A hierarchical syntax-based word alignment package for statistical machine translation
Jason Riesa's Nile Word Aligner - http://www.isi.edu/~riesa/software/nile
Main code repository: https://code.google.com/p/nile/
NILE is licensed with GPLv3
If you have changes, please consider contributing them back to the author - this is a working copy!
References:
"Feature-Rich Language-Independent Syntax-Based Alignment for Statistical Machine Translation" (J. Riesa, A. Irvine, and D. Marcu), Proceedings of EMNLP 2011.
"Hierarchical Search for Word Alignment" (J. Riesa and D. Marcu), Proceedings of ACL 2010.