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Institute for Telecommunication Sciences / Resources / Audio Quality Research / ABC-MRT

ABC-MRT16 and ABC-MRT

ABC-MRT is short for Articulation Band Correlation Modified Rhyme Test. This is an objective estimator of speech intelligibility that follows the paradigm of the Modified Rhyme Test (MRT).  ABC-MRT is the name of the original algorithm and ABC-MRT16 is the most recent version.  ABC-MRT16 is applicable to narrowband, wideband, superwideband, and fullband speech, whereas ABC-MRT is applicable to narrowband speech only.

For each input audio file, the ABC-MRT16 algorithm uses temporal correlations within articulation index bands and a model for attention to select one of six possible words from a list. The rate of successful word identification becomes the measure of speech intelligibility, as in the MRT.

ABC-MRT16 consumes a tiny fraction of the resources required by MRT testing.  ABC-MRT16 has been tested on a wide range of impaired speech recordings.  The Pearson correlation between ABC-MRT16 and MRT across 367 different conditions is above 0.95 and the RMS estimation error is below 7% of full scale.

ABC-MRT details are available in a paper presented at the IEEE 2013 Workshop on Applications of Signal Processing to Audio and Acoustics. Full details on ABC-MRT16 are given in a paper presented at the IEEE 2017 International Conference on Acoustics, Speech, and Signal Processing.

The ABC-MRT16 software package (for MATLAB© or Octave) is available by clicking on the link below the next paragraph. The 567 MB package provides ABC-MRT16 and ABC-MRT along with instructions for use, example scripts, data to run the demo script, and 1200 MRT source speech files to support exhaustive ABC-MRT testing.

The download contains software developed by NTIA. NTIA does not make any warranty of any kind, express, implied or statutory, including, without limitation, the implied warranty of merchantability, fitness for a particular purpose, non-infringement and data accuracy. NTIA does not warrant or make any representations regarding the use of the software or the results thereof, including but not limited to the correctness, accuracy, reliability or usefulness of the software or the results. You can use, copy, modify, and redistribute the NTIA-developed software upon your acceptance of these terms and conditions and upon your express agreement to provide appropriate acknowledgments of NTIA's ownership of and development of the software by keeping this exact text present in any copied or derivative works.

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