Multilingual Region-Dependent Transforms

This shell package allows to extract features based on Region Dependent Transforms (RDT) models from audio files. The features are well suitable mainly for Gaussian Mixture Models (GMM) in Automatic Speech Recognition (ASR) systems but they could be used in other applications as well.

The whole process could be split into 3 steps. Standard PLP-HLDA features are concatenated with Stacked Bottle-Neck Features trained in multilingual fashion on Babel data coming from 17 different languages. This features are going into discriminatively trained RDT transforms on 17 Babel languages which generates final outputs.

The models can be downloaded from

and the RDT forwarding script is available in


The models (pretrained networks) are released for noncommercial usage under CC BY-NC-ND 4.0 license ( and shell code under Apache 2.0 ( For any other use, please contact Jan Cernocky.


KARAFIAT Martin, BURGET Lukas, GREZL Frantisek, VESELY Karel and CERNOCKY Jan. Multilingual Region-Dependent Transforms. In Proceedings of the 41th IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP 2016), 2016. Shanghai: IEEE Signal Processing Society, 2016, pp. 5430-5434. ISBN 978-1-4799-9988-0.

Available from: