XCF, short for eXperimental Computing Facility,[1] is the native image format of the GIMP image-editing program. It saves all of the data the program handles related to the image, including, among others, each layer, the current selection, channels, transparency, paths and guides.

XCF
Filename extension
.xcf
Internet media type
image/x-xcf
Magic numbergimp xcf 
Developed byGIMP
Container forGraphics
Open format?yes, but standard is ad hoc

Prior to version 4 (GIMP 2.10.0, released on 2018-04-27), the saved image data are compressed only by a simple RLE algorithm, but GIMP supports compressed files, using gzip, bzip2, or xz. The compressed files can be opened as normal image files. Since version 4, the image data can be compressed by zlib instead.

The XCF file format is backward compatible (all versions of GIMP can open earlier versions' files) and in some cases, forward compatible. For example, GIMP 2.0 can save text in text layers while GIMP 1.2 cannot. Text layers saved in GIMP 2.0 will open as ordinary image layers in GIMP 1.2. However, XCF files containing layer groups, a feature introduced in GIMP 2.7, cannot be opened with GIMP 2.6.

Despite some use in other programs[2][3][4][5][6] (see §software support), the use of XCF as a data interchange format is not recommended by the developers of GIMP, [7] since the format reflects GIMP's internal data structures and there may be minor format changes in future versions. Instead, a collaborative effort between the developers of GIMP and Krita is underway to design a standardised raster file format called OpenRaster (modelled on the OpenDocument format) for future use in both applications, and likely in others also.

GIMP's Save dialog saves in the XCF format: starting with version 2.8, other formats with import/export support were moved to an Export dialog.

Software support

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A partial list of image viewers and conversion software.

Selected software with some support for XCF
application XCF-capable? notes
GIMP default format program for which the format was developed
Seashore default format[2] lightweight native Mac OS X image editing program based on the GIMP
CinePaint default format, but nonstandard fork of GIMP with support for 16-bit and 32-bit floating point channels, and 16-bit integer channels; the XCF file format used in CinePaint has diverged from the GIMP's native format, so XCF files created in GIMP cannot be opened in CinePaint, and vice versa
DBGallery does not support colour indexing displays multi-layer non-indexed images and allows indexing, searching and other photo database operation
ImageMagick does not support colour indexing or multiple layers has an XCF reader module that can read single-layer non-indexed images
Project Dogwaffle see ImageMagick row (including PD Pro, PD Particles and PD Artist) imports XCF files using the ImageMagick library
Krita import only imports XCF files using the GraphicsMagick library
Kolourpaint Yes can read XCF files using KDE's image I/O library plugin, like any other KDE program
Gwenview does not support colour indexing can display multi-layer non-indexed images
Digikam does not support colour indexing can display multi-layer non-indexed images
Imagine does not support colour indexing or multiple layers can display single-layer non-indexed images
XnView does not support colour indexing or multiple layers can display single-layer non-indexed images
Inkscape export only[3] added support for XCF export in the 0.44 release
IrfanView requires plugin[4] can display multi-layer images (composite image and individual layers) with a plugin
Paint.NET requires plugin can load and save multi-layer .xcf/.xcfgz/.xcfbz2 images (via ImXCF.FileType plugin)
PhotoLine import only loads multi-layer images with layer masks and blend modes
Chasys Draw IES Yes can load and save multi-layer .xcf/.xcfgz/.xcfbz2 images (from version 3.71.02)
MediaWiki and thus Wikimedia Commons does not support colour indexing or later versions[5] supports XCF files that are compatible with GIMP 2.6 or 2.8, and when the color mode is RGB or grayscale
Corel Photo-Paint does not support layer mask or paths can load multi-layer images, support some layer modes
Photopea Yes online image editor which can open XCF files and convert to other formats including Photoshop's PSD
SDL2_image Yes[6] development library

References

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  1. ^ "Partial Specification of the XCF File Format". 2006-07-11. Retrieved 2014-05-21. The name XCF honors GIMP's origin at the eXperimental Computing Facility of the University of California at Berkeley.
  2. ^ a b "About". Seashore. Retrieved 2015-01-03.
  3. ^ a b "Inkscape 0.44 Release Notes". The new XCF output extension exports all top-level elements (i.e. layers and objects directly under root) as PNGs and assembles them into an XCF for processing in GIMP.
  4. ^ a b "IrfanView formats". Irfanview.com. Retrieved 1 March 2014.
  5. ^ a b "Commons:File types - Wikimedia Commons". commons.wikimedia.org. Wikimedia Commons. Retrieved 23 June 2020.
  6. ^ a b "Source code for SDL's XCF Loader". hg.libsdl.org. Retrieved 2018-06-09.
  7. ^ Neumann, Sven (2001-12-16). "Re: XCF support added to ImageMagick". gimp-developer (Mailing list).
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