• Handbook – Practical procedures for subjective testing 2011
    • Foreword
    • Table of Contents
    • Section 1 – General
      • 1.0 General
      • 1.1 Comments on subjective methods used in the laboratory
      • 1.2 Utilization of the outcome of experiments
      • 1.3 ITU-T Recommendations
      • 1.4 The continuing need for subjective tests
      • 1.5 Laboratory tests versus field tests
      • 1.6 Recommended methods
        • 1.6.1 Conversational opinion tests
        • 1.6.2 Listening opinion tests
        • 1.6.3 Interview and survey tests
        • 1.6.4 Other subjective test methods
    • Section 2 – Test purpose
      • 2.0 Introduction
      • 2.1 Qualification
      • 2.2 Selection
      • 2.3 Characterization
      • 2.4 Verification
      • 2.5 Research
      • 2.6 Others
    • Section 3 – Experimental designs
      • 3.0 Introduction
      • 3.1 Steps to designing a subjective test
      • 3.2 Design elements and design principles
        • 3.2.1 Sources of variability (languages, talkers, speech material, subjects, ...)
        • 3.2.2 Factors - random or fixed effects
      • 3.3 Types of test designs
        • 3.3.1 Factorial design
        • 3.3.2 Balanced blocks experimental design
        • 3.3.3 Latin Square and related designs
        • 3.3.4 Graeco-Latin Square design
        • 3.3.5 Nested design
        • 3.3.6 Other designs
      • 3.4 Scales
        • 3.4.1 Nominal scale
        • 3.4.2 Ordinal scale
        • 3.4.3 Interval scale
        • 3.4.4 Ratio scale
    • Section 4 – Conversational opinion tests
      • 4.0 Introduction
      • 4.1 Test facilities
      • 4.2 Test design
      • 4.3 Conversation task
      • 4.4 Test procedure
        • 4.4.1 Selection of test subjects
        • 4.4.2 Subjective evaluation criteria and opinion scales
        • 4.4.3 Example instructions to subjects of the conversational test
        • 4.4.4 Data collection
        • 4.4.5 Data analysis and report of results
    • Section 5 – Listening opinion tests
      • 5.0 Introduction
      • 5.1 Database material
        • 5.1.1 Speech
        • 5.1.2 Noise database
        • 5.1.3 Processing for addition of noise and speech
      • 5.2 Reference systems
        • 5.2.1 Intermediate reference system
        • 5.2.2 Modified Intermediate Reference System
        • 5.2.3 Flat filtering systems
        • 5.2.4 Other filtering systems
      • 5.3 Collection of source material
        • 5.3.1 Recording environment
        • 5.3.2 Recording system
        • 5.3.3 Control of the speech/music data base
        • 5.3.4 Processing of the speech files
        • 5.3.5 Source/Processed speech file naming convention
      • 5.4 Listening test procedure
        • 5.4.1 Listening environment
        • 5.4.2 Listening system
        • 5.4.3 Listening level
        • 5.4.4 Eligibility of subjects
        • 5.4.5 Subjective evaluation criteria and Opinion scales
        • 5.4.6 Equivalence of opinion scales between languages
        • 5.4.7 Category judgement
        • 5.4.8 Instructions to subjects
    • Section 6 – Statistical analysis and reporting of results
      • 6.0 Introduction
      • 6.1 Basic concepts of statistics
        • 6.1.1 General principles of statistics
        • 6.1.2 Definitions
        • 6.1.3 Application in subjective tests
      • 6.2 Student t-tests
        • 6.2.1 Advantages and disadvantages
        • 6.2.2 Definitions
      • 6.3 Analysis of Variance
        • 6.3.1 Purpose and underlying assumptions
        • 6.3.2 Analysis
        • 6.3.3 Post hoc comparison of means
    • Section 7 – Experimental design for speech coder evaluations (controlling sources of error)
      • 7.0 Introduction
      • 7.1 Source material factors (recording procedures, talker factors)
      • 7.2 Laboratory factors
      • 7.3 Language factors
      • 7.4 Listener factors (selection and sampling, instructions and training)
      • 7.5 Time/order factors, balance factors (generation of randomization), test context
      • 7.6 Sequences/sessions duration
      • 7.7 Presentation of results
        • 7.7.1 Analysis tools
        • 7.7.2 Data collection
        • 7.7.3 GAL
    • Section 8 – Examples of Test plans/Results on coders
    • Annex A – Processing principles (Software Tool Library)
      • A.1 Scope
      • A.2 History
      • A.3 Motivation
      • A.4 Software tools to emulate transmission chains
      • A.5 Software tools to process references for subjective tests
      • A.6 Software tool for ITU-T speech and audio codecs specification and objective performance assessment
      • A.7 Using the STL for implementing processing associated with a test design
    • Annex B – Relationship between subjective and objective test methods
      • B.1 Recommendation ITU-T P.862
      • B.2 Perceptually Weighted Misclassification Counting
    • Appendix 1 – Misclassified active frame replacement procedure
    • Bibliography