1 Scope
2
References
3
Definitions
4
Abbreviations
5
Conventions
6
Recommended methods
6.1 Conversation-opinion tests
6.2 Listening-opinion tests
6.3 Interview and survey tests
6.4 Other tests
Annex A – Conversation-opinion tests
A.1 Test facilities
A.1.1 Physical conditions
A.1.2 Establishing the connection
A.1.3 Monitoring
A.2 Experiment design
A.3 Conversation task
A.4 Test procedure
A.4.1 Eligibility of subjects
A.4.2 Opinion scale
A.4.3 Instructions to subjects
A.4.4 Data collection
A.4.5 Treatment of results
Annex B – Listening tests – Absolute Category Rating (ACR)
B.1 Source recordings
B.1.1 Recording environment
B.1.2 Sending system
B.1.3
Recording system
B.1.4 Speech material
B.1.5 Recording procedure
B.1.6 Talkers
B.1.7 Speech levels
B.1.8 Calibration signal
B.2 Selection of circuit conditions
B.2.1 Speech input and listening levels
B.2.2 Talkers
B.2.3 Reference conditions
B.2.4 Other conditions
B.3 Design of experiment
B.4 Listening test procedure
B.4.1 Listening environment
B.4.2 Listening system
B.4.3 Listening level
B.4.4 Listeners
B.4.5
Opinion scales recommended by the ITU-T
B.4.6 Instructions to subjects
B.4.7 Statistical analysis and reporting of
results
Annex C – Quantal-Response Detectability Tests
Annex D –Degradation Category Rating (DCR) method
D.1 Introduction
D.2 Degradation Category Rating (DCR) procedure
D.2.1 Speech samples
D.2.2 Reference conditions
D.2.3 Stimulus presentation
D.2.4 Test
instructions
D.3 Statistical analysis
Annex E – Comparison Category Rating (CCR) method
E.1 Introduction
E.2 Quality reference
E.3 MNRU references
E.4 Presentation to listeners
E.5 Data analysis
Annex F – The threshold method for comparison of transmission
systems with a reference system
F.1 Introduction
F.2 Testing procedure
F.3 Presentation of signals
F.4 Speech sources
F.5 Listening environment
F.6 Listeners
F.7 Reliability
Bibliography