From XDSwiki

Labelit is a program for indexing diffraction patterns, which is bundled with Phenix. It may in principle substitute the COLSPOT and IDXREF steps of XDS.

Nick Sauter wrote on CCP4BB on Aug 25, 2011: I'd like to get any feedback from the community...the following feature was added to Labelit in March 2011 :

After indexing the images with LABELIT it is possible to write out an XPARM.XDS file that defines the unit cell, orientation, and beam parameters. For example, index an image first:

labelit.index lysozyme_001.img --index_only

This gives several possible Bravais lattice solutions...e.g. triclinic=1; tetragonal=9. Suppose you want XDS parameters for the tetragonal setting:

labelit.xds_xparm 9

That outputs the XPARM.XDS file.