What is X3F, and why this page?
X3F is a file format for Sigma cameras, containing Foveon based images. I assume, as you are here, that this makes perfectly sense to you :)
The reason for this page is that I (Roland) am interested in the Foveon technology and that I have written some software to read X3F files. It all started by me reading news in rec.photo.digital in 2001 or so. And then later reading the Sigma SLR forum at DPReview.
Open Source
We have chosen to make these tools open source, under an BSD lookalike license. The source plus executables for Linux, OS-X and Windows can be found here: x3f.tgz (build 016).
Installation
No installation. Executables can be found in the three directories linux, osx and windows in the downloaded file.
The info tool
This is really a test program - doing nothing of any great value. It shows how to use the X3F IO library for reading and writing X3F files. It also dumps some information about the file. It is used thus:
x3f_io_test foo.x3f
The extract tool
This tool can extract the RAW Foveon sensor data and dump it as TIFF (or RAW). By default the data is scaled and gamma coded. It can also dump the JPEG (thumbnail) file. It is used thus:
x3f_extract -raw [-noscale] foo.x3f
x3f_extract -jpg foo.x3f
The first will create a file called foo.x3f.tif and the second foo.x3f.jpg. The x3f_extract tool can take several input files, i.e. work in batch mode.
The Foveon RAW format
The Foveon/Sigma RAW format is a false color three channel image. The x3f_extract tool cannot (currently) convert to real RGB colors. Thats the aim though. We will see.
DP1 RAW extraction unsupported
Currently Sigma do not disclose the DP1 RAW format. Therefore does this tool not support extraction of the RAW data for DP1. We are in good company - as the same goes for Adobe and Apple.
Support OpenRAW
We believe that the format of a file that is produced by your camera shall be known to you, the photographer. It is your digital negative and you shall be able to use it. E.g., if you are a programmer you shall be able to write your own software handling it or you shall be able to benefit from commercial or free third party software.
Therefore we support the OpenRAW initiative.
