The following information is from a poster session given at The IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP '97), Munich Germany, 1997.
A Comparison of the New 2400 BPS MELP Federal Standard with other Standard Coders
M.A. Kohler
U.S. Department of Defense
Ft. Meade, MD
makohle@alpha.ncsc.mil
Introduction
Diagnostic Acceptability Measure (DAM)
Mean Opinion Score (MOS)
Degradation Mean
Opinion Score (DMOS)
Diagnostic Rhyme Test (DRT) -
Benign Conditions
Diagnostic Rhyme Test (DRT) - Harsh
Conditions
ARCON Communicability Exercise (ACE-95)
NRL Talker Recognizability Test (NTRT)
Complexity
Measures
Scores By Talker Gender
MOS Ranking
DMOS Ranking
DRT Ranking
ACE-95 Ranking
Diagnostic Information
References
Four Standard Coders Were Tested
 | Continuously Variable Slope Delta Modulation (CVSD)
| ||||
| Code Excited Linear Prediction (CELP)
| ||||
| Mixed Excitation Linear Prediction (MELP)
| ||||
| Linear Predictive Coding (LPC)
|
Five Measurements
| Quality
| ||||||
| Intelligibility
| ||||||
| Communicability
| ||||||
| Recognizability
| ||||||
| Complexity
|
Diagnostic Acceptability Measure
Two Conditions
| Quiet
| ||||
| Office
|
Mean Opinion Score
Six Conditions
| Quiet
| ||||||
| Quiet - H250
| ||||||
| 1% Random Bit Errors
| ||||||
| 0.5% Random Block Errors
| ||||||
| Office
| ||||||
| Mobile Command Environment
|
Degradation Mean Opinion Score
Five Conditions
| High Mobility Multi-Wheeled Vehicle
| ||||||
| E3A
| ||||||
| Automobile
| ||||||
| Single Tandem
| ||||||
| Double Tandem
|
Diagnostic Rhyme Test
Seven Benign Conditions
| Quiet
| ||||||
| Quiet-H250
| ||||||
| 1% Random Bit Errors
| ||||||
| 0.5% Random Block Errors
| ||||||
| P3C
| ||||||
| Mobile Command Environment
| ||||||
| Office
|
Diagnostic Rhyme Test
Eight Harsh Conditions
| Single Tandem
| ||||
| Double Tandem
| ||||
| Automobile
| ||||
| M2 Tank
| ||||
| High Mobility Multi-Wheeled Vehicle
| ||||
| F15 Fighter Jet
| ||||
| E3A
| ||||
| CH47 Helicopter
|
ARCON Communicability Exercise
Four Scenarios
Asymmetrical Scenarios Produced Eight Conditions
| Office <-> POTS <-> Quiet
| ||||
| E3A <-> JTIDS <-> MCE
| ||||
| Aircraft Carrier <-> HF <-> Office
| ||||
| HMMWV <-> Satellite <-> Quiet
|
NRL Talker Recognizability Test
Two Comparisons
| Unprocessed versus Processed |
| Processed versus Processed |
Complexity
Three Measurements
| Random Access Memory
| ||
| Read Only Memory
| ||
| Million Instructions Per Second
|
Scores By Talker Gender
| Diagnostic Acceptability Measure |
| Mean Opinion Score |
| Degradation Mean Opinion Score |
| Diagnostic Rhyme Test- Benign Conditions |
| Diagnostic Rhyme Test - Harsh Conditions |
| NRL Talker Recognizability Test |
Male Talker Score is Indicated to the Left of Each Symbol on Each Plot
Diagnostic Acceptability Measure Gender Scores
Two Conditions
| Quiet
| ||||
| Office
|
Male Talker Score is Indicated to the Left of Each Symbol
Top
of Presentation |
Top
of Gender Scores
Mean Opinion Score
Six Conditions
| Quiet
| ||||||
| Quiet - H250
| ||||||
| 1% Random Bit Errors
| ||||||
| 0.5% Random Block Errors
| ||||||
| Office
| ||||||
| Mobile Command Environment
|
Male Talker Score is Indicated to the Left of Each Symbol
Top
of Presentation |
Top
of Gender Scores
Degradation Mean Opinion Score
Five Conditions
| High Mobility Multi-Wheeled Vehicle
| ||||||
| E3A
| ||||||
| Automobile
| ||||||
| Single Tandem
| ||||||
| Double Tandem
|
Male Talker Score is Indicated to the Left of Each Symbol
Top
of Presentation |
Top
of Gender Scores
Diagnostic Rhyme Test
Seven Benign Conditions
| Quiet
| ||||||
| Quiet-H250
| ||||||
| 1% Random Bit Errors
| ||||||
| 0.5% Random Block Errors
| ||||||
| P3C
| ||||||
| Mobile Command Environment
| ||||||
| Office
|
Male Talker Score is Indicated to the Left of Each Symbol
Top
of Presentation |
Top
of Gender Scores
Diagnostic Rhyme Test
Eight Harsh Conditions
| Single Tandem
| ||||
| Double Tandem
| ||||
| Automobile
| ||||
| M2 Tank
| ||||
| High Mobility Multi-Wheeled Vehicle
| ||||
| F15 Fighter Jet
| ||||
| E3A
| ||||
| CH47 Helicopter
|
Male Talker Score is Indicated to the Left of Each Symbol
Top
of Presentation |
Top
of Gender Scores
NRL Talker Recognizability Test
Two Comparisons
| Unprocessed versus Processed |
| Processed versus Processed |
Male Talker Score is Indicated to the Left of Each Symbol
Top
of Presentation |
Top
of Gender Scores
Diagnostic Information
Diagnostic Acceptability Measure (DAM)
Elementary Perceptual Qualities (EPQs)
Signal
| Fluttering |
| Thin (HPF) |
| Harsh |
| Muffled |
| Interrupted |
| Nasal |
| Thin (LPF) |
| Babble |
Background
| Hissing |
| Rushing |
| Rumbling |
| Buzzing |
| Bubbling |
| Staticy |
| Chirping |
Diagnostic Rhyme Test (DRT)
Phonetic Factors
| Nasality (Grave/Acute) | ||||||
| Sibilation (Voiced/Unvoiced) | ||||||
| Compactness (Voiced/Unvoiced (Sustained/Interrupted)) | ||||||
| Voicing (Frictional/NonFrictional) | ||||||
| Graveness (Voiced/Unvoiced (Plosive/Nonplosive))
| ||||||
| Sustention (Voiced/Unvoiced)
|
Top
of Presentation |
Top
of Diagnostics
Top
of Presentation |
Top
of Diagnostics
References
[1] L.M. Supplee, R.P. Cohn, J.S. Collura, A.V. McCree, "MELP: The New
Federal Standard at 2400 bps," IEEE International Conference on
Acoustics, Speech, and Signal Processing, Munich, Germany, 1997.
[2]
M.A. Kohler, P. LaFollette, M.R. Bielefeld, "Criteria for the D.o.D. 2400
bps Vocoder Selection," IEEE International Conference on Acoustics,
Speech, and Signal Processing, Atlanta Georgia, USA, 1996.
[3]
J.P.Campbell, Jr., T.E. Tremain, and V.C. Welch, "The Federal Standard 1016
4800 bps CELP Voice Coder." Digital Signal Processing 1, no. 3 (1991):
145-155.
[4] "Analog to Digital Conversion of Voice by 2400 bit/second
Linear Predictive Coding," Federal Standard 1015, Nov. 1984.
[5] J.D.
Tardelli, E.W. Kreamer, "Vocoder Intelligibility and Quality Test Methods,"IEEE
International Conference on Acoustics, Speech, and Signal Processing,
Atlanta, Georgia, USA, 1996.
[6] P.D. Gatewood, P.A. LaFollette, "Host
Laboratory Functions for the D.o.D. 2400 bps Vocoder Selection Process,"IEEE
International Conference on Acoustics, Speech, and Signal Processing,
Atlanta, Georgia, USA, 1996.
[7] E.W. Kreamer, J.D. Tardelli, "Communicability
Testing for Vocoders,"IEEE International Conference on Acoustics,
Speech, and Signal Processing, Atlanta, Georgia, USA, 1996.
[8] A.
Scmidt-Nielsen, D.P. Brock, "Speaker Recognizability Testing for Voice
Coders," IEEE International Conference on Acoustics, Speech, and Signal
Processing, Atlanta, Georgia, USA, 1996.
[9] T.E. Tremain, M.A. Kohler, "Philosophy
and Goals of the D.o.D. 2400 bps Vocoder Selection Process," IEEE
International Conference on Acoustics, Speech, and Signal Processing,
Atlanta, Georgia, USA, 1996.
[10] M.R. Bielefeld, "1995 Test and
Evaluation Plan for the Selection of a New U.S. Government Standard Voice
Processor at 2,400 bps," MITRE Technical Report 96W0000029, August 1996.
[11]
V.C. Welch, T.E. Tremain, J.P. Campbell, Jr., "A Comparison of U.S.
Government Standard Voice Coders," IEEE Military Communications Conference,
Boston MA, 1989.
[12] W.D. Voiers, "Evaluating Processed Speech Using
the Diagnostic Rhyme Test," Speech Technology, Jan/Feb 1983.
[13] M.A.
Kohler, "Analysis of Performance and Complexity for Four Government
Standard Voice Coding Algorithms," NSA Technical Report, R22-002-96,
S-243,720.