Workshop on Wideband Speech Quality in Terminals and
– Workshop on Wideband Speech Quality in Terminals and Networks supported by:
• Wideband – a business case? – Where is wideband technology to be used? – What type of terminals/interfaces do we have to expect? – What are the implications on design, testing and optimization?
• The general requirements for wideband speech transmission – Are there new quality parameter to be taken into account? – What speech quality parameters from narrow band systems can be used, how do they need to be adapted? – To what extent are requirements and limits different?
• Requirements for wideband speech (communicational) quality and wideband audio – What are the differences between these applications and how do these nee to be reflected in the requirements? – How can existing specifications be aligned? – Is there a need of new specifications in order to address the mixed use of wideband audio and wideband speech communication?
• The acoustical interface: – What is the right reference point (DRP-ERP -freefield)? – How should we measure (Setup, testing techniques)? – What environmental conditions do we have to choose?
• Signal processing in wideband terminals – What are the implications of the use of wideband codecs? – Are there generally different signal processing techniques? – How do existing signal processing techniques need to be adapted?
• Networks for wideband systems – Are there specific requirements for networks used for wideband speech communication? – How can existing standards be adapted to wideband speech communication? – What are the requirements on networks for mixed applications (speech/audio/video)?
• Planning for wideband speech services – Are new parameters in our planning tools needed? – Can the e-model be adapted to wideband – what changes are needed? – What Qo. S parameters are needed – in addition to the ones used in narrow band systems?
Workshop results:
Subjective Testing • Conversational tests for usability of WBsystems with background noise (sound quality, intelligibility, overall quality) • Intelligibility tests (NB<->WB) • Echo and background noise tests
Terminals and acoustical interfaces • Radiation directivity of HATS • Desired frequency responses in sending and receiving (unifying existing standards I-ETS 300 245 -5/6, TIA 920, ITU. . . ) • Test methods for terminals using complex signal processing esp. HFT • Test methods for wideband sound quality: extention of PESQ or alternative methods
Speech Quality Parameters Narrow band Wide band (Speech) sound quality Different quality perception Loudness (WB) Quality of background noise transmission Different quality Perception ? Delay and echo Double talk capability Switching and echo single talk/double talk Different quality Perception ? Different quality Perception (System) noise
Modelling • Required: “intermediate e-model” for wideband • Estimating the necessary R-scale extension based subjective test results (R ~ 111 -142) • New impairment factors for wideband codecs • Discussion of the additivity assumption
- Slides: 13