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Enhanced Voice Services – EVS IWAENC 2014 Presentation

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Enhanced Voice Services – EVS IWAENC 2014 Presentation September 2014 Enhanced Voice Services – EVS IWAENC 2014 Presentation Confidential and Proprietary - Qualcomm Technologies, Incorporated. All Rights Reserved. Topics of this Presentation Benefits of EVS Standardization framework Specifications Algorithmic overview and special aspects Delay and complexity Embedding EVS in 3GPP system Quality characterization Deployment / commercialization aspects 2 EVS – Next Gen 3GPP Speech Coding for Improved User Experience in Telephony AMR 4.75 kbps 12.2 AMR-WB 6.6 kbps 23.85 EVS 5.9 kbps 128 EVS Quality AMR- WB AMR 1995 2002 2014 3 3GPP Voice Service Evolution AMR AMR-WB EVS Standards 2000 2002 2014 Commercial 2001 2010 2015 WCDMA+ 4 Different Voice Solutions Carrier Grade Voice Best Effort Voice CS Voice IMS/RCS VoIP OTT-VOIP OPERATOR OPERATOR 3RD PARTY PORTAL PROVIDED PROVIDED PROVIDED PROVIDED SERVICE SERVICE SERVICE SERVICE TAPI Operator 3rd party HLOS Dialer Client Client Client CDMA UMTS VoMBB VoLTE VoWiFi VoWAN Very reliable, fully interoperable, but Ensures Consistent & Seamless Interoperable but Limited to Lacks IP Mobility, Connectivity & Interop lacks personalization Rich Voice Experience VoLTE Coverage with other mVoIP EVRC Family AMR Family Customized Family EVS Family Internet Family G.7xx Family 5 What is EVS? 3GPP Speech Conversation / Telephony Coder EVS – Enhanced Voice Services − Next generation 3GPP speech coding − Following the successful FR, HR, EFR, AMR, AMR-WB codecs − Designed for packet-switched networks / mobile VoIP − VoLTE is a key target application − Application in other networks − AMR-WB interoperable mode − Rel-12 Work Item in 3GPP preceded by a Study Item TR 22.813 Key features − Super-wideband speech (32 kHz sampling) – improved speech quality − Source-controlled variable bit-rate operation – improved capacity − Designed for VoIP – improved robustness − Improved music performance − Wide bit-rate range and all bandwidths for maximum flexibility − Backward interoperable mode to AMR-WB Standardization process − Qualification phase − Selection phase − Characterization phase 6 3GPP EVS is the Next Generation Speech Coder Speech quality determines user experience − Ensuring voice quality on new VoLTE deployments − EVS addresses all networks – mobile VoIP with QoS, best effort VoIP, CS 3GPP goals of Enhanced Voice Services (EVS) standardization − Feature-rich coder − Designed for VoIP applications such as MTSI in TS 26.114 − It is further desirable that the benefits of EVS are available for users of other networks such as CS − NB, WB, SWB bandwidths, FB optional, high robustness mode − Bit rates: 7.2, 8, 9.6, 13.2, 16.4, and 24.4 kb/s gross rates that comply with LTE TBSs; 32, 48, 64, 96, 128 kb/s − Quality improvements – improving user experience − Better quality in VoLTE and UMTS (with no new RAB) − Evolution path: EVS provides SWB at around 13 kbps – lower rate and lower delay SWB than other industry coders without sacrificing quality − Better quality for music and mixed content in conversational applications − Capacity improvements – increasing system efficiency − VBR at 5.9 kbps provides high capacity mode − Robustness improvements – optimized behavior in VoIP applications − More robust NB/WB through significantly better error resilience − High robustness mode 7 EVS- Enhanced Voice Services The Ultimate Codec of Choice for Mobile Telephony EVS More natural sounding speech SWB and improved music quality @13.2 kbps Better Voice Quality BetterVoice AMR-WB WB Improves voice clarity and intelligibility @12.65 kbps AMR NB Toll quality narrowband voice @ 12.2 kbps EVS @13.2kbps provides Super Wideband Voice Quality at comparable bit-rate to AMR & AMR-WB 8 EVS Benefits Better Capacity Enhanced Error Resiliency Super Wideband: 13.2 – 128 kbps Optimized for VoLTE and Circuit Switched Networks Wideband: 5.9 – 128 kbps Improved Robustness to packet Narrowband: 5.9 – 13.2 kbps loss compared to AMR-WB Support of Source-Controlled Variable Bit Rate operation Extended audio bandwidth: 50 Hz to 16 kHz Better quality NB and WB Voice compared to AMR & AMR-WB Superior Quality Entertainment quality music coding Super Wideband (Voice and Music) Wideband (Voice) Narrowband (Voice) ~7kHz 16kHz Low frequencies increases naturalness, presence High frequencies improves voice clarity and Reproduces better and comfort intelligibility audio and music 9 Enhanced Error Resiliency Superior Voice Quality Error Resilience Improvement for 3GPP Speech coding performance delay loss profile (6% FER) (with background car noise) 3.5 4 3 EVS Performance 3 2.5 2 2 23.85 13.2 3.5 Music coding performance (3% FER) 12.65 23.85 13.2 12 16 AMR-WB EVS AMR-WB EVS Opus 3 2.5 2 19.85 23.85 13.2 AMR-WB EVS Enhanced In-Call Music Quality 10 EVS – Solution for Each Situation Jitter Buffer Management NB WB SWB FB Stereo New EVS New EVS AMR-WB New EVS New EVS Modes (CBR) New EVS Modes New EVS Modes New EVS Modes Modes Modes Interop Modes 7.2-128 kb/s 7.2-128 kb/s (optional) (optional) (CBR) (VBR) Modes (VBR) Speech Speech Speech Speech Music Speech Speech Music Speech Music Speech Music 7.2-13.2 kb/s 5.9kb/s 6.6-23.85 7.2-128 kb/s 7.2-128 5.9 kb/s 13.2-128 13.2-128 7.2-128 kb/s 7.2-128 kb/s 7.2-128 kb/s 7.2-128 kb/s (avg) kb/s kb/s (avg) kb/s kb/s Better Capacity Better Music Better Quality Improved Error Resilience Same NB/WB quality as legacy Near AAC Quality at much Same capacity as legacy Much better than AMR-WB, VoIP EVS? lower delay NB/WB Optimizations Why Deploy 11 3GPP EVS Standardization Process in Rel-12 Requirements phase – design constraints and performance requirements Candidate coders − 13 companies submitted a candidate by 16 November 2012 − Ericsson, Fraunhofer, Huawei, Motorola, Nokia, NTT, NTTDoCoMo, Orange, Panasonic, Qualcomm, Samsung, VoiceAge, ZTE − Standardization by competition Qualification phase − Aim is to keep the most promising 5 candidates for selection − Extensive testing − 12 experiments, each candidate is tested in-house and in another listening lab − Global Analysis Lab performs collection and analysis of test results − Qualification meeting in March 2013 agreed in 5 candidates All proponents announced a collaborative development of a joint candidate Selection phase – single joint candidate − Codec selection is based on extensive testing in neutral listening labs − Selection meeting in August 2014 agreed to adopt the joint candidate as EVS standard − Agreement on most EVS specifications Characterization phase − Aim is to test the coder performance for all conditions and special signals / conditions Approval of remaining EVS Specifications and Technical Report 12 EVS Rel-12 Standardization Timeline 3GPP SA4#80 Aug 4 3GPP SA4#80bis: codec selection and approval of specifications Submission of EVS Aug 30 Approval of EVS executable 3GPP SA4#81 Technical Report and for testing SA approval of floating-point spec EVS standard Nov 6 June 27 Dec 10 Sep 15 2014 2015 Jun Jul Aug Sep Oct Nov Dec Selection Testing Characterization Testing EVS Prototypes Available for Preliminary Lab/Field Testing EVS Engineering Build Available For IOT and Field Trials 2015 EVS over 3G UTRAN CS Work Item (Rel-13) 13 EVS Is A Global Collaboration Broad Industry Support Across the Ecosystem Keys For Successful Deployment Qualcomm • Codec hw/sw support (i.e., chipset, IMS/RCS client, Fraunhofer Samsung voice pre/post-proc, etc.) VoiceAge Nokia • Super Wideband terminal acoustic designs Ericsson EVS Panasonic • Infra support (IMS, gateways, etc) 12 Party Collaboration • Test Equipment Support (call box, IMS, SWB Huawei NTT acoustics, voice quality) ZTE NTT DoCoMo Orange • EVS support in voice services outside of mobile ecosystem (e.g., wireline VoIP, Enterprise VoIP & Video Telephony, etc.) 14 EVS Design Requirements Superwideband (0- 16 kHz) Coding of Speech better than AMR-WB Constraints on Frame Length, Improved Error Max. Resilience Improved Algorithmic for both Circuit Wideband Source Coding of Delay, Switched and (0-8 kHz) Coding of Controlled Music Complexity, Packet Switched Speech better than Variable Rate for In-call Music JBM, Rate Communication AMR-WB; inclusion of Coding (Music on hold Switching, and AMR-WB IO and Ringback) PLC, RTP VoIP Capability Payload Format, VAD/DTX/CNG Narrowband (0-4 KHz) Coding of Speech better than AMR 15 EVS Requirements in SWB at Low Rates Category Bitrate (kbit/s) FER DTX Requirements Clean speech 13.2 0% On†/Off NWT G.722.1C @ 32 -26,-16,-36dBov 16.4 NWT G.722.1C @ 48 24.4 NWT G.718B @ 36 Clean speech 13.2 x=3%, Off NWT G.722.1C @ 48, x% FER -26 dBov 16.4 6% On† for 13.2 NWT G.719 @ 48, x% FER 24.4 NWT G.719 @ 56, x% FER Noisy Speech (Car, Office, 13.2 0% On‡/Off NWT G.722.1C @ 24 when EVS DTX off Street) NWT AMR-WB @19.85 DTX on when EVS DTX on -26 dBov 16.4 NWT G.722.1C @ 32 when EVS DTX off NWT AMR-WB @23.05 DTX on when EVS DTX on 24.4 NWT G.722.1C @ 48 when EVS DTX off NWT AMR-WB @23.85 DTX on when EVS DTX on Noisy Speech (Car, Office, 13.2 x=3%, Off NWT G.722.1C @ 24, x% FER and DTX off Street) 6% On‡ for 13.2 NWT AMR-WB @19.85, x% FER and DTX on when EVS DTX on -26 dBov 16.4 NWT G.722.1C @ 32, x% FER 24.4 NWT G.722.1C @ 48, x% FER 16 3GPP EVS Specifications Spec No. Title Status: agreed TS 26.441 EVS Codec General Overview For approval TS 26.442 EVS Codec ANSI C code (fixed-point) For approval TS 26.443 EVS Codec ANSI C code (floating point) Draft TS 26.444 EVS Codec Test Sequences For approval TS 26.445 EVS Codec Detailed Algorithmic Description For approval TS 26.446 EVS Codec AMR-WB Backward Compatible Functions For approval TS 26.447 EVS Codec Error Concealment
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