OpenRaster

OpenRaster is a file format for layered raster images. It is designed to be an open alternative to Photoshop's PSD format, and similar formats used by graphics editors. It uses ZIP as a container format.

Identification
One of the files in the ZIP container is named "", and its contents are the ASCII string "". Ideally, that's the first file in the container, and it's stored without compression.

Specifications

 * OpenRaster Specification
 * Draft OpenRaster Specification

Software

 * Krita
 * GIMP

Sample files

 * http://gitorious.org/openraster/openraster-example-files/trees/master
 * https://telparia.com/fileFormatSamples/archive/ora/

Related formats

 * XML - Used by some of the internal files
 * PNG - Used by some of the internal files

Links

 * Wikipedia article
 * http://www.freedesktop.org/wiki/Specifications/OpenRaster/