File extension

.xcf

GIMP XCF image format

.xcf files are GIMP image files: the native layered format of the GNU Image Manipulation Program, storing layers, channels, paths, and selections.

Known meanings

Formats and reference material for .xcf

GIMP XCF image format

Native layered image format of GIMP

  • 2d-graphics
  • GIMP Development Team
Open link

Details

Format notes

XCF

XCF is the native file format of GIMP, the GNU Image Manipulation Program. The name comes from the Experimental Computing Facility at the University of California, Berkeley, where GIMP was created. Unlike flat formats such as PNG or JPEG, an XCF file preserves the editable state of an image, including layers with their blend modes and opacity, layer masks, channels, paths, guides, and selections.

Technical Structure

An XCF file starts with the signature gimp xcf followed by a version string (file for the earliest version, or v001, v002, and so on for later ones) and a null byte. The header continues with image dimensions, base color mode (RGB, grayscale, or indexed), and a list of properties, then offsets to layers and channels. Multi-byte values are stored in big-endian order. Pixel data is stored in tiles that can be run-length encoded or zlib compressed, depending on the version. Later versions changed offset sizes and added support for higher precision, so files written by recent GIMP versions may not open in older ones.

Adoption And Tooling

GIMP reads and writes XCF, and some other programs can import it, including Krita and ImageMagick (which flattens the layers). The format is documented in the GIMP project’s specification, which makes it more accessible than many layered formats. Files can be compressed with gzip or bzip2 (.xcf.gz, .xcf.bz2), which GIMP also reads.

Preservation Notes

XCF is suited to storing editable working files, while flattened formats should be exported for distribution. Record the GIMP version used, as version differences can prevent opening files in older software. Text layers and some effects may depend on installed fonts or filters.

Further Reading

  • GIMP XCF specification: https://developer.gimp.org/core/standards/xcf/