GIMP

In 1995, Spencer Kimball and Peter Mattis began developing GIMP—originally named General Image Manipulation Program—as a semester-long project at the University of California, Berkeley for the eXperimental Computing Facility.[7] The acronym was coined first, with the letter G being added to -IMP as a reference to "the gimp" in the scene from the 1994 film Pulp Fiction.[8]

1996 was the initial public release of GIMP (0.54).[9][10] The editor was quickly adopted and a community of contributors formed. The community began developing tutorials and artwork and sharing better work-flows and techniques.[11]

In the following year, Kimball and Mattis met with Richard Stallman of the GNU Project while he visited UC Berkeley and asked if they could change General in the application's name to GNU (the name of the operating system created by Stallman), and Stallman approved.[12] The application subsequently formed part of the GNU software collection.[13]

The first release supported Unix systems, such as Linux, SGI IRIX and HP-UX.[7][14] Since then, GIMP has been ported to other operating systems, including Microsoft Windows (1997, GIMP 1.1)[14] and macOS.

A GUI toolkit called GTK (at the time known as the GIMP ToolKit) was developed to facilitate the development of GIMP. The development of the GIMP ToolKit has been attributed to Peter Mattis becoming disenchanted with the Motif toolkit GIMP originally used. Motif was used up until GIMP 0.60.[10][15]

In recent versions (since the GIMP 2.9 build), the removal of the Lanczos image scaling algorithm, which had been used by GIMP and other image editing programs for many years, in favor of pushing forward the new NoHalo and LoHalo algorithms developed by Nicolas Robidoux, caused some controversy among GIMP users, with some users standing by the change but others expressing their dissatisfaction about it, due to mixed quality results in some image scaling scenarios, leading some users to keep using the older 2.8 version of GIMP simply because it's the last build with Lanczos support, and a few users giving up on using the application altogether as a result. To this day, several users hope to see a future version of GIMP with the Lanczos algorithm added back as an option for image resampling.[16][17][18]

GIMP is primarily developed by volunteers as a free and open source software project associated with both the GNU and GNOME projects. Development takes place in a public git source code repository,[38] on public mailing lists and in public chat channels on the GIMPNET IRC network.[39]

New features are held in public separate source code branches and merged into the main (or development) branch when the GIMP team is sure they won't damage existing functions.[38] Sometimes this means that features that appear complete do not get merged or take months or years before they become available in GIMP.

GIMP itself is released as source code. After a source code release, installers and packages are made for different operating systems by parties who might not be in contact with the maintainers of GIMP.

The version number used in GIMP is expressed in a major-minor-micro format, with each number carrying a specific meaning: the first (major) number is incremented only for major developments (and is currently 2). The second (minor) number is incremented with each release of new features, with odd numbers reserved for in-progress development versions and even numbers assigned to stable releases; the third (micro) number is incremented before and after each release (resulting in even numbers for releases, and odd numbers for development snapshots) with any bug fixes subsequently applied and released for a stable version.

Previously, GIMP applied for several positions in the Google Summer of Code (GSoC).[40][41] From 2006 to 2009 there have been nine GSoC projects that have been listed as successful,[40] although not all successful projects have been merged into GIMP immediately. The healing brush and perspective clone tools and Ruby bindings were created as part of the 2006 GSoC and can be used in version 2.8.0 of GIMP, although there were three other projects that were completed and are later available in a stable version of GIMP; those projects being Vector Layers (end 2008 in 2.8 and master),[42] and a JPEG 2000 plug-in (mid 2009 in 2.8 and master).[43] Several of the GSoC projects were completed in 2008, but have been merged into a stable GIMP release later in 2009 to 2014 for Version 2.8.xx and 2.10.x. Some of them needed some more code work for the master tree.

Second public Development 2.9-Version was 2.9.4 with many deep improvements after initial Public Version 2.9.2.[44][45] Third Public 2.9-Development version is Version 2.9.6.[46] One of the new features is removing the 4 GB size limit of XCF file.[47][48] Increase of possible threads to 64 is also an important point for modern parallel execution in actual AMD Ryzen and Intel Xeon processors. Version 2.9.8 included many bug fixes and improvements in gradients and clips.[49] Improvements in performance and optimization beyond bug hunting were the development targets for 2.10.0.[50] MacOS Beta is available with Version 2.10.4.[51]

The next stable version in the roadmap is 3.0 with a GTK3 port.[52] 2.99-Series is the development Series to 3.0.

GIMP developers meet during the annual Libre Graphics Meeting.[53] Interaction designers from OpenUsability have also contributed to GIMP.[54]

Mascot

GIMP's mascot is called Wilber and was created in GIMP by Tuomas Kuosmanen, known as tigert, on 25 September 1997. Wilber received additional accessories from other GIMP developers, which can be found in the Wilber Construction Kit, included in the GIMP source code as /docs/Wilber_Construction_Kit.xcf.gz.[55]

The current version of GIMP works with numerous operating systems, including Linux, macOS and Windows. Many Linux distributions, such as Fedora Linux[56] and Debian.[57][58], include GIMP as a part of their desktop operating systems.

GIMP began to host its own downloads after discontinuing use of SourceForge in 2013.[59] The website later repossessed GIMP's dormant account and hosted advertising-laden versions of GIMP for Windows.[60]

Lifewire reviewed GIMP favorably in March 2019, writing that "[f]or those who have never experienced Photoshop, GIMP is simply a very powerful image manipulation program," and "[i]f you're willing to invest some time learning it, it can be a very good graphics tool."[61]

GIMP's fitness for use in professional environments is regularly reviewed; it is often compared to and suggested as a possible replacement for Adobe Photoshop.[62][63] GIMP has similar functionality to Photoshop, but has a different user interface.[64]

GIMP 2.6 was used to create nearly all of the art in Lucas the Game, an independent video game by developer Timothy Courtney. Courtney started development of Lucas the Game in early 2014, and the video game was published in July 2015 for PC and Mac. Courtney explains GIMP is a powerful tool, fully capable of large professional projects, such as video games.[65]

The single-window mode introduced in GIMP 2.8 was reviewed in 2012 by Ryan Paul of Ars Technica, who noted that it made the user experience feel "more streamlined and less cluttered".[66] Michael Burns, writing for Macworld in 2014, described the single-window interface of GIMP 2.8.10 as a "big improvement".[67]

In his review of GIMP for ExtremeTech in October 2013, David Cardinal noted that GIMP's reputation of being hard to use and lacking features has "changed dramatically over the last couple years", and that it was "no longer a crippled alternative to Photoshop". He described GIMP's scripting as one of its strengths, but also remarked that some of Photoshop's features – such as Text, 3D commands, Adjustment Layers and History – are either less powerful or missing in GIMP. Cardinal favorably described the UFRaw converter for raw images used with GIMP, noting that it still "requires some patience to figure out how to use those more advanced capabilities". Cardinal stated that GIMP is "easy enough to try" despite not having as well developed documentation and help system as those for Photoshop, concluding that it "has become a worthy alternative to Photoshop for anyone on a budget who doesn't need all of Photoshop's vast feature set".[68]

The user interface has been criticized for being "hard to use".[69]

Animation Showing Brushes, Patterns, Gradients Created in GIMP

Tools used to perform image editing can be accessed via the toolbox, through menus and dialogue windows. They include filters and brushes, as well as transformation, selection, layer and masking tools.

Image editing

There are many tools that can be used for editing images in GIMP. The more common tools include a paint brush, pencil, airbrush, eraser and ink tools used to create new or blended pixels. The Bucket Fill tool can be used to fill a selection with a color or pattern. The Blend tool can be used to fill a selection with a color gradient. These color transitions can be applied to large regions or smaller custom path selections.

GIMP also provides "smart" tools that use a more complex algorithm to do things that otherwise would be time-consuming or impossible. These include:

• Clone tool, which copies pixels using a brush
• Healing brush, which copies pixels from an area and corrects tone and color
• Perspective clone tool, which works like the clone tool but corrects for distance changes
• Blur and sharpen tools
• The Smudge tool can be used to subtly smear a selection where it stands
• Dodge and burn tool is a brush that makes target pixels lighter (dodges) or darker (burns)

Animation showing three docked and tabbed dialogs: layers, channels, and paths

Layers, layer masks and channels

An image being edited in GIMP can consist of many layers in a stack. The user manual suggests that "A good way to visualize a GIMP image is as a stack of transparencies," where in GIMP terminology, each level (analogous to a transparency) is called a layer.[72] Each layer in an image is made up of several channels. In an RGB image, there are normally 3 or 4 channels, each consisting of a red, green and blue channel. Color sublayers look like slightly different gray images, but when put together they make a complete image. The fourth channel that may be part of a layer is the alpha channel (or layer mask). This channel measures opacity where a whole or part of an image can be completely visible, partially visible or invisible. Each layer has a layer mode that can be set to change the colors in the image.[73]

Text layers can be created using the text tool, allowing a user to write on an image. Text layers can be transformed in several ways, such as converting them to a path or selection.[74][75]

Droste effect using Mathmap plug-in

Because of the free and open-source nature of GIMP, several forks, variants and derivatives of the computer program have been created to fit the needs of their creators. While GIMP is cross-platform, variants of GIMP may not be. These variants are neither hosted nor linked on the GIMP site. The GIMP site does not host GIMP builds for Windows or Unix-like operating systems either, although it does include a link to a Windows build.

An animated GIF generated by GAP plugin

GIMP's functionality can be extended with plugins. Notable ones include:

• GIMP-ML, which provides machine learning-based image enhancement.[101] GIMP-ML with python 3 is next target in development.[102]
• GIMP Animation Package (GAP), official plugin for creating animations. GAP can save animations in several formats, including GIF and AVI.[103]
• Resynthesizer, which provides content-aware fill. Original part of Paul Harrison's PhD thesis,[104] now maintained by Lloyd Konneker.[105]
• G'MIC, which adds image filters and effects.[106]

• Montabone, Sebastian (2010). Beginning Digital Image Processing: Using Free Tools for Photographers. Berkeley, California: Apress. ISBN 978-1-4302-2841-7.
• Peck, Akkana (16 December 2008). Beginning GIMP: From Novice to Professional (2nd ed.). Berkeley, California: Apress. ISBN 978-1-4302-1070-2.
• Bunks, Carey (15 February 2000). Grokking the GIMP. Indianapolis, Indiana: New Riders Press. ISBN 978-0-7357-0924-9. Retrieved 21 December 2013.
• Lecarme, Olivier; Delvare, Karine (January 2013). The Book of GIMP. San Francisco, California: No Starch Press. ISBN 978-1-59327-383-5. Retrieved 7 March 2014.

Wikibooks has more on the topic of: GIMP

Wikimedia Commons has media related to GIMP.

Wikiversity has learning resources about GIMP basics

• Official website
• GIMP at Curlie
• GIMP at Open Hub