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1. Speech Quality in Telephony. |
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1.2.1 Definition of Quality. |
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1.2.2 Speech Quality Assessment. |
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1.2.4 Speech Quality and Quality of Service. |
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2. Speech Quality Measurement Methods. |
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2.1.1 Utilitarian Methods. |
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2.1.2 Analytical Methods. |
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2.2 Instrumental Methods. |
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2.2.1 Signal-based Models. |
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2.2.2 Parameter-based Models. |
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2.3 Speech Quality Measurement Methods: Summary. |
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3. Quality Elements and Quality Features of VoIP. |
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3.1 Speech Transmission Using the Internet Protocol. |
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3.2 Overview of Quality Elements. |
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3.3 Quality Elements and Related Features. |
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3.3.1 Voice Activity Detection (VAD) . |
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3.3.11 Noise Suppression. |
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3.3.12 Linear Distortion and Wide-band Transmission. |
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3.5 Combined Elements and Combined Features. |
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3.6 Listening and Conversational Features. |
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3.8.1 From Quality Elements to Quality Features: The E-model and VoIP. |
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3.9 Quality Elements and Quality Features of VoIP: Summary. |
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4. Time-Varying Distortion: Quality Features and Modelling. |
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4.1 Microscopic Loss Behavior. |
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4.1.1 Random Packet Loss. |
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4.1.2 Dependent Packet Loss. |
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4.2 Macroscopic Loss Behavior. |
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4.2.1 Macroscopic Loss with Segments of Random Loss. |
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4.2.2 Macroscopic Loss with Segments of Dependent Loss. |
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4.4 Packet Loss and Combined Impairments. |
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4.4.1 Additivity and Multidimensional Feature Space. |
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4.4.2 Microscopic Loss Behavior: Random Packet Loss. |
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4.4.3 Macroscopic Loss Behavior: 3-state Markov Loss. |
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4.4.4 Model: Packet Loss and Combined Impairments. |
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4.5 Time-Varying Distortion: Summary. |
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5. Linear Distortion & Wideband Speech. |
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5.1 Wideband Speech: Improvement over Narrowband. |
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5.2 Bandpass-Filtered Speech. |
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5.2.2 Parametric Impairment Model. |
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6. Summary and Conclusions. |
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A. Aspects of Parametric Packet Loss Descriptions. |
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A.1 4-state Markov Chain: Sojourn in Bad and Good State. |
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A.2 Impact of other Quality Elements on Packet Loss. |
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A.2.1 Forward Error Correction (FEC). |
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A.2.2 Jitter and Jitter Buffer. |
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B. Simulation of Quality Elements. |
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B.1.1 Instrumental Verification. |
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B.3.1 Analog to ISDN Conversion. |
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B.3.3 IP Network Simulation. |
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B.3.4 Instrumental Verification. |
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B.4 Wideband Transmission. |
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B.5.2 Wideband Handset and Hifi Phone. |
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B.5.4 Hands-Free Terminals (HFTs) . |
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B.7 Simulation of Quality Elements: Summary. |
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C.1 Transmission Bandpass. |
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D. Test Data Normalization and Transformation. |
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D.2 Method According to ITU-T Rec. P.833. |
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D.3 Linear Transformation. |
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F. Interactive Short Conversation Test Scenarios (iSCTs). |
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G. Auditory Test Settings and Results. |
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G.2 2-State Markov Loss: LOT. |
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G.3.4 Details on Selected Results. |
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G.4 3-State Markov Loss: CT. |
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G.4.2 Test Procedure and Test Subjects. |
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G.4.3 Details on Selected Results. |
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G.5 Speech Sound Quality and Content. |
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H.1 Time-Varying Distortions. |
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H.1.1 Macroscopic Loss Behavior. |
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