1 MMS Default CODEC Assessment 3GPP2 TSG-C WG1 Source: Motorola Alberto Gutierrez Senaka Balasuriya Soumitra Das Randall Grund Recommendation: Review and discuss in consideration of MMS codec selection. Motorola Inc. grants a free, irrevocable license to 3GPP2 and its Organizational Partners to incorporate text or other copyrightable material contained in the contribution and any modifications thereof in the creation of 3GPP2 publications; to copyright and sell in Organizational Partner's name any Organizational Partner's standards publication even though it may include all or portions of this contribution; and at the Organizational Partner's sole discretion to permit others to reproduce in whole or in part such contribution or the resulting Organizational Partner's standards publication. Motorola Inc. is also willing to grant licenses under such contributor copyrights to third parties on reasonable, non-discriminatory terms and conditions for purpose of practicing an Organizational Partner’s standard which incorporates this contribution. This document has been prepared by Motorola Inc. to assist the development of specifications by 3GPP2. It is proposed to the Committee as a basis for discussion and is not to be construed as a binding proposal on Motorola Inc.. Motorola Inc. specifically reserves the right to amend or modify the material contained herein and to any intellectual property of Motorola Inc. other than provided in the copyright statement above. C

2 References CDG, Correspondence to TSG-C WG1 Chair regarding MMS default CODEC selection Criteria, C Nokia, 3GPP2 MMS Speech Codec Selection Criteria Analysis, C Qualcomm, Considerations for Choosing Vocoders in 3GPP2 MMS, C B

3 MMS Default CODEC Criteria Interoperability –Ensure compatibility for intra-CDMA2000 carrier MMS inter-working –Ensure compatibility for MMS roaming between two CDMA2000 Networks –Minimize complexity of transcoding when inter-working with 3GPP MMS systems –Support minimum complexity of transcoding option when inter-working with non- wireless systems Wide-spread use in wireless systems –Broad commercial availability in terminal devices –Supported in most network infrastructure –Minimize complexity of CDMA2000 terminal devices Wide-spread use in non-wireless systems: –Supported in computer industry (laptops, desktops, operating systems, etc.) –Supported by applications and content developers Performance –Bit-rate (fixed or variable) –Required processing overhead –SAR, perceived audio quality

4 MMS Default CODEC Criteria Comments Interoperability (No Trans-coding Support) –Intra CDMA2000 Carrier: EVRC, QCELP-13, AMR –Inter CDMA2000 Carrier: EVRC, QCELP-13, AMR –3GPP and 3GPP2: AMR –With Non-Wireless Systems: AMR Deployment Criteria –Broad Commercial Availability in Terminal Devices: AMR (GSM/UMTS), EVRC (CDMA/IS-95), QCELP-13 (CDMA/IS-95) –Support in Most Network Infrastructure: EVRC (CDMA Networks), QCELP- 13 (CDMA Networks), AMR (GSM Networks) –Minimize Complexity of CDMA2000 Terminal Devices: EVRC, QCELP-13 –Broad Support in Computer Industry: AMR –Broad Support by Applications and Content Developers: AMR Performance Criteria (from Nokia Table) –Bit Rates (Kbps): EVRC (8.55, 4, 8); QCELP-13 (13.3, 6.2, 1); AMR (12.2, 10.2, 7.4, 6.7, 5.9, 5.15, 4.75) –Processing Overhead (WMOPS): EVRC (20), QCELP-13 (17.8), AMR (16.8) –Memory (Kbytes): EVRC (42), QCELP-13 (27.7), AMR (38.8) –SAR, Perceived Audio Quality: EVRC (3.852), QCELP-13 (3.832), AMR (3.932) Interoperability (Minimum Complexity with No Trans-coding Support) –AMR provides best Interoperability –AMR addresses higher percentage of computer market via Windows XP vs smaller portion addressed by QCELP- 13 via Eudora/Quicktime Deployment Criteria –Across all systems the choice of AMR provides broadest deployment –Within CDMA systems (i.e., excluding GSM/UMTS), EVRC & QCELP-13 deployment comparable Performance Criteria –Differentiating point from the MMS perspective is file size where EVRC provides lowest file size at a given quality level. AMR and QCELP result in approximately 1.5 times the file size.

5 Motorola view on the utility of a mandatory CODEC. There are some advantages to a mandatory CODEC –Proper selection of a mandatory codec would eliminate trans-coding for inter and intra GSM/UMTS, CDMA/IS-95, and Windows systems messaging –Even when interworking with GSM/UMTS and wireline/internet services is not a concern, selection of a mandatory codec eliminates the need for trans-coding for intra and inter 3GPP2 system messaging

6 Motorola view on QCELP-13 vs. EVRC EVRC was developed to provide better performance (compression efficiency, i.e., lower bit rates and smaller file sizes) at equivalent or better listening quality QCELP-13 file sizes will be ~1.5 x EVRC file sizes

7 Compatibility with Non-Wireless Systems QCELP-13 –Eudora and Quicktime support QCELP-13. Mac OS supports Quicktime –IETF RFC defines QCELP-13 RTP payload formats - describes how compressed PureVoice audio as produced by the Qualcomm PureVoice CODEC [1] may be formatted for use as an RTP payload type ( EVRC –PacketVideo’s pvPlayer supports EVRC –IETF work on EVRC is in progress. The draft describes the RTP payload format for Enhanced Variable Rate Codec (EVRC) Speech and Selectable Mode Vocoder (SMV) Speech ( – status is in RFC editor queue - close to RFC statushttp:// AMR –Windows XP supports AMR –IETF RFC defines specifies a real-time transport protocol (RTP) payload format to be used for Adaptive Multi-Rate (AMR) and Adaptive Multi- Rate Wideband (AMR-WB) encoded speech signals ( AMR is used by the computer industry and will likely continue to gain greater acceptance/use. Limited use for EVRC and QCELP-13

8 Conclusions Default CODEC is beneficial for interoperability between 3GPP2, 3GPP, and Non-Wireless systems. The best choice for overall interoperability is AMR For interoperability limited to CDMA systems, if the industry finds that a native CDMA MMS default CODEC is preferred, then EVRC is the best choice due to overall better performance.