Technical Committee (TC) Speech and Multimedia Transmission Quality (STQ) Activity Report 2019

Chair: Hans Wilhelm Gierlich, HEAD acoustics GmbH

Responsible for standardization relating to terminals and networks for speech and media quality, end-to-end single media and multimedia transmission performance, Quality of Service (QoS) parameters for networks and services and Quality of Experience (QoE) descriptors and methods.

Our Speech and Multimedia Transmission Quality committee (TC STQ) is responsible for standardization relating to terminals and networks for speech and media quality, end-to-end media transmission performance, Quality of Service (QoS) parameters for networks and services and Quality of Experience (QoE) descriptors and methods.

The objective of TC STQ is to ensure the production and maintenance of end-to-end quality-related deliverables, supporting the timely development of equipment for use with existing and future fixed and mobile network telecommunications service offerings. In addition, these deliverables facilitate the continuous quality assessment of the respective services.

With our Working Group STQ Mobile, the committee works closely with 3GPP and collaborates with other standards organizations.

Principal areas of interest for the committee’s standardization activities include:

  • Terminals and networks for speech and media quality
  • Quality of Virtual Reality (VR) and Augmented Reality (AR) technologies and VR/VR based services
  • End-to-end single media and multimedia transmission performance
  • Voice Control and Internet of Things (IoT) – performance parameters and test methods
  • Quality of Service (QoS) parameters and related measurement methodology for fixed and mobile networks and services, as well as respective Quality of Experience (QoE) descriptors and methods

In addition to ongoing revision of its suite of deliverables, TC STQ published two new Technical Specifications during 2019:

  • TS 103 558 covers methods for objective assessment of listening effort. Based on the results of subjective studies, it considers both normal hearing and hearing-impaired listeners.
  • TS 103 624 describes characterization methodology and requirement specifications for the LC3plus speech codec, developed in cooperation by TC STQ and TC DECT. It also specifies performance requirements for the codec.

Meanwhile our STQ Mobile Working Group published two Technical Reports:

  • TR 103 488 offer service quality evaluation procedures for OTT video streaming. This establishes a framework for applicability/suitability of different video Quality of Service metrics, describing realistic implementation scenarios and ways to compare/assess and combine the performance across different video services. It also addresses the definition of respective QoS parameters and measurement methodology where needed.
  • TR 103 559 presents best practices for robust network QoS benchmark testing and scoring. The tests conducted are telephony, video streaming, data throughput and more interactive applications such as browsing, social media and messaging. This goal is achieved by executing benchmarking tests in designated test areas that represent or actually cover a major part of the users of mobile services. 

STQ and STQ Mobile also adopted further new Work Items during 2019, covering:

  • Subjective test methodologies for the evaluation of echo control systems: this specification will provide test methodologies for subjective assessment of disturbances caused by echo control systems in speech communication devices
  • Objective test method for the evaluation of echo impairments: this work will provide a test method for the prediction of perception of impairments caused by echo control systems
  • Guidelines for assessing statistical properties of benchmarking and scoring results: this report will complement existing work by providing additional methods to establish the statistical properties of benchmarking results, such as convergence of QoS parameters, statistical confidence and dependencies on selection of morphological categories
  • QoS parameters and test scenarios for assessing network capabilities in 5G performance measurements
  • Recommendations on QoS for emerging 5G use cases in relation to network capabilities

MOLE Project STF

The establishment of an ETSI-funded STF (Special Task Force) was approved in January 2019. Under the title ‘Methods for Objective assessment of Listening Effort based on subjective test data bases’ (MOLE Project Step 1), its objective is to offer guidance and methodology regarding intelligibility for hearing impaired users. It is expected that the developed methods can be used for various applications, such as evaluation of terminals and networks, up to hearing aid optimization. This can have a substantial market impact, not only for expert users but for the population at large with impaired hearing capabilities.

Two main tasks of the STF are:

  • creation of a set of test sequences at the acoustic interface
  • designing, conducting and analyzing subjective tests for the acoustic interface

A second STF proposal for MOLE Project Step 2 was approved in September, relating to corresponding tests for the electrical interface.

This activity will result in revision of TS 103 558: ‘Methods for objective assessment of listening effort’ – originally published in November 2019 – with an updated publication expected in Q2 2020.

During the year TC STQ maintained its regular exchange of information with several bodies in order to align the respective standardization work, notably 3GPP SA4 (Codec); ITU-T SG12 (Performance, QoS and QoE; and ITU-T SG16 (Multimedia).

Planning meanwhile progressed for an STQ Workshop, scheduled to be held in October 2020 in Bratislava (Slovakia). The focus of the event will be on Emerging Services for Speech and Audio, covering:

  • Smart Home, Voice Assistant & IoT devices
  • Impact of superwideband and fullband on design, processing, testing and optimization strategies
  • Signal processing between speech communication and voice command mode/speech recognition
  • Parallel task paradigm vs. realistic testing
  • Impact of new services offered in 5G, such as speech recognition and dialogue systems and VR/AR technologies
  • Using mobile devices as a voice assistant device

Media and acoustic aspects of testing from the user’s perspective.

Look out for in 2020 – TC STQ work in progress

  • ETSI Standard (ES) on speech quality performance in the presence of background noise; Part 1: Background noise simulation technique and background noise database
  • Technical Specification (TS) on methods and procedures for evaluating performance of voice-controlled devices and functions: Voice assistant devices
  • TS on transmission requirements for wearable wireless wideband terminals
  • TS on subjective test methodologies for evaluation of echo control systems
  • TS on QoS aspects for popular services in mobile networks; Part 8: Formalized definition of Quality of Service parameters and their computation; Sub-part 2: HTTP-based services
  • Revision to TS on telephony terminals for hearing impaired people
  • Various revisions to ES and TS on transmission requirements for narrowband and wideband VoIP and wireless terminals (handset/headset and hands-free)
  • Revision to TS on sound field reproduction method for terminal testing including a background noise database
  • Revision to TS on methods for reproducing reverberation for communication device measurements
  • Revision to TS on Qualification Methodology and Requirement Specifications for the ETSI LC3plus codec
  • Technical Report (TR) on guidelines for assessing statistical properties of benchmarking and scoring results
  • TR on recommendations on QoS for emerging 5G use cases in relation to network capabilities