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OPTICOM OPERA - V 3.5 User Manual

Objective perceptual analyzer
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  • Page 1 User Manual Version 3.5...
  • Page 2 C O N T E N T S Document Version as of 20 Dez. 02...

  • Page 3: Table Of Contents

    C O N T E N T S Contents Software License Agreement and Limitations ........1 General .......................... 1 Complaints Concerning Defects....................1 Software License ........................1 Limitations, Warranty, Liability ....................2 Applicable law and Place of Jurisdiction..................4 Preface ..................... 5 How this Manual is Organized ....................
  • Page 4 C O N T E N T S Getting to Know the OPERA™ Framework......29 General Concept ..................... 29 Data Acquisition Using OptiCall™..............30 4.2.1 POTS Telephony Interfaces..................30 4.2.2 Audio Interfaces ....................33 4.2.3 The OptiCall™ Program..................40 The OPERA™ Framework ................54 4.3.1 The Underlying Generic Algorithm Model .............54 4.3.2...
  • Page 5 C O N T E N T S Telephony Band Voice Quality Testing ........ 117 What To Know About Testing Telephony Band Voice Quality ....... 117 Reference Files for Voice Quality Testing and Echo Measurements ....118 PSQM as an Example for Perception Based Measurement Algorithms ..119 PSQM or PESQ, which one shall I use? ............
  • Page 6 C O N T E N T S Technical Specifications ............177 Software ......................177 Framework ..............................177 PEAQ Algorithm ............................178 PSQM Algorithm ............................179 PESQ Algorithm ............................180 Echo Algorithm ............................181 Hardware....................... 181 POTS Telephony Board ..........................181 Audio Interface Option (LynxONE) ......................182 Audio Interface Option (Digigram) ......................183 OPERA Workstation...........................183 OPERA Portable ............................183 References.....................185...

  • Page 7: Software License Agreement And Limitations

    Software License The accompanying software to this OPTICOM product is licensed, not sold. OPTICOM hereby grants the user of the OPERA Software (herewith referred to as 'Licensee') with respect to the Licensed Patents,...

  • Page 8: Limitations, Warranty, Liability

    Limitations, Warranty , Liability 1. OPTICOM shall retain all right, title and interest in and to the OPERA Software, subject to the license granted. Licensee shall be entitled to establish all proprietary rights for itself in the intellectual property represented by enhancements and new features, created by Licensee, whether in the nature of trade secrets, copyrights or patent rights or other rights.
  • Page 9 In case of a loss of data, OPTICOM shall only be liable for the expenses required to reconstruct the lost data using backup files duly created in regular intervals.

  • Page 10: Applicable Law And Place Of Jurisdiction

    S O F T W A R E L I C E N S E A G R E E M E N T A N D L I M I T A T I O N S In the event that any afore-mentioned terms or conditions are found to be invalid, unlawful or unenforceable to any extent, this shall not effect any other terms and conditions agreed herein.

  • Page 11: Preface

    P R E F A C E PREFACE A Brief How-to Guide to this Manual and How to Get More Information and Support. e are delighted to welcome you as our new customer. As you might know from our company vision - quality is our business Especially when it comes to signal quality of speech and wide band audio signals.

  • Page 12: Conventions Used In This Manual

    P R E F A C E a summary of the functionalities, which you will always need, regardless of specific measurement algorithms. The next two Chapters, Chapter 5, "Wide Band Audio Quality Testing" , and Chapter 6, "Telephony Band Voice Quality Testing" , deal with the specific measurement setups and methods for both principle applications.

  • Page 13: Further Information And Support

    In case you would encounter a bug or a problem, which is not yet listed on the support section of our web page, please make sure to contact the OPTICOM support with a detailed bug report.
  • Page 14 P R E F A C E...

  • Page 15: Introduction

    C H A P T E R I N T R O D U C T I O N Chapter 1 INTRODUCTION An Introduction to the OPERA™ Measurement System and the OPERA™ Product Family. À fter reading this chapter you will be familiar with the basic ideas and the concept behind this tool.
  • Page 16 C H A P T E R I N T R O D U C T I O N OPERA’s flexible scalability may range from a single stand alone tester up to powerful network-wide setups with distributed systems sharing information over TCP/IP.

  • Page 17: Getting To Know The Opera™ Product Family

    C H A P T E R I N T R O D U C T I O N 1.2 Getting to Know the OPERA™ Product Family 1.2.1 OPERA™ Measurement System The OPERA™ Measurement System comprises both hardware requirements and software.

  • Page 18: Opera™ Software Suite

    C H A P T E R I N T R O D U C T I O N measurements, the corresponding required interfaces and cables will be provided. Of course assessing prerecorded files is possible too. For a detailed description of the delivery , please refer to Section 3.2.2.

  • Page 19: Test Methodology

    C H A P T E R T E S T M E T H O D O L O G Y ? Chapter 2 TEST METHODOLOGY Essential Knowledge about Perceptual Measurements and a Guidepost to the Correct Measurement Method. his chapter describes listening test methods which are modeled by the OPERA™...
  • Page 20 C H A P T E R W H I C H M E A S U R E M E N T N E E D ? Impairment Grade Excellent Good Fair Poor Table 2.1: The ITU-T five-grade impairment scale Based on these test conditions a population of typically 20 to 50 test subjects will be presented with an identical series of speech fragments.

  • Page 21: Advanced Audio Measurements Employing "Perceptual Modeling

    MUSHRA is expected to become adopted as an international recommendation by the ITU working party 10-11Q. As soon as more experience has been gained, OPTICOM will provide its customers with more information at www.peaq.org 2.2 Advanced Audio Measurements...

  • Page 22: International Standardization

    C H A P T E R W H I C H M E A S U R E M E N T N E E D ? the "output" signal of the codec). First, the algorithms process an ear model for the reference and the test signal, in order to calculate an estimate for the audible signal components.
  • Page 23 C H A P T E R T E S T M E T H O D O L O G Y ? Since P.861 was mainly developed for application to isolated speech codecs in ITU-T P.862 mobile networks, a new measure was required to cope with real networks as well as packet based transmission.

  • Page 24: Which "Measurement" For Which "Application

    C H A P T E R W H I C H M E A S U R E M E N T N E E D ? mentioned earlier, the threshold between both worlds - broadcasting and telecommunication - is floating due to the steadily attempt to further reduce the bit rates by more efficient coding schemes.
  • Page 25 C H A P T E R T E S T M E T H O D O L O G Y ? (device under test) ORIGINAL TEST BS.1116 Setup wide band audio: YES comparison with reference: YES PEAQ Figure 2.3: Illustration of the principle of BS.1116 (device under test) ORIGINAL TEST...

  • Page 26: Selection Of The Reference File

    C H A P T E R W H I C H M E A S U R E M E N T N E E D ? 2.5 Selection of the Reference File As a rule of thumb, the reference file should be a signal that comes as close as possible to the kind of signal which shall be applied to the device under test in real life.
  • Page 27 C H A P T E R T E S T M E T H O D O L O G Y ? based measurement algorithms assume that any audible difference between the two input signals is a distortion, and by definition the "enhanced" signal will sound different than the unprocessed signal.
  • Page 28 C H A P T E R W H I C H M E A S U R E M E N T N E E D ?

  • Page 29: Installation And Setup

    C H A P T E R I N S T A L L A T I O N A N D S E T U P Chapter 3 INSTALLATION AND SETUP Using OPERA™ for the first time. lease review this chapter before you continue. Checking the complete contents of your OPERA™...

  • Page 30: Installation And Setup

    In order to adjust this parameter, open regedit and look for the key: HKEY_LOCAL_MACHINE\Software\Opticom\Opera\Memory\MemoryReserved A good value for this key is 130 000 000 on a machine with 256MB RAM. The parameter defines how much of the physical memory is left free by OPERA.
  • Page 31 Note: Please do not upgrade the operating system or the service pack without consulting OPTICOM. To setup the OPERA™ workstation system, place the main unit on a solid and dry surface. Connect the monitor, mouse, keyboard and the power cables to the back of the main unit.

  • Page 32: Portable Pc Version

    C H A P T E R I N S T A L L A T I O N A N D S E T U P All OPERA™ systems come with an ethernet port that may be used to connect IP / LAN Concerns the system to a data network.
  • Page 33 Note: Please do not upgrade the operating system or the service pack without consulting OPTICOM. To setup the OPERA™ portable system, place the main unit on a solid and dry surface. Attach the dongle to the parallel interface port of the computer, if it is not yet there, connect the power cable to the side panel of the main unit and switch on the system.
  • Page 34 C H A P T E R I N S T A L L A T I O N A N D S E T U P...

  • Page 35: Getting To Know The Opera™ Framework

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Chapter 4 GETTING TO KNOW THE OPERA™...

  • Page 36: Data Acquisition Using Opticall

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K side for analysis. In the expert view (see 4.2.3 The OptiCall™ Program) the set- up where the test file is sent in the reverse direction can be selected.
  • Page 37 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.1: POTS Telephony board end bracket Note: On the end bracket of the POTS telephony interface board, the following connectors are currently not used: E&M power supply,...
  • Page 38 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.2: Splitter cable used to attach two POTS lines to one OPERA port. Figure 4.3 : The configuration and labelling of the adapter wires Monitoring...

  • Page 39: Audio Interfaces

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K c:\Programme\QXCustomParameters1999-4 In this folder a number of batch files is stored which are all named Setxxxx.bat, where xxxx stands for a specific country or switch.
  • Page 40 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.4: Layout and labelling of the multi cable connector. In addition to the connectors for analog signals there are five XLR connectors for digital signals, two inputs ("AES-EBU In1"...
  • Page 41 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Note: The faders of the audio mixer take effect on the gain of the digital side of the A/D converter.
  • Page 42 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.6: Block diagram of the Digigram audio board. LynxONE Audio OPERA™...
  • Page 43 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K The nominal analog signal levels are compatible with either professional or consumer equipment.
  • Page 44 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.8: LynxONE mixer setting for an analog reference signal Figure 4.9: LynxONE mixer setting for an analog test signal Figure 4.8 and Figure 4.9 represent the typical settings for a measurement input signals.
  • Page 45 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.10 and Figure 4.11 represent the typical settings for a measurement with input signals.

  • Page 46: The Opticall™ Program

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K To achieve the highest possible accuracy, all recordings from the LynxONE LynxONE Audio interfaces will be made in stereo and at 24bit resolution.
  • Page 47 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K remote system whenever the name in the edit field changes and click to somewhere outside of that field.
  • Page 48 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.12 . The final filenames that are recorded to the harddisk will start with this root file name and a unique identifier for the line interface on which the data were recorded, plus the extension ".wav"...
  • Page 49 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K interface it must be set to digital. Also take care, that on the playing side the digital interfaces are neither selected as the monitoring source, nor as the monitoring output.
  • Page 50 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.14: Typical audio setup using two audio interfaces. Telephony Standard View OptiCall™...
  • Page 51 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K the line interfaces, and after a call has completed, the system will automatically wait for the next call.
  • Page 52 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Note: By using OptiCall – Telephony Standard View, it is always the terminating side of a call that is talking.
  • Page 53 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K c:\temp\demo—line4.wav Data recorded at the originating side (degraded speech signal) c:\temp\demo—line6.wav Data recorded at the terminating side (Echo...
  • Page 54 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.18 shows the OptiCall™ window after Termination has been selected.
  • Page 55 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Note: mode is not available for audio interfaces! Terminate all As you can see in Figure 4.19, the list boxes for selection of the originating and the terminating interfaces are disabled now.
  • Page 56 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.20: OptiCall™ Expert View While in the Telephony Standard View, the termination side was always sending the speech file.
  • Page 57 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K be used. The shortest possible delay is in the rage of one to two seconds, depending on the load of the system and the length of the files.
  • Page 58 This offset is generally compensated automatically by the system. Since these delays may vary with different board driver versions, please contact OPTICOM if your results tend to show such an offset. OptiCall™ Command line Parameters To allow for automated execution from scripts, OptiCall™...
  • Page 59 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K interface -TerminatingLine <0|..N> Index of the terminating interface -Player <Bitmask>...

  • Page 60: The Opera™ Framework

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K • If a POTS interface is selected for either the terminating or the originating side, you must use an 8kHz, 8Bit G.711 mono reference file.

  • Page 61: The Structure Of The Opera™ Framework

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K The final goal instead is to derive a quality measure, consisting of a single number that indicates the audibility of the distortions present in the signal under test.
  • Page 62 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K The following step "Delay and Gain Compensation" is as complex as some Delay and Gain perceptual algorithms are themselves, especially if a robust and computational Compensation...

  • Page 63: Basic Operation

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Algorithms are just Consequently, the idea behind the framework is to share these parts between plug-ins various measurement algorithms.

  • Page 64: How To Select A Measurement Algorithm

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K The core of the main window is the two diagram panes that will display the Diagram panes results of your measurements.
  • Page 65 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Note: Depending on which algorithms are actually installed the dialog may look a bit different than Figure 4.25 The order of the algorithms may be different as well.

  • Page 66: How To Start A Measurement

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Note: For consistency reasons the diagrams and/or the history buffer will be cleared when changing the algorithm or its parameters.
  • Page 67 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Browse to bring up a standard windows file select dialog box. If the file type is valid, the file format parameters in the line below the edit box will be visible.
  • Page 68 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K and the test signal in the right channel of a file. Figure 4.29 shows a screen dump of this wizard step.
  • Page 69 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.30: Input Mapping Measurement Setup Wizard Step 4, Delay compensation and signal preprocessing In this wizard step various parameters of the signal preprocessing applied to...
  • Page 70 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.31: Signal Preprocessing Options In the group box Coarse delay compensation choose the way in which the...
  • Page 71 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K below) will be activated. Please note: these functions are disabled when file- based measurements are performed.
  • Page 72 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K The right field at the bottom of the dialog window shown in Figure 4.31 Static Delay of shows an edit control titled Static Delay of Reference Signal.
  • Page 73 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K τ auto τ τ tracking static τ...

  • Page 74: How To Display The Results

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Reset Averaged Note: Values Many measurement result values in OPERA™...
  • Page 75 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.38: Selecting the diagram type from the pop-up menu 2.
  • Page 76 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.39: Select Result Type Window Now highlight the radio button next to Timesignals, and press Next.
  • Page 77 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.40: Select Signal Window Pressing Next again leads to the next step, the Result Style dialog (see Figure 4.41).
  • Page 78 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.41: Result Style Window After this last step click on Finish and the selected diagram will appear in the diagram pane.

  • Page 79: Setting Markers In Diagrams

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Displayed Values Interpretation Time: The time when the measurement has been finished.

  • Page 80: Logging Results

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K 4.4.6 Logging Results After a measurement has been performed, the final results that were achieved, can be logged to a text file.

  • Page 81: Measuring Only Parts Of The Input Files

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Figure 4.44: Measurement Setup Wizard Step 1. Selection of the Soundboard Figure 4.45: Format dialog 4.4.8 Measuring only parts of the Input Files OPERA™...

  • Page 82: Printing

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K after respectively. Finally choose whether the start and end time should be related to the beginning of the reference or to the beginning of the test file.

  • Page 83: Summary Of The Menu Options

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K While the command Edit|Copy will copy the diagram as it is displayed in the Edit|Copy OPERA™...
  • Page 84 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K This menu option currentlyhas no function. Edit|Cut This menu option currentlyhas no function.
  • Page 85 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K View|Clear all Markers Removes all markers from the current diagram Measurement Menu Measurement|Algorithm Parameters...
  • Page 86 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K Help|About OPERA... Opens the About box that contains license information, the version number and the copyrights.

  • Page 87: Performing Measurements From Batch Files

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K 4.5 Performing Measurements From Batch Files When performing measurements on a huge number of input files it is much easier to start your OPERA™...

  • Page 88: How To Use A Configuration File

    C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K the right channel of the reference signal (0=left, 1=right) ChannelTestLeft <0 | 1>...

  • Page 89: Example Runpsqm.bat

    ************************************************** echo ***** RunPSQM V1.0 (c) OPTICOM, 1998 echo ************************************************** echo. pushd echo *** TODO: change working dir according to where OPERA.exe is! rem c: rem cd "\programme\opera"...
  • Page 90 C H A P T E R G E T T I N G K N O W T H E O P E R A ™ F R A M E W O R K...

  • Page 91: Wide Band Audio Quality Testing

    C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Chapter 5 WIDE BAND AUDIO QUALITY TESTING Measuring the Perceived Audio Quality (PEAQ) of e.g.

  • Page 92: Reference Files For Wideband Audio Measurements

    C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G The basic concept for making objective measurements with the recommended method is illustrated in Figure 5.1 below.

  • Page 93: Fundamentals Of The Peaq Measurement Algorithm

    C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Sources: Offline Sound Files Recorder (always) PEAQ Audio Online...

  • Page 94: Basic Version

    C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G the Advanced version is hidden in the respective ear models and the set of MOVs used.

  • Page 95: Advanced Version

    C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G temporal resolution is in the same range as the timing of any backward masking effects, which therefore can not be modelled.

  • Page 96: Using Peaq

    C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G In comparison to the FFT based "Basic" approach, the temporal resolution is improved, thus allowing for a better simulation of temporal effects, at the cost of frequency resolution and computational complexity.

  • Page 97: Opera Software Suite - Peaq

    C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G 5.5.1 OPERA Software Suite - PEAQ When using the OPERA Software Suite, there is no access to audio interfaces provided.

  • Page 98: Diagram Types, Peaq Basic

    C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Figure 5.5: PEAQ algorithm specific properties 5.5.4 Diagram Types, PEAQ Basic Chapter 4 showed how to select a measurement algorithm and how to start a measurement.
  • Page 99 C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Chapter 4. However, there are some different parameters. Table 5.3 explains the shown settings and their meaning.
  • Page 100 C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Figure 5.8: Select Signal Window Pressing Next again leads to the next step, the Result Style dialog (see Figure 5.9).
  • Page 101 C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Figure 5.9: Result Style Window After this last step click on Finish and the selected diagram will appear in the diagram pane as shown in Figure 5.10.
  • Page 102 C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Figure 5.11: Select Signal Dialog Figure 5.12: Result Style Dialog Figure 5.13: The Spectra diagram...
  • Page 103 C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Excitation The excitation diagram displays the internal representation (see Section 2.2) of a signal.
  • Page 104 C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Figure 5.15: Excitation result styles Figure 5.16: The Excitations diagram The measurement scheme NMR (Noise-to-Mask Ratio) [BRAN87] evaluates the level-difference between the masked threshold (the maximum level of a not audible error) and the actual noise (error) signal.
  • Page 105 C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Figure 5.17: Select Signal window of the NMR diagram type Figure 5.18: The NMR diagram Masked Threshold A signal that is clearly audible can be completely inaudible in the presence of...
  • Page 106 C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Figure 5.19: Signal Select window of the Masked Threshold Figure 5.20: The Masked Threshold diagram Loudness The perceived loudness of audio signals depends on their frequency, their...
  • Page 107 C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Figure 5.21: Select Signal window of the loudness diagram type Figure 5.22: The Loudness result styles Figure 5.23: The Loudness diagram...
  • Page 108 C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Model Output Variables and ODG The screen shot in Figure 5.24 shows the Model Output Variables (MOVs) as they are defined by BS.1387.
  • Page 109 C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G algorithm. The ODG is the output value from the objective measurement method that corresponds to the SDG (see Section 2.1) in the subjective domain.
  • Page 110 C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Figure 5.26: The ODG vs. Time diagram NMR vs.

  • Page 111: Diagram Types, Peaq Advanced

    C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G PEAQ Basic Final Results Figure 5.29 shows the final results diagram for the Basic version of PEAQ. This screen is a summary of the results obtained for the entire measurement sequence, from the start point to the end point.
  • Page 112 C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Modulation The Modulation diagram shows the modulation of the reference and the test signal over a bark scale.

  • Page 113: Command Line Arguments

    C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Objective Difference Grade (ODG) and DI The last two bars in the diagram shown in Figure 5.31 are the Distortion Index (DI) and the final Objective Difference Grade (ODG).

  • Page 114: Example 1: Online Monitoring

    C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G 5.6.1 Example 1: Online Monitoring Assuming we have the reference and the test signal needing to be assessed in a digital format, e.g.
  • Page 115 C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Figure 5.33: Input Mapping Wizard step Figure 5.33 shows the correct settings of the Input Mapping dialog.
  • Page 116 C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G Figure 5.35: The Signal Preprocessing dialog of the Measurement Setup Wizard Figure 5.36: View on a real time measurement result As described in Chapter 4, the delay between the reference and the test signal is checked permanently in Normal Mode.

  • Page 117: Example 2: Stand Alone Testing

    C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G The Snap Again toolbar button to the right of the Freeze Delay button is disabled at the moment since our measurement is running in the Normal mode of the Automatic Delay Compensation.
  • Page 118 C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G signal and the signal of Input 2 as the test signal. This is done in the mapping window shown in Figure 5.40.

  • Page 119: Example 3: Measurements From A Batch File

    C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G After pressing the Finish button, the delay is computed, which might take some seconds.
  • Page 120 If it exists already results are appended to it, otherwise it will be newly created. echo ************************************************** echo ***** RunPeaqBasic V1.0 (c) OPTICOM, 1999 echo ************************************************** echo. pushd cd %1 Opera -Exec -Algorithm Name=PEAQ -Input Inp=0 File=%2 Inp=1 File=%3 -Mux InpRefLeft=0 ChannelRefLeft=0 InpRefRight=0...
  • Page 121 Outputfile: Results are stored in this file. If it exists already results are appended to it, otherwise it will be newly created. echo ****************************************************** echo ***** ConfPeaqBasic V1.0 (c) OPTICOM, 1999 echo ****************************************************** echo. @echo on call RunPeaqBasic %1 %2\Conformance-BS.1387\arefsna.wav %2\Conformance-BS.1387\acodsna.wav %3 call RunPeaqBasic %1 %2\Conformance-BS.1387\breftri.wav...

  • Page 122: More Examples

    C H A P T E R W I D E B A N D A U D I O Q U A L I T Y T E S T I N G call RunPeaqBasic %1 %2\Conformance-BS.1387\hrefstr.wav %2\Conformance-BS.1387\hcodstr.wav %3 call RunPeaqBasic %1 %2\Conformance-BS.1387\irefsna.wav %2\Conformance-BS.1387\icodsna.wav %3 call RunPeaqBasic %1 %2\Conformance-BS.1387\krefsme.wav...

  • Page 123: Telephony Band Voice Quality Testing

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Chapter 6 TELEPHONY BAND VOICE QUALITY TESTING Applying the Perceptual Speech Quality Measure...

  • Page 124: Reference Files For Voice Quality Testing And Echo Measurements

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G weakness of PSQM by extending the algorithm with a time alignment algorithm that can handle varying delays as they show up on packet oriented networks.

  • Page 125: Psqm As An Example For Perception Based Measurement Algorithms

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G DefaultRefFileMixed.wav different languages.

  • Page 126: Psqm Or Pesq, Which One Shall I Use

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G As depicted in Figure 6.2, the quality of the coded speech is judged on the basis of differences in the internal representation.

  • Page 127: Psqm Measurement

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Note: Never compare: •...
  • Page 128 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G y [n] x [n] Hanning window Hanning window...

  • Page 129: Signal Acquisition

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G accompanied cultural differences. For example, a noisy floor may be more annoying if there are more silent intervals during a telephone conversation.

  • Page 130: Psqm Algorithm Properties

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G 6.5.3 PSQM Algorithm Properties PSQM always simulates a listening test .
  • Page 131 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G show either framewise values (Timesignals, Spectra, Excitation), values averaged since the start of the measurement (Raw PSQM, MOS etc, MOS vs.
  • Page 132 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.7: Display of the current measurement settings of the PSQM algorithm Timesignals To choose this diagram type highlight the radio button next to Timesignals, and press Next.
  • Page 133 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Pressing Next again leads to the next step, the Result Style dialog (see Figure 6.9.
  • Page 134 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.11 shows the signal select wizard step for the spectra diagrams. Spectra Select the spectra of the reference signal, the test signal or the difference between the reference spectrum and the test spectrum.
  • Page 135 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.12: Result Style Dialog The resulting diagram is as shown in Figure 6.13.
  • Page 136 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.14: Select Signal Window for the excitation diagram type Figure 6.15 shows the resulting view off the Excitation diagram.
  • Page 137 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.16: The Raw PSQM diagram In PSQM, the silent intervals are taken into account using a weighting factor that depends on the context of subjective experiments, i.e.
  • Page 138 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.17: The diagram type MOS etc. Model Output Variable (MOV) Interpretation Silence...
  • Page 139 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G P.861 is not taken into account. To know the result at the stop point, Refer to the "Final Result"...

  • Page 140: Command Line Arguments

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.19: The PSQM Final Result diagram type 6.5.5 Command Line Arguments In addition to the command line arguments described in Chapter 4 specific commands will be described in this section.

  • Page 141: Common Mistakes

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Keyword Add.
  • Page 142 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G...

  • Page 143: Pesq Measurement And Vad Measurement

    It handled the larger distortions well, as they are caused by e.g. burst errors, but still had significant problems with the compensation of the varying delay. A Delay Tracking Feature has been added by OPTICOM in it’s OPERA™ system that implemented an easy way to solve the varying delay issue in most cases, without loosing the option of realtime operation.

  • Page 144: Advantage Of Using Pesq Instead Of Psqm

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G 6.6.1 Advantage of using PESQ instead of PSQM One of the major advantages of PESQ over PSQM(+) is, that it contains a real good time alignment algorithm, which is capable of handling varying delays.
  • Page 145 This mapping was submitted to the ITU-T SG12 with the intention of extending P.862 by an annex or appendix. SG12 however clearly rejected this proposal, and we, OPTICOM are fully in line with this rejection for the following reasons: •...
  • Page 146 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Delay and Delay As soon as a signal is processed by any piece of equipment, it will be slightly Jitter (Latency) delayed.
  • Page 147 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Within OPERA the Waveforms of the signals before, as well as after the time Waveforms alignment can be shown.
  • Page 148 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Loudness The loudness is a more psycho-acoustic view of the signal levels.

  • Page 149: Using Pesq

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Clipping. HOT can be assessed by a frequency analysis of the received signal. As long as the reference sine tone is detected in the received signal, the VAD is open.

  • Page 150: Diagram Types

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G • Due to the complex and iterative time alignment algorithm, the data are all processed in one frame.
  • Page 151 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.22: Waveform and VAD Parameters diagram.
  • Page 152 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G For a more detailed analysis of delay variations refer to the Delay vs. Time Diagram and the Delay Histogram.
  • Page 153 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.26: Delay vs. Time diagram Figure 6.27 shows another view of the delay measurement.

  • Page 154: Command Line Arguments

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.28: PESQ Gain Variation diagram 6.6.5 Command Line Arguments PESQ currently requires no algorithm specific command line switches.

  • Page 155: Interpretation Of Echo Parameters

    Figure 6.30 clearly shows there are two kinds of sources that signals can be obtained from. In all OPERA™ versions files can be assessed. When working with the OPERA system version including a POTS telephony board or the audio interface option, OPTICOM's signal acquisition software OptiCall™ can be used which is described in detail in chapter 4.

  • Page 156: Echo Algorithm Properties

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Phone Sources : (if voiceboard included )

  • Page 157: Diagram Types

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.32: The signal preprocessing dialog 6.7.6 Diagram Types Chapter 4 explained how to select a measurement algorithm and how to start a measurement.
  • Page 158 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G To the right of each diagram, some general information about the current Display of the measurement settings is shown in a text block (see Figure 6.34).
  • Page 159 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.35: Select Signal Window Pressing Next again leads to the next step, the Result Style dialog (see Figure 6.36).
  • Page 160 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.36: Result Style Window After this last step you may click on Finish and the selected diagram will appear in the diagram pane as shown in Figure 6.37.
  • Page 161 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.38: Display of the ERL diagram type Result Summary When choosing this diagram type, the diagram will display several result values of the echo measurement, as shown in Figure 6.39.

  • Page 162: Command Line Arguments

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G 6.7.7 Command Line Arguments In addition to the command line arguments described in Chapter 4 there is one specific command for the Echo algorithm.

  • Page 163: Measurement Examples

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G 6.8 Measurement Examples For an inexperienced user of the OPERA™...
  • Page 164 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G band) filter characteristic, Hoth noise of 45 dB(SPL), a listening level of 101 dB(SPL) and an upper frequency of 4 kHz.
  • Page 165 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.42: First step of the Measurement Setup Wizard As the second input signal, select the stored file whose filename contains "- Line0", in this example "D:\test\050700-Line0.wav"...
  • Page 166 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.43: Second step of the Measurement Setup Wizard After clicking on the Next button, we will get to the Signal Preprocessing dialog where the Automatic Delay Compensation function, the Static Gain Compensation function and the Remove DC from Signals option (see Figure...
  • Page 167 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.44: Signal Preprocessing dialog of the Measurement Setup Wizard Figure 6.45: Resulting view on the measurement results...
  • Page 168 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G At this time an echo measurement will be performed. Therefore the Echo Using the Echo algorithm from the Menu Measurement|Algorithm Parameters ...
  • Page 169 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.47: First step of the Measurement Setup Wizard Figure 6.48: Second step of the Measurement Setup Wizard...
  • Page 170 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G Figure 6.49: Settings in the Signal Preprocessing Dialog When clicking on the Finish button in the Signal Preprocessing Dialog, the echo is measured.

  • Page 171: Example 2: Measurements From A Batch File

    Outputfile: Results are stored in this file. If it already exists, results are appended to it, otherwise it will be newly created. echo ************************************************** echo ***** RunPSQM V2.0 (c) OPTICOM, 2000 echo ************************************************** echo. pushd echo *** TODO: change working dir according to where echo OPERA.exe is! echo ...
  • Page 172 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G First, there are no PSQM algorithm properties defined. This means that standard values are used as recommended by ITU-T P.861.

  • Page 173: More Examples

    C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G 6.8.3 More Examples ... More example setups, especially some more exotic applications can be found in our paper "OPERA Application Notes"...
  • Page 174 C H A P T E R T E L E P H O N Y B A N D V O I C E Q U A L I T Y T E S T I N G...

  • Page 175: Automation And Programming

    C H A P T E R A U T O M A T I O N A N D P R O G R A M M I N G Chapter 7 AUTOMATION AND PROGRAMMING 7.1 General This is primarily a summary of the previous chapters on using OPERA from the commandline.

  • Page 176: Parameters Common To All Algorithms

    C H A P T E R A U T O M A T I O N A N D P R O G R A M M I N G 7.2.2 Parameters common to all Algorithms Below the syntax of the command line parameters is described. For all parameters inside a command section (i.e.

  • Page 177: How To Use A Configuration File

    C H A P T E R A U T O M A T I O N A N D P R O G R A M M I N G -Signal StaticGainOn Switch the static gain compensation on InvertTestSignal Invert the test signal AutoInvertTestSig Automatically invert the test...

  • Page 178: Parameters Specific To The Measurement Algorithms

    C H A P T E R A U T O M A T I O N A N D P R O G R A M M I N G 7.2.4 Parameters Specific to the Measurement Algorithms The current PEAQ implementation provides several algorithm specific Parameters Specific command line parameters to: to the PEAQ...

  • Page 179: Parameters Specific To Opticall

    C H A P T E R A U T O M A T I O N A N D P R O G R A M M I N G Headphones Listening condition: Headphones HeadphonesDiff Listening condition: Headphones (diffuse field) Speakers Listening condition:...
  • Page 180 C H A P T E R A U T O M A T I O N A N D P R O G R A M M I N G -DelayBetweenRecordings <xxx> Wait xxx seconds between two data acquisition phases during one call.

  • Page 181: Example Runpsqm.bat

    ************************************************** echo ***** RunPSQM V1.0 (c) OPTICOM, 1998 echo ************************************************** echo. echo ... Processing file %1 Opera -Exec -Algorithm Name=PSQM -Input Inp=0 File=%1 Inp=1 File=%2 -Mux InpRefLeft=0 ChannelRefLeft=0 InpTestLeft=1...
  • Page 182 C H A P T E R A U T O M A T I O N A N D P R O G R A M M I N G Note: Although this example was mainly written for the purpose of bulk call testing, it can be easily adapted to simple calls or repeated calls.

  • Page 183: Technical Specifications

    C H A P T E R T E C H N I C A L S P E C I F I C A T I O N S Chapter 8 TECHNICAL SPECIFICATIONS 8.1 Software Framework Sound File Formats: WAVE-files containing: •...

  • Page 184: Peaq Algorithm

    C H A P T E R T E C H N I C A L S P E C I F I C A T I O N S PEAQ Algorithm General: Algorithm: Based on standard ITU-R BS.1387, Basic model Sample rates: 48 kHz (according to recommendation ITU-R BS.1387) In addition to BS.1387, the current OPERA™...

  • Page 185: Psqm Algorithm

    C H A P T E R T E C H N I C A L S P E C I F I C A T I O N S • Relative fraction of frames for which at last one frequency band contains a significant noise component (RDF) •...

  • Page 186: Pesq Algorithm

    C H A P T E R T E C H N I C A L S P E C I F I C A T I O N S • PSQM value of the silent intervals (PSQM-Silence) • Mean Opinion Score (MOS) according to P.861, silence weight = 0.0 (OMOS-W0) •...

  • Page 187: Echo Algorithm

    C H A P T E R T E C H N I C A L S P E C I F I C A T I O N S Echo Algorithm General: Maximum echo delay: 1000 ms Frame size: 16 ms at 8 kHz Averaging window size: 800 ms at 8 kHz...

  • Page 188: Audio Interface Option (Lynxone)

    C H A P T E R T E C H N I C A L S P E C I F I C A T I O N S Audio Output: Frequency: 300-3400 Hz Impedance: Ω Level: 3 dB Output Connector: 3.5 mm stereo jack Audio Input:...

  • Page 189: Audio Interface Option (Digigram)

    C H A P T E R T E C H N I C A L S P E C I F I C A T I O N S Audio Interface Option (Digigram) Power / Environment: Power requirements +5V/+12V/-12V: 0.8A/0.3A/0.2A Operating: temp / humidity (noncondensing): 0°C/+50°C 5%/90%...
  • Page 190 C H A P T E R T E C H N I C A L S P E C I F I C A T I O N S...

  • Page 191: References

    R E F E R E N C E S REFERENCES Literature [BEER92] BEERENDS J. G., STEMERDINK J. A., A perceptual audio quality measure based on a psychoacoustic sound representation, J. Audio Eng. Soc., Vol. 40, No. 12, pp. 963-987, 1992 [BEER94] BEERENDS J.
  • Page 192 R E F E R E N C E S [COLO99] COLOMES C., Schmidmer C., Thiede T., Treuniet W., Perceptual Quality Assessment for Digital Audio: PEAQ – the new ITU Standard for Objective Measurement of Perceived Audio Quality, Proc. Of the AES 17 International Conference, pp.
  • Page 193 R E F E R E N C E S [PRAC98] PRACHT St., Voice Quality, COMMUNICATE, November 1998, p. 43-46 [SEIT89] SEITZER D., BRANDENBURG K., KAPUST R., EBERLEIN E., GERHÄUSER H., KRÄGELOH S., SCHOTT H.: DSP based real time implementation of an advanced analysis tool for audio channels, Proc.
  • Page 194 R E F E R E N C E S Standards [ETSI96] ETSI Technical Report ETR 250, Transmission and Multiplexing (TM); Speech communication quality from mouth to ear for 3,1 kHz handset telephony across networks, ETSI 1996 ISO/IEC/JTC1/SC29/WG11 Draft Document N1557, Evaluation Methods and [ISO97] procedures for MPEG-4 tests, 1997 [ITUR562]...

  • Page 195: Glossary Of Terms

    Glossary of Terms Absolute category rating test method according to the ITU-T recommendation P.800 used for the assessment of speech codecs. Within the ACR test method, a five grade impairment scale is applied. Because of the telecomunication environment the testing is done without a comparison to an undistorted reference.
  • Page 196 Answer Seizure Ratio. Defines the ratio between sucessful call attempts and the total number of calls. The Basic Audio Quality (BAQ) is defined as a global subjective attribute which includes any and all detected differences between the Reference Signal and a processed version of it. Bit Error Rate Call Clarity Index CELP...
  • Page 197 ITU-R The radio communication sector of the International Telecommunication Union, Geneva, (former CCIR), see also http://www.itu.int. ITU-T The telecommunication sector of the International Telecommunication Union, Geneva, (former CCIR), see also http://www.itu.int. LD-CELP Low-Delay CELP (Code Excited Linear Prediction) Speech Coder. According to standard ITU-T G.726. Bit rate of 16 kbit/s.
  • Page 198 The model has been in use since 1987 and has proven its basic reliability. The most important output values of NMR are the masking flag rate, giving the percentage of frames with audible distortions, as well as the total and mean NMR which are different ways of averaging the distance between the error energy and the masked threshold.
  • Page 199 PESQ PESQ stands for “Perceptual Evaluation of Speech Quality” the new ITU standard P.862. At the time PSQM was standardized as P.861, the scope of the standard was to assess speech codecs, used primarily for mobile transmission, like GSM. VoIP was not yet a topic. The requirements for measurement equipment have changed dramatically since then.
  • Page 200 Side Tone Short echoes with a delay shorter than approximately 5ms and an attenuation > 15dB. Subject A test person evaluating the stimuli in a listening test. TAPI Telephony application protocol interface An application protocol interface defined by Microsoft. Type of Service Termination This is the far end of a telephone conversation.

  • Page 201: Index

    Framework 5, 10–11, 29, 40, 54–55, 57, 108–9, 117, 124, 177 Index HOT 142–43, 180 Inp 81, 82, 114, 165, 170–71, 175 InpRefLeft 81, 83, 114, 165, 170, 175 InpRefRight 81, 114, 170 InpTestLeft 81–83, 114, 165, 170, 175 InpTestRight 81, 114, 170 Input 15, 20–21, 30–36, 37, 38, 42, 54–58, 60–...
  • Page 202 Printing 76–77 Properties 59, 92, 95, 108, 119, 124, 128, 135, 150, 157–58, 162, 166, 186 PSQM 9–10, 16–18, 29, 49, 55–57, 81, 83, 85– 86, 117–25, 130–34, 137–38, 143, 157–58, 165–66, 170, 172, 175, 179–80 SDG 14, 103, 113–14 Settings 34, 37, 38, 40–42, 45, 49–51, 54, 58, 59, 62, 72–74, 76, 81, 91–93, 107–9, 111, 113, 115, 124, 125, 133–34, 143, 150, 152, 157, 162,...

  • Page 203: Appendix

    A P P E N D I X APPENDIX White Paper: State of the Art Voice Quality Testing White Paper: OPERA Application Notes (1) ITU-T Recommendation P.861 ITU-T Recommendation P.862 White Paper: PEAQ – The ITU Standard for Objective Measurement of Perceived Audio Quality ITU-R Recommendation BS.1387-1...

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