++ ) functions formerly in the shared binary object library have now been entirely rewritten in the G'MIC language. This facilitates their maintenance and further development, as future work can be scripted for immediate effect, instead of being subject to compilation and linking. Situated at the script level, such modifications become immediately available to users, as distribution of binaries will no longer be required.

The commands for loading/saving 3D meshes in .obj ( Wavefront ) format have been improved, and new commands for processing/creating 3D meshes have emerged (e.g., to visualize the normal vectors at the vertices of a mesh, as illustrated in the video below). And, no, this is not a rotten apple:

Fig.2.5. 3D mesh management within G'MIC has been enriched with new commands.

G'MIC

3. Details of the New Filters

Distortion Filters

Degradation Filters

3.1. Photo Retouching

G'MIC -Qt

Colors / Mixer [Generic]

Fig.3.1.1. The Colors / Mixer [Generic] filter enriches the already available arsenal of filters for contrast and color enhancement.

Details / Sharpen [Alpha]

Details/Sharpen [Alpha]

Fig.3.1.2. The Details / Sharpen [Alpha] filter allows for fine detail enhancement in photographs, minimizing the appearance of halos.

Fig.3.1.3. Before/After details illustrating the outcome of the Details / Sharpen [Alpha] filter.

Layers / Spatial Blend Multi-Layers

Fig.3.1.4. The Layers / Spatial Blend Multi-Layers filter allows for merging multiple photographs with an adjustable spatial linear gradient.

Credits

Rumble Viral

G'MIC -Qt

GIMP 2.10

3.2. Distortion Filters

Deformations / Distort [RBF]

Fig.3.2.1. The Deformations / Distort [RBF] filter allows for various distortions based on RBFs. Here, specifying the radial basis function phi(r) = log(0.1+r).

Map Projection

Kristian Järventaus

Fig.3.2.2. The new Map Projection filters offers several geographical map projection algorithms.

Deformations / Square to Circle [alt]

Fig.3.2.3. The Deformations / Square to Circle [alt] filter allows converting square or rectangular objects into round or elliptical objects, and vice versa.

Deformations / Poincaré Disk

Fig.3.2.4. Some examples of Poincaré disks, generated by the Deformations / Poincaré Disk filter.

Fig.3.2.5. Projection of an image onto a Poincaré disk.

"Flyover of the Poincaré Planet"

3.3. Degradation Filters

degrade

G'MIC

Rendering / CRT Scanlines and Degradations / CRT Phosphors filters mimic the image display of GREYC laboratory. Theandfilters mimic the image display of cathode-ray tubes (CRT) , by simulating two characteristic effects of CRT displays, namely the Scanline effect and phosphor excitation . These two filters were created in collaboration with Romain Hérault , a new contributor who recently joined thelaboratory.

Fig.3.3.1. The Rendering / CRT Scanlines filter imitates the typical scanline effect of CRT displays.

Fig.3.3.2. The Degradations / CRT Phosphors filter simulates the phosphor display technique of CRT displays.

The Degradations / Blur [Motion] filter emulates path-based motion blur, with user-adjustable, spline-based trajectories which may be directly altered through key points in the G'MIC -Qt preview window:

Fig.3.3.3. The Degradations / Blur [Motion] filter simulates motion blur.

Degradations / Sloppy Mess filter is intended for Glitch Art enthusiasts. It's one of the first filters by a new contributor, G'MIC language for filter creation. This effect offers wide-ranging parameters to produce a panoply of disjoint and disassociated outputs. Thefilter is intended for Glitch Art enthusiasts. It's one of the first filters by a new contributor, Prawnsushi , who recently took an interest in thelanguage for filter creation. This effect offers wide-ranging parameters to produce a panoply of disjoint and disassociated outputs.

Fig.3.3.4. The Degradations / Sloppy Mess filter deliberately creates artistic digital artifacts on your images.

3.4. Rendering and Texture Filters

The Rendering / Underwoods filter, another creation of Prawnsushi , is nothing less than an underwood generator ! One might say it's not very useful, and indeed it's not a filter that image processors, photographers, or illustrators will incorporate into their daily work.

G'MIC

algorithmic creativity

G'MIC

all kinds of filters

free sharing

cognoscenti

G'MIC

Fig.3.4.1. Examples of underwood image renderings by the Rendering / Underwoods filter.

Patterns / Reaction-Diffusion filter synthesizes textures modeled after Thefilter synthesizes textures modeled after reaction-diffusion systems

Fig.3.4.2. The Patterns / Reaction-Diffusion filter in the G'MIC -Qt plugin.

G'MIC

Deformations / Drop Water

Rendering / Spline Spirograph filter is inspired by the Random Parameters button in the G'MIC -Qt plugin is particularly welcome here, as it quickly obtains a varied panorama of diverse results! Thefilter is inspired by the Spirograph game for generating parametric curves, creating intriguing texture and color effects. The presence of thebutton in theplugin is particularly welcome here, as it quickly obtains a varied panorama of diverse results!

Fig.3.4.3. The Rendering / Spline Spirograph filter and some rendering examples.

The Rendering / ABN Filigrees filter also knows how to draw interesting parametric curves, inspired this time by the filigrees found on stock certificates or paper money. This filter pays homage to the American Bank Note Company , an engraver of financial paper, active on Wall Street from the 19th century until sixty years ago.

Fig.3.4.4. The Rendering / ABN Filigrees filter.

The Rendering / Random Signature filter is also an amusing curve generator: it aims to draw random signatures, as illustrated in the video below:

Fig.3.4.5. The Rendering / Random Signature filter creates random signatures.

And to finish this section, let's mention the Rendering / Twisted Rays filter which, as its name suggests, generates a twisted rays effect. The use of this filter will probably remain quite unfathomable in the near term. But, even now, there may be among thousands of G'MIC users a creator seeking this precise effect — and now they can! ☺

Fig.3.4.5. The Rendering / Twisted Rays filter creates a swirl of rays on your images.

3.5. Artistic Effects

G'MIC

The Artistic / Stringify filter decomposes an input image into quantized color blobs and connects the points (subsampled) located on the contours of these blobs with color segments. The rendering may resemble the curves obtained with the Spirograph game.

Fig.3.5.1. The Artistic / Stringify filter creates image abstractions from color segments.

The Black & White / Filaments filter is based on the projection of thousands of particles from one or more edges of the image, with trajectories deformed by the image's contour geometry. The drawing of these thousands of trajectories with semi-transparent colors produces images like these:

Fig.3.5.2. The Black & White / Filaments filter transforms your images into sets of deformed filaments.

The Arrays & Tiles / Loose Photos filter simulates an effect of throwing photos haphazardly on a table, so that the content of the photos constitutes a global image, as specified by the filter's settings. Many parameters are adjustable (density, size and ratio of photographs, shading parameters, etc.), giving the user a great deal of freedom over the final rendering.

Fig.3.5.3. Example of rendering by the Arrays & Tiles / Loose Photos filter.

The Rendering / Quick Copyright filter, which already existed in previous versions, has been re-implemented from scratch. It facilitates the insertion of a copyright text (or text signature) on a digital image. It now has many parameters to finely adjust the position of the text, its size, font, and other aspects. Combined with the automation capabilities of the G'MIC language, this filter is suited for easily inserting text, in a standardized way, on thousands of photographs.

Fig.3.5.4. The Rendering / Quick Copyright filter in action for inserting copyright text on an image.

Patterns / Random Rectangles filter transforms an image into a random partition of colored rectangles, giving an abstract image effect, vaguely in the manner of Finally, thefilter transforms an image into a random partition of colored rectangles, giving an abstract image effect, vaguely in the manner of Piet Mondrian

Fig.3.5.5. The Patterns / Random Rectangles filter creates a colorful partition of randomly placed rectangles on the image.

4. A Software with Varied Uses

G'MIC

Denoising JWST Images:

G'MIC

ESA

JWST

Repair / Banding Denoise

G'MIC

M.J. McGaughrean

Fig.4.1. Use of G'MIC for denoising images of the Herbig-Haro 211 protostar, acquired by the JWST.

G'MIC

Creative Coding:

G'MIC

Fig.4.2. Snowflake animation generated by a G'MIC script.

0: a rock

1: paper

2: scissors

Drop Water

"Hell's Soup"

Fig.4.3. Rock-Paper-Scissors game animation, where all the pixels in an image play simultaneously.

Fig.4.4. Rendering of the Mandelbrot Set using the Orbit Trap method.

z_[n+1]=z_[n]^p + c

p=2

Fig.4.5. Fractal variations around the Buddhabrot.

Buddhabrot

Image Conversion for String Art :

G'MIC

Fig.4.6. More or less successful attempt to use G'MIC for String Art.

G'MIC