This specification defines the Mezzanine stream format for the contribution delivery of HD and UHD content.
Within a distribution system a single broadcast contribution feed can be used to support multiple broadcast feeds. For example a single feed could support a simulcast IPTV service, DTT Service and a DTH service.
Case A in Figure 1 is based on HD-SDI (SMPTE 292M)
CompressedIP contribution is defined in Cases B and C defined here for HD and UHD contribution
Original Document : Simulcast Delivery Over IP v1 ![https://docs.google.com/presentation/d/1wxBFwKbxcUJg-gIKDacQQ9rA-JISyvyYd0lfxgaci3Q/edit#slide=id.ge8cd77181_0_127
The channels will originate at hosting sites in a pair of redundant racks on ‘red and blue’ paths. The streams are encoded to a mezzanine HD transport stream format at 25Mbps. This will ensure sufficient quality for the subsequent transcoding.
The HD streams will be transported as multicast and distributed over a private network to the data centres acting as points of presence. The network is self-healing and will re-route streams in the event of circuit or equipment failure.
The streams will be presented on nominated IP addresses and ports. The client will be required to provision connectivity to access the streams.
Resolution: 1920 x 1080 Codec: H.264 Profile/Level: HP@4.0 Bitrate: 25 Mbps CBR Frame Rate: 25 GOP: 50 frames Colour: 4:2:0
Codec: AAC-LC Bitrate: 256 Kbps
MPEG 2 TS over Multicast UDP/RTP
DRAFT
Author: Keith Millar
Date: 24/10/2018
Version: 0.1
Formating update: Clive Santamaria
Date: 23/11/2018
Version: 0.2
Converted from original internal document https://docs.google.com/document/d/1IRstCMCU3iLHEv_rMMy__LTXxAiHVwKPcE1GUjurrYM/edit#
This document defines the Mezzanine stream format for the contribution delivery of UHD content.
Within a distribution system a single broadcast contribution feed can be used to support multiple broadcast feeds. For example a single feed could support a simulcast IPTV service, DTT Service and a DTH service, where each broadcast service requires a different set of markers.
The UHD content shall be as follows:
Signalled as HLG10
3840 x 2160
10 bit
4:2:2
Intra frame
50 Hz, Progressive
BT.2020 non-constant luminance
BT.2100
Narrow range only
The AV data shall be encapsulated as an MPEG2 Single Program Transport Stream with a maximum bitrate of 100Mbits/s.
The Video frames shall be encapsulated using PES per Frame, with the start of a video frame starting in a new PES packet.
The MPEG2-TS shall signal the Video component within the PMT by setting the “stream type” to 0x027 and including a “HEVC_video_decsriptor” (See ETSI TS 101 154 v.2.3.1, clause 4.1.8.19a) with the component declaration.
The Video shall be encoding using HEVC (H265) using the “HEVC Main 10 Profile, Main Tier, Level 5.1” profile. The encoding shall be conformant to that defined by DVB in ETSI TS 101 154 v.2.3.1 https://www.etsi.org/deliver/etsi_ts/101100_101199/101154/02.03.01_60/ts_101154v020301p.pdf
HLG10 allows the signaling of “transfer characteristics” to enhance the picture quality. However if this feature is used the picture is unable to be rendered on a standard UHD TV. Therefore to support the maximum number of devices, “transfer characteristics” shall not be used.
Note: In the case of Mezzanine streams do we want to use “transfer Characteristics” as we can control the receiving device, performing the transcode. We should be trying to deliver the highest quality video we can.
The Audio shall be encoded as 5.1 Surround sound using AC3 audio.
Subtitles if provided shall be represented as DVB-TTML (ETSI EN 303 560 v1.1.1), and delivered as a separate components within the Transport Stream. https://www.etsi.org/deliver/etsi_en/303500_303599/303560/01.01.01_20/en_303560v010101a.pdf
The following delivery mechanisms are being considered: