The MegaMorph version of FERENGI.
FERENGI: Full and Efficient Redshifting of Ensembles of Nearby Galaxy Images
See here for details of the original version, described in this paper: Barden, Jahnke & Häußler, 2008, ApJS, 175, 105.
The MegaMorph project (specifically Bamford, Häußler and Vika) has added a few options to FERENGI, and ensured that it works correctly for redshifting low-redshift SDSS to how they would appear at slightly higher redshift, but still observed by the SDSS survey.
This code is used in the paper: Vika et al., 2013, MNRAS, 435, 623.