Institute for Telecommunication Sciences / Research / Audio Quality Research / 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. Some history and example applications are described here. 

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.

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