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GIMP

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GIMP
Developer(s)The GIMP Team
Repository
Operating systemCross-platform
Available inMultilingual[1]
TypRaster graphics editor
LicenseGNU General Public License
Websitewww.gimp.org

The GNU Image Manipulation Program, or GIMP, is a raster graphics editor used to process digital graphics and photographs. Typical uses include creating graphics and logos, resizing and cropping photos, altering colors, combining multiple images, removing unwanted image features, and converting between different image formats. GIMP can also be used to create basic animated images in GIF format. It is often used as a free software replacement for Adobe Photoshop, the most widely used bitmap editor in the printing and graphics industries; however, it is not designed to be a Photoshop clone.[2] The project's mascot is a coyote named Wilber.

The project was started in 1995 by Spencer Kimball and Peter Mattis and is now maintained by a group of volunteers under the auspices of the GNU Project. The latest version of GIMP, v.2.4.3 was released in December, 2007. Available under the terms of the GNU General Public License, GIMP is free software.

History

GIMP originally stood for General Image Manipulation Program. Its creators, Spencer Kimball and Peter Mattis, initially started GIMP as a semester-long project for a class at the University of California, Berkeley. Both were integral members of experimental Computing Facility, a student club at Berkeley. In 1997, after both Kimball and Mattis had graduated from Berkeley, the name was changed to GNU Image Manipulation Program when it became an official part of the GNU Project. A version 2 was released in 2005.

Eigenschaften

Brushes dialog in GNOME

GIMP's manipulation tools can be accessed via the toolbox, menu paths, and dialog boxes (which are also known as palettes). They include filters and brushes, as well as transformation, selection, layer and masking tools.

For example, GIMP comes with 48 standard brushes, plus facilities to create new ones. Brushes (and brush tools) can be used in hard-edged, soft-edged, or eraser modes, be applied at different opacities, or used with different modes for composition.

Color support

Gradients dialog in GNOME

GIMP also has a palette with RGB, HSV, color wheel, CMYK, and mixing modes, plus tools to pick colors from the image with various averaging options. There is support for hexadecimal color codes (as used in HTML). (Note that 'CMYK' colors are immediately translated into RGB when used; GIMP does not have any built-in support CMYK mixtures that cannot be represented in RGB, such as rich blacks, though they can be simulated to a limited extent with third-party add-ons.)

GIMP supports gradients, which integrate into its other tools (such as brushes and fills) to shade image areas with automated color blending. It includes a variety of built-in gradients, and as with the brushes, also allows the user to customize and create their own gradient fills.

Selection and masking tools

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

GIMP can perform rectangular or circular selection, freehand selection, and "by color" selection. Alternatively, the Smart Selection tool, known as the "Magic Wand", can be used to select contiguous regions. The Intelligent Scissors (iScissors) tool can be used to auto-create paths between regions defined by strong color-changes.

GIMP has support for layers, including transparent layers, which can be shown, hidden, or made semitransparent. It also supports transparent and semitransparent images. Channels add different types of opacity and color effects to images.

Paths

Paths containing line segments or Bezier curves can be created using the Ink tool. Paths can be named, saved, and painted (or "stroked") with brushes, patterns, or various line styles. Paths can also be used to create complex selections.

Effects, scripts and filters

GIMP has approximately 150 standard effects and filters, including Drop Shadow, Blur, Motion blur and Noise.

GIMP operations can be automated with scripting languages. A Scheme interpreter named Gimp-Fu is built in, and external Perl, Python, or Tcl can be used. Ruby support is in experimental development. These scripts and plugins for GIMP can be used interactively, or combined non-interactively.

Development

GIMP's user interface is built using GTK+, a widget toolkit originally written for the program. GTK+, as the GIMP Toolkit, was initially a part of the GIMP source tree, but has since been refactored due to its usefulness outside the scope of GIMP. GTK+ is also used as the widget toolkit for the GNOME desktop environment. GTK+ was intended as a replacement for Motif, a proprietary toolkit on which GIMP originally depended. GIMP and GTK+ were originally designed for the X Window System running on Unix-like operating systems, but have since been ported to Microsoft Windows, OS/2, and SkyOS.

The current stable version of GIMP is Template:Latest stable release/GIMP. Major changes compared to version 1.2 include a more polished user interface, further separation of the user interface and back-end and the ability to use brushes that would normally only be able to be used on Photoshop programs.

For the future it is planned to base GIMP on a more generic graphical library called GEGL, thereby addressing some fundamental design limitations that prevent many enhancements such as native CMYK support. Implementation of this plan was continually put off from 2000 until October 2006, when developer Øyvind Kolås demonstrated a limited working version of GEGL, including a new graphical interface, that had been developed by Sven Neumann, Michael Natterer, and Kolås.[3]

GIMP's next version, 2.6, will feature a heavily modified GUI by a specialized user-interface company MMIWorks.[4]

Distribution

File:Gimp 240 wikitest.png
GIMP 2.4.0 running on Windows Vista

GIMP is available for a variety of operating systems and computer architectures. There are a number of variations and derivative programs, including ports to other operating systems and forks with task- or OS-specific modifications. The GIMP website does not distribute compiled versions of GIMP, only the project's source code.

GIMP 2.2.8 running under X11 on Mac OS X

GIMP is included as the standard image editor on most general purpose Linux distributions, including Debian GNU/Linux, Ubuntu, Mandriva, SUSE, and Fedora.

A port of GIMP to Microsoft Windows was started by Finnish programmer Tor "tml" Lillqvist in 1997. The GIMP website links to binary installers compiled by Jernej Simoncic for the platform.[5]

Variants

GIMPVS is a GTK+ and Gimp Distribution compiled using Microsoft compilers. The Distribution aims at providing artists a stable Gimp on Microsoft platforms and developers access to GTK+ and Gimp development directly from Microsoft Visual Studio (2005 and 2008 editions ).The latest GTK libraries are included GTK 2.15.0 comes ready to use in both Debug and Release versions [6]

Seashore is a program based on GIMP for Mac that uses the native Cocoa interface in Mac OS X. The program is currently in beta (0.1.9) and includes only a small subset of the many filters available in GIMP.

Gimp.app provides a self-contained application bundle of GIMP for Mac OS X. Gimp.app has many features that Seashore does not have, but being built upon the GTK for its GUI features, it requires a version of Apple's X11 to run it.[7]

A project named osx-gimp provides native builds of GIMP on Mac OS X using GTK+ built for Quartz. It is mostly functional, but there is currently limited support for the Quartz backend of GTK+, and it is considered a beta version.[8]

CinePaint, formerly known as "Film Gimp", is a fork of GIMP version 1.0.4, used for frame-by-frame retouching of feature film. The present "Film Gimp" version supports up to 32-bit IEEE-floating point color depth/channel. Unlike GIMP, CinePaint has support for color management, HDR, and much more. CinePaint is used primarily within the film industry due mainly to its support of high-fidelity image formats.

Interface and usability

As an application originally intended only for the X Window System, GIMP does not interfere with window management and instead entirely delegates this responsibility to the window manager. Consequently, GIMP uses a (controlled) single document interface, and it also uses multiple windows for its tools, color palette, and so forth. This is unlike many other graphics programs, which use a multiple document interface or an SDI with integrated toolbars. This provides additional flexibility, as windows are not constrained inside a larger container window. A downside is the possibility of desktop clutter on systems without strong window management capabilities or virtual desktops, such as Microsoft Windows. GIMPshop is a modification to GIMP, rearranging its user interface to mimic that of Adobe Photoshop, including the use of a multiple document interface, renamed functions, and rearranged menus.

GIMP is often criticized as having usability problems.[9] A special edition called Instrumented GIMP was created at the University of Waterloo, which tracks and reports user interaction with the program, to generate statistics to guide future improvements.

Comparison and compatibility with Adobe Photoshop

GIMP is sometimes proffered as a replacement for the commercial Adobe Photoshop software. Thus, comparisons between the two are often a topic of spirited debate.[10] There are significant differences between the two packages. For example, Photoshop is not compatible with GIMP plugins or scripts. GIMP features offer no or (with the PSPI plug-in) very weak support for plugins designed for Photoshop, such as 8BF filters.[11]

Photoshop does not support GIMP's native XCF file format, but GIMP can read and write most Photoshop native PSD format files.

Like Photoshop, GIMP features support for 8-bit per-channel images. Its Intelligent Scissors are similar to Photoshop's Magnetic Lasso tool, and many basic tools and filters have identical functionality in both.

Photoshop features several advantages in color management that GIMP lacks. Photoshop has support for 16-bit, 32-bit, and floating point images,[12] support for the Pantone color matching system, or spot color and support for color models other than RGB(A) (such as CMYK) and greyscale, such as CIE XYZ.[13] GIMP does not support Pantone colors because such use requires a large fee, which open source developers usually do not have access to. [14] Photoshop features extensive gamma correction support.

In addition, Photoshop contains several productivity features and tools not supported by GIMP, such as native support for Adjustment layers (layers which act like filters),[15] undo history "snapshots" that persist between sessions, the history brush tool, folders in the layer window, a free transform tool to rotate, scale and move in one tool, text blending options like drop shadow and glow, and an interpolation code to draw smooth brush strokes using a tablet. GIMP also requires basic programming knowledge to build an automation upon it, usually Script-Fu (scheme) or Python-Fu, while Photoshop can record the user's actions and repeat them with a "Play" button. However, Photoshop's automation is not as powerful as GIMP's.[16]

GIMP's open development model means that it is much more readily available and at zero cost, on more operating systems, plugin development is not limited by developers and as such has no need to compete with Photoshop; by comparison, access to Adobe Photoshop's SDK requires authorization[17] and the commercially produced software is in competition with Corel Paint Shop Pro as well as the other Open Source, GNU or otherwise freely available manipulation applications.

File types

GIMP has support for opening and saving to a large number of different file formats.[18] Its native format is XCF, named after the computing facility where GIMP was authored.

GIMP has read/write support for popular image formats such as bitmap, JPEG, PNG, GIF and TIFF, along with the file formats of several other applications such as Autodesk flic animations, Paintshop Pro images and Adobe Photoshop Documents. Other formats with read/write support include PostScript documents, X bitmap image and Zsoft PCX. GIMP can also read and write path information from SVG files.

GIMP can import Adobe PDF documents and the raw image formats used by many digital cameras, but cannot save to these formats.

GIMP can export to MNG layered image files and HTML (as a table with coloured cells), C source code files (as an array) and ASCII Art (using a plugin to represent images with characters and punctuation making up images), though it cannot read these formats.

See also

References

  1. ^ See List of available languages of the user manual
  2. ^ https://lists.xcf.berkeley.edu/lists/gimp-developer/2007-August/018486.html
  3. ^ "The GIMP's next-generation imaging core demonstrated".
  4. ^ Evaluation notes on photo realism, photo composing, icon design and creating web images at the GIMP's UI wiki
  5. ^ "GIMP - Windows installers". {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
  6. ^ http://gimp-vs.sourceforge.net/
  7. ^ http://gimp-app.sourceforge.net/
  8. ^ http://osx-gimp.sourceforge.net/
  9. ^ Dave Neary (2006-09-18). "The GIMP usability". Safe as Milk blog. Retrieved 2007-07-29. {{cite web}}: Check date values in: |date= (help)
  10. ^ "The Gimp from the Eyes of a Photoshop User". 2004-30-04. Retrieved 2008-01-12. {{cite web}}: Check date values in: |date= (help); Unknown parameter |publicher= ignored (help)
  11. ^ There is a plugin called PSPI for Windows and Linux versions of GIMP, which allows the use of the 8bf Adobe Photoshop filters in the GIMP. It however requires the Adobe Photoshop SDK to compile, the use of which must be requested from Adobe, but pre-compiled versions are freely distributable.
  12. ^ GIMP has limited support through LCMS; "LittleCms, Great color at small footprint". {{cite web}}: Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
  13. ^ partial CMYK support is available with the Separate plug-in.
  14. ^ McClure, Philip (2007-01-11). "Gimp vs. Photoshop". GRIMTHING.COM. Retrieved 2008-01-03.
  15. ^ A plugin is available which adds some support for these; this is planed for GIMP 2.6 with the introduction of the GEGL library
  16. ^ Kuniavsky, Mike (1999-03-12). "Bring Out the GIMP". Web Monkey. Lycos, Inc. Retrieved 2008-01-03. {{cite web}}: Check date values in: |date= (help)
  17. ^ http://partners.adobe.com/public/developer/photoshop/devcenter.html
  18. ^ http://www.gimphelp.org/formats.shtml