Media Over QUIC W. Law Internet-Draft Akamai Intended status: Informational L. Curley Expires: 25 July 2024 Twitch V. Vasiliev Google S. Nandakumar Cisco K. Pugin Meta 22 January 2024 WARP Streaming Format draft-law-moq-warpstreamingformat-01 Abstract This document specifies the WARP Streaming Format, designed to operate on Media Over QUIC Transport. About This Document This note is to be removed before publishing as an RFC. The latest revision of this draft can be found at https://wilaw.github.io/MoQ/draft-law-moq-warpmedia.html. Status information for this document may be found at https://datatracker.ietf.org/doc/draft-law-moq-warpstreamingformat/. Discussion of this document takes place on the Media Over QUIC Working Group mailing list (mailto:moq@ietf.org), which is archived at https://mailarchive.ietf.org/arch/browse/moq/. Subscribe at https://www.ietf.org/mailman/listinfo/moq/. Source for this draft and an issue tracker can be found at https://github.com/wilaw/MoQ. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Law, et al. Expires 25 July 2024 [Page 1] Internet-Draft WARP Streaming Format January 2024 Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on 25 July 2024. Copyright Notice Copyright (c) 2024 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/ license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Conventions and Definitions . . . . . . . . . . . . . . . . . 3 3. Media packaging . . . . . . . . . . . . . . . . . . . . . . . 3 3.1. Packaging mode . . . . . . . . . . . . . . . . . . . . . 3 3.2. Time-alignment . . . . . . . . . . . . . . . . . . . . . 4 3.3. Content protection and encryption . . . . . . . . . . . . 4 4. Catalog . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 5. Media transmission . . . . . . . . . . . . . . . . . . . . . 5 6. Workflow . . . . . . . . . . . . . . . . . . . . . . . . . . 5 7. Security Considerations . . . . . . . . . . . . . . . . . . . 5 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5 9. Normative References . . . . . . . . . . . . . . . . . . . . 5 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 7 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 7 1. Introduction WARP Streaming Format (WARP) is a media format designed to deliver CMAF [CMAF] compliant media content over Media Over QUIC Transport (MOQT) [MoQTransport]. WARP works by fragmenting the bitstream into objects that can be independently transmitted. WARP leverages a simple prioritization strategy of assigning newer content a higher delivery order, allowing intermediaries to drop older data, and video over audio, in the face of congestion. Either complete Groups of Pictures (GOPS) [ISOBMFF] or individual frames are mapped to Law, et al. Expires 25 July 2024 [Page 2] Internet-Draft WARP Streaming Format January 2024 MoQTransport Objects. WARP is targeted at interactive levels of live latency. This document describes version 1 of the streaming format. 2. Conventions and Definitions The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here. This document uses the conventions detailed in Section 1.3 of [RFC9000] when describing the binary encoding. 3. Media packaging WARP delivers CMAF-packaged media bitstreams. This specification references [CMAFpackaging] to define how CMAF packaged bitstreams are mapped to [MoQTransport] groups and objects. Both CMAF Object mappings [CMAFpackaging] Section 4 are supported and a content producer may use either. To identify to consumers which object mapping mode is being used for a given Track, a new track field is defined as per table 1. +===========+================+========+========+======+============+ | Field | Name |Required|Location|JSON | Definition | | | | | |type | | +===========+================+========+========+======+============+ | WARP | warp-packaging |yes |RT |String| See | | packaging | | | | | Section | | mode | | | | | 3.1 | +-----------+----------------+--------+--------+------+------------+ Table 1 3.1. Packaging mode The packaging mode value is defined by Table 2. Law, et al. Expires 25 July 2024 [Page 3] Internet-Draft WARP Streaming Format January 2024 +==================+=================+============================+ | warp-packing | Condition | Explanation | | field value | | | +==================+=================+============================+ | frag-per-group | [CMAFpackaging] | Each CMAF Fragment is | | | 4.1 is active | placed in a single MOQT | | | | Object and there is one | | | | MOQT Object per MOQT Group | +------------------+-----------------+----------------------------+ | chunk-per-object | [CMAFpackaging] | Each CMAF chunk is placed | | | 4.2 is active | in a MOQT Object and there | | | | is one MOQT Group per CMAF | | | | Fragment | +------------------+-----------------+----------------------------+ Table 2 3.2. Time-alignment WARP Tracks MAY be time-aligned. Those that are, are subject to the following requirements: * Time-aligned tracks MUST be advertised in the catalog as belonging to a common render group. * The presentation time of the first media sample contained within the first MOQT Object of each equally numbered MOQT Group MUST be identical. A consequence of this restriction is that a WARP receiver SHOULD be able to cleanly switch between time-aligned media tracks at group boundaries. 3.3. Content protection and encryption The catalog and media object payloads MAY be encrypted. Common Encryption [CENC] with 'cbcs' mode (AES CBC with pattern encryption) is the RECOMMENDED encryption method. ToDo - details of how keys are exchanged and license servers signaled. May be best to extend catalog spec to allow the specification of content protection schema, along with any pssh or protection initialization data. 4. Catalog WARP uses the Common Catalog Format {[COMMON-CATALOG-FORMAT}} to describe the content being produced by a publisher. Law, et al. Expires 25 July 2024 [Page 4] Internet-Draft WARP Streaming Format January 2024 Per Sect 5.1 of [COMMON-CATALOG-FORMAT], WARP registers an entry in the "MoQ Streaming Format Type" table. The type value is 0x001, the name is "WARP Streaming Format" and the RFC is XXX. Every WARP catalog MUST declare a streaming format type (See Sect 3.2.1 of [COMMON-CATALOG-FORMAT]) value of 1. Every WARP catalog MUST declare a streaming format version (See Sect 3.2.1 of [COMMON-CATALOG-FORMAT]) corresponding to the version of this document. The catalog track MUST have a track name of "catalog". A catalog object MAY be independent of other catalog objects or it MAY represent a delta update of a prior catalog object. The first catalog object published within a new group MUST be independent. A catalog object SHOULD only be published only when the availability of tracks changes. Each catalog update MUST be mapped to a discreet moq-transport object. 5. Media transmission The MOQT Groups and MOQT Objects need to be mapped to moq-transport Streams. Irrespective of the Section 3.1 in place, each MOQT Object MUST be mapped to a new moq-transport Stream. 6. Workflow A WARP publisher MUST publish a catalog track object before publishing any media track objects. At the completion of a session, a publisher MUST publish a catalog update that removes all currently active tracks. This action SHOULD be interpreted by receivers to mean that the publish session is complete. 7. Security Considerations ToDo 8. IANA Considerations This document creates a new entry in the "MoQ Streaming Format" Registry (see [MoQTransport] Sect 8). The type value is 0x001, the name is "WARP Streaming Format" and the RFC is XXX. 9. Normative References Law, et al. Expires 25 July 2024 [Page 5] Internet-Draft WARP Streaming Format January 2024 [CENC] "International Organization for Standardization - Information technology - MPEG systems technologies - Part 7: Common encryption in ISO base media file format files", December 2020. [CMAF] "Information technology -- Multimedia application format (MPEG-A) -- Part 19: Common media application format (CMAF) for segmented media", March 2020. [CMAFpackaging] Law, W. and L. Curley, "CMAF Packaging for moq-transport", Work in Progress, Internet-Draft, draft-wilaw-moq- cmafpackaging-00, 2 October 2023, . [COMMON-CATALOG-FORMAT] "Common Catalog Format for moq-transport", September 2023, . [ISOBMFF] "Information technology -- Coding of audio-visual objects -- Part 12: ISO Base Media File Format", December 2015. [MoQTransport] Curley, L., Pugin, K., Nandakumar, S., and V. Vasiliev, "Media over QUIC Transport", Work in Progress, Internet- Draft, draft-lcurley-moq-transport-00, 26 May 2023, . [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . [RFC9000] Iyengar, J., Ed. and M. Thomson, Ed., "QUIC: A UDP-Based Multiplexed and Secure Transport", RFC 9000, DOI 10.17487/RFC9000, May 2021, . Law, et al. Expires 25 July 2024 [Page 6] Internet-Draft WARP Streaming Format January 2024 Acknowledgments * Alan Frindell * Ali Begen * Charles Krasic * Christian Huitema * Cullen Jennings * Hang Shi * James Hurley * Jordi Cenzano * Mike English * the MoQ Workgroup and mailing lists. Authors' Addresses Will Law Akamai Email: wilaw@akamai.com Luke Curley Twitch Email: kixelated@gmail.com Victor Vasiliev Google Email: vasilvv@google.com Suhas Nandakumar Cisco Email: snandaku@cisco.com Kirill Pugin Meta Email: ikir@meta.com Law, et al. Expires 25 July 2024 [Page 7]