T T A S t a n d a r d

T T A S t a n d a r d 제정일 : 2008 년 12 월 19 일 휴대단말에서의 IP 기반멀티미디어스트리밍서비스기술을위한프로파일 Multimedia Streaming Service Technology Based on Internet Protocol for the Portable Devices

제정일 : 2008 년 12 월 19 일 휴대단말에서의 IP 기반멀티미디어스트리밍서비스기술을위한프로파일 Multimedia Streaming Service Technology Based on Internet Protocol for the Portable 본문서에대한저작권은 TTA 에있으며, TTA 와사전협의없이이문서의전체또는일부를상업적목적으로복제또는배포해서는안됩니다. Copyrightc Telecommunications Technology Associations 2008. All Rights Reserved.

서문 1. 표준의목적 본표준은휴대단말에서의 IP 기반멀티미디어스트리밍서비스를제공하는데필요한 기술적인사항과기능요건을제공함을목적으로한다. 2. 주요내용요약 주요내용으로는인터넷프로토콜 (Internet Protocol) 을지원하는휴대단말을위한멀티미디어스트리밍서비스를위한공통적으로요구되는기술요소를네트워크속도및단말의처리능력에따라프로파일형태로제정하되다음과같이계층적으로정의하고있다. 멀티미디어데이터의재생관한형식 - Video Codec - Audio Codec - Still Image Codec 미디어저장파일포맷 - File Format 멀티미디어데이터전송및스트리밍제어 - Media Control Protocol - Media Transport Protocol 실시간자막처리 3. 표준적용산업분야및산업에미치는영향 본표준은다양한형태의휴대단말을위한멀티미디어스트리밍서비스를구축되어나가는데발생할수있는혼란을최소화하고휴대단말멀티미디어스트리밍관련기술의발전과관련응용서비스활성화에기여할것이다. 또한표준화로인하여멀티미디어컨텐츠시장과단말관련반도체및소프트웨어산업을자연스럽게확장시키고활성화시켜나갈것이다. 4. 참조표준 ( 권고 ) i

4.1. 국외표준 ( 권고 ) 아래의참조자료들은본표준에서참조하는조항을포함하거나본표준의조항들을 구성한다. 이표준의발행시점에서아래의버전들이유효하지만, 개정될소지가많으므로 본표준의사용자들을가능한한최신판을찾아보도록권장한다. [1] ITU, ITU-T Recommendation H.264, Advanced Video Coding for generic audiovisual services. [2] IETF, RFC 3550, RTP: A Transport Protocol for Real-Time Applications. [3] IETF, RFC 2326, Real Time Streaming Protocol. [4] IETF, RFC 3551, RTP Profile for Audio and Video Conferences with Minimal Control. [5] IETF, RFC 2327, Session Description Protocol. [6] ISO/IEC, ISO/IEC14496-14:2003, Information technology Coding of Audiovisual objects: MP4 file format. [7] ISO/IEC, ISO/IEC14496-17, Information technology coding of Audio-visual objects: Streaming text format. [8] ISO/IEC, ISO/IEC14496-15, Information technology Coding of Audio-visual objects: AVC file format. [9] IETF, RFC 768, User Datagram Protocol. [10] IETF, RFC 793, Transmission Control Protocol. [11] ISO/IEC, ISO/IEC13818-1, Information technology Generic coding of moving pictures and associated audio information: Systems. [12] IETF, RFC 3984, RTP Payload Format for H.264 Video. [13] IETF, RFC 4396, RTP Payload Format for 3rd Generation Partnership Project (3GPP) Timed Text. [14] IETF, RFC 791, Internet Protocol. [15] IETF, RFC 3640, RTP Payload format for Transport of MPEG-4 Elementary Streams. [16] ISMA, TD00054, ISMA Implementation Specification 2.0. [17] OMTP, OMTP Displays: Definition and Requirements 1.0. [18] OMTP, OMTP Codecs: Definition and Requirements 1.0. [19] ISO/IEC, ISO/IEC14496-3, Information technology coding of Audio-visual objects: Audio ii

[20] ISO/IEC, ISO/IEC14496-12, Information technology coding of Audio-visual objects: ISO Base Media File Format: A file format for storing media format. [21] ISO/IEC, ISO/IEC14496-2, Information technology coding of Audio-visual objects: Visual. [22] ISO/IEC, ISO/IEC11172-3, MPEG-1 Layer III. [23] IETF, RFC 3016, RTP Payload Format for MPEG-4 Audio/Visual Streams [24] 3GPP TS 26.290: "Extended AMR Wideband codec; Transcoding functions". [25] 3GPP TS 26.304: "ANSI-C code for the Floating-point; Extended AMR Wideband codec". [26] 3GPP TS 26.273: "ANSI-C code for the Fixed-point; Extended AMR Wideband codec". [27] 3GPP TS 26.401: "General audio codec audio processing functions; Enhanced aacplus general audio codec; General description". [28] 3GPP TS 26.410: "General audio codec audio processing functions; Enhanced aacplus general audio codec; Floating-point ANSI-C code". [29] 3GPP TS 26.411: "General audio codec audio processing functions; Enhanced aacplus general audio codec; Fixed-point ANSI-C code". [30] IETF RFC 3267: "Real-Time Transport Protocol (RTP) Payload Format and File Storage Format for the Adaptive Multi-Rate (AMR) Adaptive Multi-Rate Wideband (AMR-WB) Audio Codecs", Sjoberg J. et al., June 2002. [31] IETF RFC 4352, RTP Payload Format for the Extended Adaptive Multi-Rate Wideband (AMR-WB+) Audio Codec, J. Sjoberg et al., Jan. 2006. [32] ITU-T Recommendation H.263 (02/98): "Video coding for low bit rate communication". [33] ITU-T Recommendation H.263 Annex X (03/04): "Annex X: Profiles and levels definition". [34] IETF RFC 2429: "RTP Payload Format for the 1998 Version of ITU-T Rec. H.263 Video (H.263+)", Bormann C. et al., October 1998. [35] IETF RFC 3016: "RTP Payload Format for MPEG-4 Audio/Visual Streams", Kikuchi Y. et al.,november 2000. [36] ITU-T Recommendation T.81 (1992) ISO/IEC 10918-1:1993: "Information Technology Digital compression and coding of continuous-tone still images Requirements and guidelines". iii

[37] C-Cube Microsystems: "JPEG File Interchange Format", Version 1.02, September 1, 1992. [38] CompuServe Incorporated: "GIF Graphics Interchange Format: A Standard defining a mechanism for the storage and transmission of raster-based graphics information", Columbus, OH, USA, 1987. [39] CompuServe Incorporated: "Graphics Interchange Format: Version 89a", Columbus, OH, USA, 1990. [40] IETF RFC 2083: "PNG (Portable Networks Graphics) Specification Version 1.0", Boutell T., et al., March 1997. [41] W3C Last Call Working Draft: "Scalable Vector Graphics (SVG) 1.2", http://www.w3.org/tr/2004/wd-svg12-20041027/, October 2004. [42] W3C Last Call Working Draft: "Mobile SVG Profile: SVG Tiny, Version 1.2", http://www.w3.org/tr/2004/wd-svgmobile12-20040813/, August 2004. [43] Standard ECMA-327: "ECMAScript 3rd Edition Compact Profile," June 2001. [44] IETF RFC 1952: "GZIP file format specification version 4.3", Deutsch P., May 1996. [45] 3GPP TS 26.244: "Transparent end-to-end packet switched streaming service (PSS); 3GPP file format (3GP)". 4.2. 국내표준 - TTAS.KO-11.0032/R1, IP STB 기반스트리밍서비스, 2005. - TTAT.3G-26.234 (R6-6.2.0) 5. 참조표준 ( 권고 ) 과의비교 5.1. 참조표준 ( 권고 ) 과의관련성 본표준은목표로하는휴대단말용멀티미디어스트리밍서비스를위한기술적항목들을신규로제정하기보다는기존의참조표준 ( 권고 ) 의내용중휴대단말의성능과무선네트워크에적합한프로파일또는같은목적을가진여러기술중최적인기술을선택하여제정하는방식을취하였다. 따라서어느한표준 ( 권고 ) 을기준으로한것이아니기때문에단순비교보다는항목별로참조한표준 ( 권고 ) 을다음절에서정리하였다. iv

5.2. 참조한표준 ( 권고 ) 과본표준의비교표 참조표준 ( 권고 ) 비고 1. 개요 N.A. 2. 표준의구성및범위 N.A. 3. 정의 N.A. 4. 스트리밍환경 N.A. 4.1 휴대단말 N.A. 4.2 통신프로토콜 Internet Protocol 채택 5. 휴대단말기능 N. A. 5.1 시스템모델 N.A. 5.2 상세기술 N.A. 5.2.1 파일형식 MP4, AVC, 3GPP File format 채택 H.264 Baseline@L1.3, 5.2.2 비디오형식 MPEG-4 SP@L3, H.263 Profile3@L45 부분채택 5.2.3 오디오형식 AAC, HE-AAC, Extended AMR-WB 부분채택 5.2.4 미디어전송프로토콜 RTP, SDP 채택 5.2.5 미디어제어프로토콜 RTSP 채택 5.2.6 RTP 페이로드형식 IETF RFC 3016, 3640 채택 5.2.7 실시간자막 MEPG-4: Part 17 채택 5.2.8 정지영상 JPEG, GIF87a, PNG, SVG Tiny 1.2 부분채택 6. 지식재산권관련사항 본표준의 지식재산권확약서 제출현황은 TTA 웹사이트에서확인할수있다. 본표준을이용하는자는이용함에있어지식재산권이포함되어있을수있으므로, 확인후이용한다. 본표준과관련하여접수된확약서이외에도지식재산권이존재할수있다. 7. 시험인증관련사항 7.1. 시험인증대상여부 - 해당사항없음. v

7.2. 시험표준제정현황 - 해당사항없음. 8. 표준의이력정보 8.1. 표준의이력 판수제정 개정일제정 개정내역 제 1 판 2008.12.19. 제정 8.2. 주요개정사항 - 해당사항없음. vi

Preface 1. Purpose of Standard To facilitate the interoperability of multimedia streaming service for various kinds of mobile devices, this standard provides technical specifications and functional requirements for IP based multimedia streaming service for the devices. 2. Summary of Contents This standard defines functional requirements and technical specifications for multimedia streaming services suitable for network bandwidth and computational capability of mobile devices, based on which some profiles are defined in terms of the following categories: Audio/video codec for decoding audio/visual multimedia contents - Video Codec - Audio Codec - Still Image Codec Media file formats for multimedia contents Media transport and control protocol delivering the contents - Media Control Protocol - Media Transport Protocol Timed text format and transportation 3. Applicable Fields of Industry and its Effect This standard is expected to contribute to reduce the social and technical cost and enlarge the business opportunities in multimedia streaming services as well as its multimedia contents market. Also industries in semiconductor chips and related software confirming to this standard will enjoy the benefits. 4. Reference Standards (Recommendations) 4.1. International Standards (Recommendations) vii

This standard refers to the following references partly or as a whole. As of the time of the publication of this standard the following versions are valid, it is recommend, however, to refer the newest version of them. [1] ITU, ITU-T Recommendation H.264, Advanced Video Coding for generic audiovisual services. [2] IETF, RFC 3550, RTP: A Transport Protocol for Real-Time Applications. [3] IETF, RFC 2326, Real Time Streaming Protocol. [4] IETF, RFC 3551, RTP Profile for Audio and Video Conferences with Minimal Control. [5] IETF, RFC 2327, Session Description Protocol. [6] ISO/IEC, ISO/IEC14496-14:2003, Information technology Coding of Audiovisual objects: MP4 file format. [7] ISO/IEC, ISO/IEC14496-17, Information technology coding of Audio-visual objects: Streaming text format. [8] ISO/IEC, ISO/IEC14496-15, Information technology Coding of Audio-visual objects: AVC file format. [9] IETF, RFC 768, User Datagram Protocol. [10] IETF, RFC 793, Transmission Control Protocol. [11] ISO/IEC, ISO/IEC13818-1, Information technology Generic coding of moving pictures and associated audio information: Systems. [12] IETF, RFC 3984, RTP Payload Format for H.264 Video. [13] IETF, RFC 4396, RTP Payload Format for 3rd Generation Partnership Project (3GPP) Timed Text. [14] IETF, RFC 791, Internet Protocol. [15] IETF, RFC 3640, RTP Payload format for Transport of MPEG-4 Elementary Streams. [16] ISMA, TD00054, ISMA Implementation Specification 2.0. [17] OMTP, OMTP Displays: Definition and Requirements 1.0. [18] OMTP, OMTP Codecs: Definition and Requirements 1.0. [19] ISO/IEC, ISO/IEC14496-3, Information technology coding of Audio-visual objects: Audio [20] ISO/IEC, ISO/IEC14496-12, Information technology coding of Audio-visual objects: ISO Base Media File Format: A file format for storing media format. viii

[21] ISO/IEC, ISO/IEC14496-2, Information technology coding of Audio-visual objects: Visual. [22] ISO/IEC, ISO/IEC11172-3, MPEG-1 Layer III. [23] IETF, RFC 3016, RTP Payload Format for MPEG-4 Audio/Visual Streams [24] 3GPP TS 26.290: "Extended AMR Wideband codec; Transcoding functions". [25] 3GPP TS 26.304: "ANSI-C code for the Floating-point; Extended AMR Wideband codec". [26] 3GPP TS 26.273: "ANSI-C code for the Fixed-point; Extended AMR Wideband codec". [27] 3GPP TS 26.401: "General audio codec audio processing functions; Enhanced aacplus general audio codec; General description". [28] 3GPP TS 26.410: "General audio codec audio processing functions; Enhanced aacplus general audio codec; Floating-point ANSI-C code". [29] 3GPP TS 26.411: "General audio codec audio processing functions; Enhanced aacplus general audio codec; Fixed-point ANSI-C code". [30] IETF RFC 3267: "Real-Time Transport Protocol (RTP) Payload Format and File Storage Format for the Adaptive Multi-Rate (AMR) Adaptive Multi-Rate Wideband (AMR-WB) Audio Codecs", Sjoberg J. et al., June 2002. [31] IETF RFC 4352, RTP Payload Format for the Extended Adaptive Multi-Rate Wideband (AMR-WB+) Audio Codec, J. Sjoberg et al., Jan. 2006. [32] ITU-T Recommendation H.263 (02/98): "Video coding for low bit rate communication". [33] ITU-T Recommendation H.263 Annex X (03/04): "Annex X: Profiles and levels definition". [34] IETF RFC 2429: "RTP Payload Format for the 1998 Version of ITU-T Rec. H.263 Video (H.263+)", Bormann C. et al., October 1998. [35] IETF RFC 3016: "RTP Payload Format for MPEG-4 Audio/Visual Streams", Kikuchi Y. et al.,november 2000. [36] ITU-T Recommendation T.81 (1992) ISO/IEC 10918-1:1993: "Information Technology Digital compression and coding of continuous-tone still images Requirements and guidelines". [37] C-Cube Microsystems: "JPEG File Interchange Format", Version 1.02, September 1, 1992. ix

[38] CompuServe Incorporated: "GIF Graphics Interchange Format: A Standard defining a mechanism for the storage and transmission of raster-based graphics information", Columbus, OH, USA, 1987. [39] CompuServe Incorporated: "Graphics Interchange Format: Version 89a", Columbus, OH, USA, 1990. [40] IETF RFC 2083: "PNG (Portable Networks Graphics) Specification Version 1.0", Boutell T., et al., March 1997. [41] W3C Last Call Working Draft: "Scalable Vector Graphics (SVG) 1.2", http://www.w3.org/tr/2004/wd-svg12-20041027/, October 2004. [42] W3C Last Call Working Draft: "Mobile SVG Profile: SVG Tiny, Version 1.2", http://www.w3.org/tr/2004/wd-svgmobile12-20040813/, August 2004. [43] Standard ECMA-327: "ECMAScript 3rd Edition Compact Profile," June 2001. [44] IETF RFC 1952: "GZIP file format specification version 4.3", Deutsch P., May 1996. [45] 3GPP TS 26.244: "Transparent end-to-end packet switched streaming service (PSS); 3GPP file format (3GP)". 4.2. Domestic Standards - TTAS.KO-11.0032/R1, IP STB streaming service, 2005. - TTAT.3G-26.234 (R6-6.2.0) 5. Relationship to Reference Standards (Recommendations) 5.1. Relationship of Reference Standards (Recommendations) This standard has been developed by referring to various international standards (recommendations) to choose the best-fit proven technology in each technical category according to the mobile devices performance and their network speeds for multimedia streaming services. The international standards referred in each technical category are marked in the main paragraphs although the major relationship is summarized in a table in the next subsection. 5.2. Differences between Reference Standard (Recommendation) and this Standard x

Related International Standards 1. Introduction N.A. created 2. Scope of this standard N.A. created 3. Definitions N.A. created 4. Service Environment N.A. created 4.1 Mobile Devices N.A. created 4.2 Communication Protocol Internet Protocol adopted 5. Functionalities N. A. created 5.1 System model N.A. created 5.2 technologies N.A. created 5.2.1 File Format MP4, AVC, 3GPP File format adopted 5.2.2 Video codecs H.264 Baseline@L1.3, MPEG-4 SP@L3, H.263 Profile3@L45 partially adopted 5.2.3 Audio codecs AAC, HE-AAC, Extended AMR-WB partially adopted 5.2.4 Media transport protocol RTP, SDP adopted 5.2.5 Media control protocol RTSP adopted 5.2.6 RTP Payload formats IETF RFC 3016, 3640 adopted 5.2.7 Timed Text MEPG-4: Part 17 adopted 5.2.8 Still Image JPEG, GIF87a, PNG, SVG Tiny 1.2 partially 6. Statement of Intellectual Property Rights IPRs related to the present document may have been declared to TTA. The information pertaining to these IPRs, if any, is available on the TTA Website. No guarantee can be given as to the existence of other IPRs not referenced on the TTA website. And, please make sure to check before applying the standard. 7. Statement of Testing and Certification 7.1. Object of Testing and Certification - None xi

7.2. Standards of Testing and Certification - None 8. History of Standard 8.1. Change History Edition Issued date Outline The 1st edition 2008.12.19. Established 8.2. Revisions - None xii

목차 1. 개요 1 1.1. 표준의목적 1 1.2. 표준의요구사항 1 2. 표준의구성및범위 1 3. 정의 2 3.1. 용어 2 3.2. 약어 2 4. 휴대단말을위한 IP 기반멀티미디어스트리밍환경 3 4.1. 휴대단말규격 3 4.2. 휴대단말통신규격 4 5. 휴대단말에서의 IP 기반멀티미디어스트리밍서비스를위한기능 4 5.1. 시스템모델 4 5.2. 메커니즘및세부기술요소 5 5.3. 부가기능 9 xiii

Contents 1. Introduction 1 1.1. Goal of this standard 1 1.2. Requirements of this standard 1 2. Constitutions and Scope 1 3. Definitions and Terms 2 3.1. Definitions 2 3.2. Abbreviations 2 4. Environment for IP-based Multimedia Streaming for the Mobile Devices 3 4.1. Requirements of the Mobile Devices 3 4.2. Requirements of Communication Protocol 4 5. Functionalities for Multimedia Streaming Services for the Mobile Devices 4 5.1. System Model 4 5.2 Mechanisms and Detailed Technologies 5 5.3. Auxiliary Functions 9 xiv

휴대단말에서의 IP 기반멀티미디어스트리밍서비스기술을위한프로파일 (Multimedia Streaming Service Technology Based on Internet Protocol for the Portable Devices) 1. 개요 1.1. 표준의목적 본표준은휴대단말에서의 IP 기반멀티미디어스트리밍서비스를제공하는데필요한 기술적인사항과기능요건을제공함을목적으로한다. 1.2. 표준의요구사항 본표준은다음과같은요구사항을고려하여제정되었다. 독점적요소기술이아닌기제정된표준기술을기반 H/W에대한종속성배제 기존모바일서비스업체들의활용기술을충분히고려 현재진행중인휴대네트워크상황에적합한멀티미디어서비스품질을고려 2. 표준의구성및범위 본표준은모바일폰, PDA, 스마트폰등의휴대용단말에공통적으로요구되는인터넷프로토콜 (Internet Protocol) 기반의멀티미디어스트리밍서비스를위한기술요소를네트워크속도및단말의처리능력에따라프로파일형태로제정하되다음과같이계층적으로정의한다. 멀티미디어데이터의재생관한형식 - Video Codec - Audio Codec - 정지영상 (Still images) 미디어저장파일포맷 - File System 1

멀티미디어데이터전송및스트리밍제어 - Media Control Protocol - Media Transport Protocol 실시간자막처리 또한, 휴대용단말을지원하는무선네트워크의특성에따라저대역을고려한미디어스트리밍을고려해야하며, 국제표준인 MPEG 과 H.264 및 ISMA 등의기술요소를수용함으로써호환성을유지하고기존의업계에서확산되어사용중인기술요소를수용하고있다. 본표준의제 4 장과 5 장에서이러한멀티미디어스트리밍서비스를위해필요한 최소한의환경및기능에대해각각기술하고있다. 본표준에서기술하지않은관련 규격은업체의자체규격을따르도록한다. 3. 정의 3.1. 용어 가. 규격준수수준 : 본표준을만족하기위한각항목에대한규격준수요구수준은 REQUIRED, OPTIONAL로구분되어있으며다음과같은의미를가진다. REQUIRED: 규격을만족하기위해서반드시준수해야할항목. OPTIONAL: 업체의결정에따라선택적으로적용할수있는항목. 나. 멀티미디어컨텐츠 : 본규격에서멀티미디어컨텐츠는스트리밍방식으로서비스될수있는비디오, 오디오, 실시간자막으로제한적으로정의한다. 3.2. 약어 본표준에서사용되는약어는다음과같다. 약어 영문 IP Internet Protocol 2

TCP ISMA OMTP AVC RFC RTP RTSP SDP MPEG IETF UDP ITU IEC AAC HE-AAC SBR 3GPP H.264/AVC CIF MP4 QCIF VGA QVGA WiBro AMR-WB Transmission Control Protocol Internet Streaming Media Alliance Open Mobile Terminal Platform Advanced Video Coding Requests for Comments Real time Transport Protocol Real Time Streaming Protocol Session Description Protocol Moving Picture Experts Group Internet Engineering Task Force User Datagram Protocol International Telecommunication Union International Electrotechnical Commission Advanced Audio Coding High Efficiency AAC Spectrum Band Replication 3 rd Generation Partnership Project ITU-T Recommendation H.264 ISO/IEC 14496-10 Advanced Video Coding Common Intermediate Format (352x288) MPEG-4 File Format Quarter CIF (174x144) Video Graphics Array (640x480) Quarter Video Graphics Array (320x240) Wireless Broadband a service name of IEEE802.16e (WIMAX) Adaptive Multi Rate Wide Band 4. 휴대단말을위한 IP 기반멀티미디어스트리밍환경 본절에서는멀티미디어스트리밍환경에대한최소한의규격에대해기술한다. 4.1. 휴대단말규격 IP 기반멀티미디어스트리밍서비스를받을수있는휴대단말은본규격의각프로파일에서요구하는최대스트리밍을실시간으로복호할수있는성능과기능을가져야한다. 또한응용에따라각프로파일에서요구하는데이터를재생할수있는오디오와비디오중적어도하나의장치를장착해야한다. 3

4.2. 휴대단말통신규격 휴대단말과멀티미디어서버와의통신은 IP 망을지원해야한다. 본규격에서는 IP 이하하위수준의통신방식은휴대형이므로주로무선통신을제공해야하며때로는유선이될수도있으므로유무선모두가능하며본표준에서 IP 프로토콜아래의스택에대해서는특별히제한하지않으나단말이만족하고자하는프로파일에서규정한대역폭이상을가져야한다. REQUIRED: Internet Protocol IETF RFC 791 [14] 5. 휴대단말에서의 IP 기반멀티미디어스트리밍서비스를위한기능 5.1. 시스템모델 멀티미디어스트리밍서비스시스템구조는그림 1 과같이스트리밍서버, 저장장치, 휴대단말, IP 네트워크, 휴대단말과 IP 네트워크를접속하는무선 / 유선네트워크로이루어진다. 멀티미디어는본규격에서는동영상과텍스트를위주로한다. 서버에서는멀티미디어스트리밍을위한동영상의부호화, 저장, 스트림전송등의기능을가져야하고, 서버와휴대단말간은 Wireless LAN, Wibro, WCDMA (Wideband Code Division Multiple Access), CDMA2000, LAN 등이동을허용하는다양한형태의하위수준의무유선프로토콜을사용하되반드시 IP 프로토콜스택을상위수준에지원하여야한다. 휴대단말이제공하는전송대역폭은각동시서비스되는각미디어들의최대비트율의합보다커야한다. 무선접속네트워크 (Cellular, WLAN, Wibro 등 ) 멀티미디어컨텐츠 미디어스트리밍서버저장소 IP 네트워크 ( 인터넷 ) 휴대단말 (IP 지원 ) ( 그림 5-1) 시스템모델 본표준은제공하는서비스및단말의특성에따라여러개의프로파일로나눈다. 프로파일 0 는기존에많이존재하고있는 MPEG-4 미디어및저대역폭을갖는 휴대전화단말의호환성을위해제공된다. 프로파일 1 은대역폭 1M 이상을가지는 PDA, 4

DMB 등의휴대단말에압축률과품질이좋은 H.264/MPEG-4 Part 10: AVC 로새로제작되는컨텐츠를제공하기위한것이다. 향후전송대역폭이크고성능이좋은단말이계속해서출시될것으로예상되며프로파일번호가올라갈수록고품질의멀티미디어스트리밍서비스를확장하도록한다. 본규격은공통기술규격과프로파일별로독립적인각세부기술요소를규정하며, 현재까지정의된각프로파일의독립적인주요특징을요약하면다음과같다. 프로파일 0: MPEG-4 Visual, Simple Profile@L3, AAC, 512kbps 이하대역폭 H.263 Video, Profile3@L45, Extended AMR-WB, 512kbps 이하대역폭프로파일 1: AVC Baseline@L1.3, AAC (HE-AAC 수용 ), 1Mbps 내외의대역폭 5.2. 메커니즘및세부기술요소 5.2.1. 파일형식 ( 포맷 ) 미디어에대한저장파일포맷은코덱에의존하지않는 ISO 베이스미디어 파일포맷 (ISO/IEC 14496-12:ISO Base Media File format) 에기반하여코덱에의존적인 부분을추가한다음의확장규격을사용한다. REQUIRED: ISO Base Media File Format ISO/IEC 14496-12 [20] 프로파일 0: REQUIRED: MP4 파일포맷 ISO/IEC 14496-14 [6], 3GPP 파일포맷 [45] OPTIONAL: AVI (Audio Video Interleave) 파일포맷 프로파일 1: REQUIRED: AVC 파일포맷 ISO/IEC 14496-15 [8], 3GPP 파일포맷 [45] 5.2.2. 비디오형식 기존의콘텐츠및휴대단말의호환성을위해서프로파일 0 에서는 MPEG 4 코덱 (MPEG-4: Part 2) 를사용하며프로파일 1 에서는높은압축률및품질을위해서 MPEG 4 AVC 코덱을사용한다. 5

프로파일 0: REQUIRED: MPEG-4: Visual-ISO/IEC 14496-2 [21], Simple Profile@L3, 최대 CIF 또는 QVGA 해상도, 최대 384kbps, 최대 30fps H.263 Video - ITU-T Recommendation H.263 [32][33], Profile 3 Level 45, 최대 CIF 또는 QVGA 해상도, 최대 384kbps, 최대 30fps OPTIONAL: MPEG-4: Visual-ISO/IEC 14496-2 [21], Simple Profile@L1, 최대 QCIF 해상도, 최대 64kbps, 최대 15fps 프로파일 1: REQUIRED: H.264: Advanced Video Coding [1], Baseline@Level 1.3, 최대 CIF 또는 QVGA 해상도, 최대 768kbps, 30fps OPTIONAL: H.264: Advanced Video Coding [1], Baseline@Level 1, 최대 QCIF 해상도, 최대 64kbps, 최대 15fps 5.2.3. 오디오형식 오디오는기본으로 AAC 및 Extended AMR-WB 코덱을지원한다. 프로파일 0 / 프로파일 1: REQUIRED: Extended AAC Plus (Advanced Audio Coding-LC), 3GPP TS 26.401 [27][28][29],ISO/IEC 14496-3 [19], AAC, 최대 2 개채널지원, 최대 48kHz 샘플링 Extended AMR-WB, 3GPP TS 26.290 [24][25][26], AMR-WB, 최대 2 개채널지원, 최대 48kHz 샘플링 OPTIONAL: HE-AAC (High Efficiency Advanced Audio Coding) ISO/IEC 14496-3 [19] HE-AAC@L2, 최대 2 개채널지원, 최대 48kHz 샘플링 OPTIONAL: MP3 ISO/IEC 11172-3: MPEG-1 Layer III, [22] 128kbps 비트율, 최대 48kHz 샘플링 5.2.4. 미디어전송프로토콜 6

오디오비디오데이터를휴대단말이서버에서 IP 를통해전송받는것은프로파일에 관계없이 RTP (Real-time Transport Protocol) 를사용한다. REQUIRED: RTP: A Transport Protocol for Real-time Applications IETF RFC 3550 [2] REQUIRED: RTP Profile for Audio and Video Conferences with Minimal Control IETF RFC 3551 [4] 데이터전송프로토콜로는 UDP, TCP 를사용해야하며, 유니캐스트또는멀티캐스트 방식을사용할수있다. REQUIRED: UDP (User Datagram Protocol) IETF RFC 768 [9] REQUIRED: TCP (Transmission Control Protocol) IETF RFC 793[10] 5.2.5. 미디어제어프로토콜 서버와수신단말간의통신제어를위해서는프로파일에관계없이 RTSP(Real Time Streaming Protocol) 을사용한다. RTSP 는신뢰성을위해서 RTP 와다른포트를 사용하며선택적으로 TCP 를사용한다. RTSP 의송수신정보는 SDP 프로토콜을 사용한다. REQUIRED: RTSP (Real Time Streaming Protocol) IETF RFC 2326 [3] REQUIRED: SDP (Session Description Protocol) IETF RFC 2327 [5] 5.2.6. RTP Payload 포맷 미디어데이터에대한페이로드포맷은데이터의포맷에따라다음규격을따른다. MPEG-4 Video: 7

REQUIRED: RTP payload Format for MPEG-4 Video IETF RFC 3016 [23] H.263 Video: REQUIRED: RTP payload Format for H.263 Video IETF RFC 2429 [34] MPEG-4 AVC Video: REQUIRED: RTP payload Format for H.264 Video IETF RFC 3984 [12] Audio: REQUIRED: RTP Payload Format for MPEG-4 Streams IETF RFC 3640 [15] REQUIRED: RTP Payload Format for Enhanced aacplus and MPEG-4 AAC, IETF RFC 3016 [35] REQUIRED: RTP Payload Format for Extended AMR-WB, IETF RFC 3267, 4352 [30][31] 5.2.7. 실시간자막 (Timed text) 실시간자막 (Timed text) 포맷은 MPEG-4: Part 17 을따른다. OPTIONAL: Streaming text format ISO/IEC14496-17 [7] Timed Text 를위한페이로드는 IETF 표준을따른다. OPTIONAL: RTP Payload Format for 3GPP Timed Text IETF RFC 4396 [13] 5.2.8. 정지영상 (Still images) 정지영상에대한재생기능을지원시는다음의규격을준수한다. 8

REQUIRED: ISO/IEC JPEG [36], JFIF 복호기 [37] 5.2.8.1. 비트맵그래픽스 (Bitmap graphics) 비트맵그래픽스기능을지원시는다음의기술규격을따른다. REQUIRED: GIF87a [38], GIF89a [39], PNG [40] 5.2.8.2. 벡터그래픽스 (Vector graphics) 벡터그래픽스기능을지원시는다음의기술규격을준용한다. REQUIRED: SVG Tiny 1.2 [41][42], ECMAScript [43] SVG 콘텐츠에대한압축포맷은 GZIP [44] 을사용한다. 5.3 부가기능 본표준안에부가하여서비스의품질과성능을높이기위하여필요할경우새로운 기능을추가할수있다. 이러한추가기능은다음버전의표준안에서정의한다. 9

표준작성공헌자 표준번호 : 이표준의제정 개정및발간을위해아래와같이여러분들이공헌하였습니다. 구분성명위원회및직위 연락처 (E-mail 등 ) 소속사 표준 ( 과제 ) 제안 김재명 임베디드 SW 프로젝트그룹의장 042-860-5042 jaemkim@etri.re.kr ETRI 표준초안제출 김병규 임베디드 SW 프로젝트 그룹위원 042-860-5766 bg.kim@ieee.org ETRI 김재명 임베디드 SW 프로젝트그룹의장 042-860-5042 jaemkim@etri.re.kr ETRI 표준초안검토 정영준 임베디드 SW 프로젝트그룹간사 042-860-6397 jjing@etri.re.kr ETRI 및작성 이은서 임베디드 SW 프로젝트그룹위원 054-820-6306 eslee@andong.ac.kr 안동대학교 외임베디드 SW 프로젝트그룹위원 표준안심의 박승민 기반소프트웨어기술위원회의장 042-860-5576 minpark@etri.re.kr ETRI 외기술위원회위원 사무국담당 박정식 - 오세순 - 031-724-0080 jspark@tta.or.kr 070-7780-0085 ssoh@tta.or.kr TTA TTA 10

휴대단말에서의 IP 기반멀티미디어스트리밍서비스기술을위한프로파일 (Multimedia Streaming Service Technology Based on Internet Protocol for the Portable Devices) 발행인 : 한국정보통신기술협회회장발행처 : 한국정보통신기술협회 463-824, 경기도성남시분당구분당로 47 Tel : 031-724-0114, Fax : 031-724-0109 발행일 : 2008.12.