DPP TECHNICAL SPECIFICATION FOR DELIVERY OF SD COMMERCIALS & SPONSORSHIPS TO CHANNEL 4 SALES This document is a complete guide to the common technical specification, agreed by ITV, IMD and Adstream, and Channel 4 Sales (for Channel 4, and on behalf of BT Sport, Box TV and UKTV.)
Version 1.0
This document is a complete guide to the common technical specification agreed by Channel 4 Sales, ITV, BT Sport, IMD, and Adstream.
The first four pages of this document outline parts of the specification that are unique to Channel 4 Ad Sales The main body of the document outlines the specification as adopted by the above parties.
The Specification includes:
Technical Specifications, i.e. the technical production methods which must be used, and the parameters which all material must meet to be acceptable by the broadcasters.
Picture and Sound Quality requirements, which also form a binding obligation on producers of material. Assessment of quality is by nature subjective, and is highly dependent on the nature of the commercial or sponsorship. Some of the Quality Requirements are expressed in relative terms (“reasonable”, “not excessive” etc.), and it will be necessary to make a judgement as to whether the quality expectations of the intended audience will be fulfilled, and whether the broadcaster will feel that value for money has been achieved.
Delivery Requirements, which specify the form and layout of the material.
Sponsorship Delivery
This Technical Specification outlines the full details for SD Commercial delivery as well as relevant elements for SD Sponsorship material, however it must be noted that Sponsorship clock numbers, file naming conventions and approval processes differ from commercials and are broadcaster- specific. Please see the broadcaster section of this specification for sponsorship delivery details.
Material submitted for transmission must satisfy the IMD/Adstream Quality Control process. Material failing the QC process may be rejected and returned to the supplier for repair.
Please ensure you are using the current version of this document, available at: https://www.channel4sales.com/planning-and-buying/Specs/on-air-specs-and-delivery/
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COMMERCIALS: Every commercial submitted for transmission must satisfy a Quality Control process outlined by the parties above. Any commercial failing the QC process may be rejected and returned to the supplier for repair. Please ensure you are using the current version of this document, available at: https://www.channel4sales.com/planning-and-buying/Specs/on-air-specs-and-delivery/
For any queries relating to the specification and delivery of copy please contact your Traffic Manager:
Traffic Kim Wakes – [email protected] 020 7306 8264 Traffic Manager Matt Gustard – [email protected] 020 7306 8266 Deputy Traffic Manager
Normal route for delivery to Channel 4 Ad Sales: The Producer gets the copy cleared for broadcast by ClearCast. The Producer is then responsible for sending the file to Adstream or IMD. Once Adstream or IMD have received and completed the Q.C. for the copy, they deliver it to video servers based at the play-out providers for all channels listed.
SPONSORSHIPS:
IDENTIFICATION: Sponsorship copy is identified by unique clock numbers, obtained from C4 Sponsorship Department Account Managers. Without this number, the material will not be transmitted.
For File-delivered Copy: FILENAMES should follow the unique Clock Number assigned to it, in UPPERCASE, with the extension “.mxf” in lowercase. Allowable characters are ‘A-Z’, ‘0-9’, ‘-‘ & ‘_’ , so the underscore is used where a forward-slash might be referred to. Here is an example: C4S/HOTPOT16014/005 Becomes C4S_HOTPOT16014_005.mxf
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SPONSORSHIP CONTACTS
For any queries relating to the specification and delivery of SPONSORSHIP copy please contact one of the following:
Traffic Kim Wakes – [email protected] 020 7306 8264 Traffic Manager
Matt Gustard – [email protected] 020 7306 8266 Deputy Traffic Manager
Clare Williams - Senior Airtime [email protected] 020 7306 5521 Executive Lisa Aldred - Senior Airtime [email protected] 020 7306 3741 Executive Matthew McCue Digital Media Manager [email protected] 020 7306 8352 BOX TV ONLY
There is also a generic e-mail for all clients: [email protected]
SPONSORSHIP - MUSIC REPORTING
In addition to the delivery of your material to IMD or Adstream, there is an additional requirement for Channel 4 itself.
Channel Four is contractually obliged to report all music broadcast. Music details must be supplied with all delivery material, emailed to [email protected]. If no music is used, this should be stated in the email.
For commissioned music: For other music: Music title Music title Composer Composer Publisher Performer Duration Arranger Publisher Record Company Catalogue Number Track Number Usage (background or featured) Duration
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Contents
1 INTRODUCTION ...... 6 2 GENERAL QUALITY REQUIREMENTS ...... 7
2.1 PICTURE QUALITY ...... 7 2.2 SOUND QUALITY ...... 8 2.3 SUBTITLES AND AUDIO DESCRIPTION (A.D.) ...... 8 3 FILE DELIVERY REQUIREMENTS ...... 9
3.1 FILE DELIVERY FORMAT – STANDARD DEFINITION ...... 9 3.2 TIMELINE OF A COMMERCIAL ...... 9 3.3 THE IDENT CLOCK OR SLATE ...... 10 3.4 IDENTIFICATION ...... 10 4 TECHNICAL REQUIREMENTS – VIDEO ...... 11
4.1 STANDARD DEFINITION VIDEO CODEC ...... 11 4.2 STANDARD DEFINITION IMAGE FORMAT ...... 11 4.2.1 Origination ...... 11 4.2.2 Post-production ...... 11 4.2.3 Field dominance ...... 12 4.3 VIDEO LEVELS AND GAMUT (ILLEGAL SIGNALS) ...... 12 4.3.1 Measuring signal levels ...... 12 4.3.2 Tolerance of out of gamut signals ...... 12 4.4 ‘BLANKING’ ...... 12 4.5 ASPECT RATIO ...... 13 4.5.1 Non-standard Aspect Ratios (“letter-boxing”) ...... 13 4.6 PHOTOSENSITIVE EPILEPSY (PSE) ...... 13 4.6.1 Testing for flashes and patterning ...... 13 4.7 CAPTION LEGIBILITY ...... 14 4.8 CAPTION-SAFE AREA ...... 14 4.8.1 16:9 Caption Safe Area in the SD Environment ...... 15 5 TECHNICAL REQUIREMENTS – AUDIO ...... 16
5.1 TERMS, REQUIREMENTS AND GUIDELINES ...... 16 5.1.1 Guidelines for True Peak audio levels ...... 16 5.2 METERING REQUIREMENTS ...... 17 5.3 STEREO AUDIO REQUIREMENTS ...... 17 5.4 AUDIO FORMAT ...... 17 5.4.1 Track allocations ...... 17 6 XML METADATA SET ...... 18 APPENDIX 1 – FILE, VIDEO & AUDIO CHARACTERISTICS ...... 19 APPENDIX 2 – VERSION CONTROL ...... 19
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1 Introduction
Commercial & Sponsorship copy is delivered by file only. Where the word “commercial” is used herein, it may also mean “sponsorship”
Once submitted, files will not be retrievable, so it is highly recommended that the producer retains their own copy of the file.
This specification defines the delivery from the commercials suppliers listed below to the Broadcasters, and not from the advertising-copy producers. Adstream http://www.adstream.com +44 (0)20 7539 8400
IMD UK Ltd www.imdplc.com +44 (0)20 7468 6868
Delivery on Tape: Tape delivery to the above suppliers is no longer permitted without prior agreement with them.
Currently Adstream and IMD produce their own delivery specifications from the advertising copy producers to themselves, together with delivery details.
All commercials are currently delivered to the Broadcasters in Standard Definition (SD) only to any Broadcaster listed, even if they were produced in HD or even higher formats.
Commercials must conform to the current BCAP Television Advertising Standards Code. (Broadcast Committee of Advertising Practice).
All commercials intended for transmission on any of the services listed on the front page of this document must be approved by Clearcast.
www.clearcast.co.uk
All commercials delivered by file will be a single Media file per single item, with associated XML file.
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2 General Quality Requirements
2.1 File Delivery Format – Standard Definition There may be other statements about aspects of file format in this document. However, the following paragraph shall be the normative definition of the file format for DPP SD Commercials.
The file format used for this DPP SD Commercials specification shall be based on as that specified by the UK DPP SD Shim of AMWA AS-11 version 1.1 (http://www.amwa.tv/projects/AS-11.shtml), with the following changes: 1. A file shall not contain the Descriptive Metadata Tracks and Segmentation Track (and associated Descriptive Metadata Schemes and Frameworks) described in AS-11. 2. The metadata is to be delivered as a separate xml file as described in section 6 3. The UK DPP SD Shim constraint on the presence of Closed Captions (out-of-vision subtitles) is lifted. 4. There is no line-up / tone present
2.2 Picture Quality
The picture must be well lit and reasonably but not artificially sharp. The picture must be free of excessive noise, grain and digital compression artefacts. The picture must be free of excessive flare, reflections, lens dirt, markings and obstructions (e.g. lens hood), and lens aberrations. Movement must appear reasonably smooth and continuous, and must not give rise to distortions or break-up to moving objects, or cause large changes in resolution. The picture must be free of excessive black crushing and highlight compression. Hard clipping of highlights (e.g. by legalisers) must not cause visible artefacts on screen. There must be no noticeable horizontal or vertical aliasing, i.e. jagged lines, field or frame rate fluctuations in fine detail. Colour rendition, especially skin tones, must be consistent throughout, and a realistic representation of the scene portrayed unless it is altered as an editorially essential visual effect. The picture must be stable and continuous - i.e. no jumps, movements, shifts in level or position. There must be no visible contouring / artefacts caused by digital processing. Quantisation noise must not be apparent. There must be no noticeable spurious signals or artefacts e.g. streaking, ringing, smear, echoes, overshoots, moiré, hum, cross-talk etc. Note: EBU R118 is used to assess the suitability of cameras for HD use (if the commercial is produced in HD). In case of doubt please contact your broadcaster
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2.3 Sound Quality
Sound must be recorded with appropriately placed microphones, giving minimum background noise and without peak distortion. The audio must be free of spurious signals such as clicks, noise, hum and any analogue distortion. The audio must be reasonably continuous and smoothly mixed and edited. Audio levels must be appropriate to the scene portrayed and dynamic range must not be excessive. They must be suitable for the whole range of domestic listening situations. Stereo audio must be appropriately balanced and free from phase differences which cause audible cancellation in mono. The audio must not show dynamic and/or frequency response artefacts as a result of the action of noise reduction or low bit rate coding systems.
2.4 Subtitles and Audio Description (A.D.)
The Equalities Act 2010 (formerly the Disability Discrimination Act) requires service providers to take positive steps to make their services accessible to people with disabilities. It states that where a service provider offers or provides services to members of the public, the provider will have to take such steps as is reasonable to make it easier for disabled people to make use of the service. Broadcasters are service providers and this therefore applies to them. (DCMS Guidance 2006) Commercials suppliers are therefore required to consider the needs of people with hearing or visual impairments while generating captions, subtitles and graphics, using voiceovers, and while mixing sound. The Communications Act 2003 sets targets for broadcasters (monitored by Ofcom) to provide subtitling, sign language and audio description services, so commercials suppliers may be asked to provide appropriate additional material. For further information, please refer to the appropriate technical contact on the front page of this document.
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3 File Delivery Requirements
3.1 File Delivery Format – Standard Definition
This section covers the requirements for transmission-ready SD files. All commercials must be delivered as files and must comply with all the relevant video and audio requirements below. The key standards are the MXF file wrapper (SMPTE 377M-2004 and additions) and its Operational Pattern OP1a (SMPTE 378M-2004) (Single Item Single Package). Each commercial should be delivered as a single principal MXF file containing the audio and video. There must be only one commercial in each file. A single commercial will always be played out from start point to end point without interruption. IN- point and DURATION for the continuous playback section must be included with the delivery metadata. As per the diagram below, “DURATION” does not include the five-second hold.
3.2 Timeline of a Commercial
7 sec 3 sec mm:ss (Duration of Essence) 5s 1 2 3 4 5 6 7 8 9 0 0 0 0 0 0 0 0 0
: : : : : : : : :
s 0 0 0 0 0 0 0 0 0 s 0 0 : 0 0 0 0 0 0 0 0 0 0 1 : : m 0 0 0 m 0
Clock or BLACK Vision - Active Part Vision Hold Ident 3secs (Active on-air duration, exact number of mm:ss) 5 Seconds 7 secs E E
C Audio C N N
SILENCE E 6 frames shorter than the video at either end. E SILENCE L L I I S S
(6 frames of silence before – and 6 frames of silence after) f f 6 6 t t r r a a t t S S
e e l i Duration m F m a r g o r P
All commercials delivered on file must be laid out so that the start of the material is at timecode 00:00:10:00 as specified in the MXF Material Package timecode track. VITC timecode should not be present There should be 6 frames of audio silence at the start and end of the item and the duration should not exceed the stated length. At the end of the item there should be a 5 second hold on vision, completely still (No ‘Living Freezes’ or animations). Note that it is usual for sound and vision to be automatically cut to air on transmission, so early vision or sound is not normally required. Vision may fade up from black starting at 00.00.10.00 if desired. Earlier specifications called for 30 seconds of black at the end. This requirement has been removed.
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The Ident Clock or Slate
Advertising copy requires a unique identifier supplied by the advertising agency and approved by Clearcast.
For all copy: A clock or slate is to precede each item for a duration of 7 seconds. The clock should identify:
Product name Identifier/Agency copy number (clock number) o Commercial item duration o If subtitles are present, WST. Black and silence should exist for 3 seconds between the clock and the first frame of picture. Note: The start of material is measured from the first frame of active picture. Vision fade-ups are acceptable - in which case the first non-black frame is taken to be the start of material.
3.3 Identification
IDENTIFICATION: Commercial copy is identified by unique clock numbers, obtained from the agencies and approved by Clearcast. “Clock numbers” are denoted in metadata as “Material_ID” Without this number, the material will not be transmitted. FILENAMES should follow the unique Clock Number assigned to it, in UPPERCASE, with the extension “.mxf” in lowercase. Allowable characters are ‘A-Z’, ‘0-9’, & ‘_’ The underscore is used where a forward-slash might be referred to. Here is an example:
CTS/HXFA321/030 Becomes CTS_HXFA321_030.mxf (Please note the use of under-scores, not hyphens).
The filename of the associated metadata xml shall have the same naming convention e.g. CTS_HXFA321_030.xml
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4 Technical Requirements – Video
4.1 Standard Definition Video codec
(The video essence is identical to the essence described by the UK DPP/AS-11 specification). The video essence in the file must be encoded at a nominal bitrate of 50Mbit/s using the Type D10 MPEG2 4:2:2P@ML (SMPTE 356M-2001) stream specification, I-frame only. This is a constrained version of MPEG-2 4:2:2 P@ML (constrained bytes per GOP). The essence mapping should be D-10 in a generic OP1a MXF container in accordance with SMPTE 386M-2004.
4.2 Standard Definition Image format
Although many UK broadcasters require High Definition (HD) delivery for new programme content, this is not currently the case for advertising content. For now, all commercials delivered for UK transmission must be delivered in Standard Definition (SD).
All commercials delivered for UK transmission must be in Standard Definition only, with an active width of 720 pixels. SD video files must be recorded with a picture area of a minimum 702 x 576 pixels (SMPTE 386M-2004), where the 702 pixel wide picture must be centred in the active 720 pixel wide line. (Digibeta Legacy). The picture information may extend to the full width of the 720 pixel wide line, providing the image shape is not distorted. The active video resolution is therefore 720 x 576 (SMPTE 386M-2004). In either case there must be an additional 32 lines corresponding to a Vertical Blanking Interval (VBI) making a total of 720 wide x 608 high. The VBI must not contain any data or image, save for any subtitle data. The frame-rate must be 25 frames per second (50 fields) interlaced, known as 576i/25, with colour sub-sampled at a ratio of 4:2:2. The SD format is fully set out in ITU-R BT.656
4.2.1 Origination
Material may be originated with either interlaced or progressive scan.
4.2.2 Post-production
Electronically generated moving graphics and effects (such as rollers, DVE moves, wipes, fades and dissolves) must be generated and added as interlaced to prevent unacceptable judder.
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4.2.3 Field dominance
Cuts in material must happen on frame boundaries (i.e. between field 2 and field 1). Motion on psf material must always occur between field 2 and field 1 (i.e. field 1 dominance).
4.3 Video Levels and Gamut (illegal signals)
Video levels must be received within the specified limits so that the material can be used without adjustment. Any signal outside the specified limits is described as a gamut error.
4.3.1 Measuring signal levels
Digital video levels are usually measured with a device which displays a trace like a traditional waveform monitor. This gives readings in mV (emulating an analogue signal), or as a percentage of the allowable levels. The limits of signal levels are defined by reference to a nominal black level and a nominal white level. Black level comprises R, G and B, all at zero (or 0% or 0mV) and white level is all three components at 100 % or 700mV. In a picture signal, each component is allowed to range between 0 and 100% (or 0mV and 700mV). This equates to digital sample levels 16 and 235 (8-bit systems) or 64 and 940 (10 bit systems).
4.3.2 Tolerance of out of gamut signals
In practice it is difficult to avoid generating signals slightly outside this range, and it is considered reasonable to allow a small tolerance, which has been defined as follows under EBU Rec103: RGB components must be between -5 % and 105% (-35 and 735mV) And Luminance (Y) must be between -1% and 103% (-7mV and 721mV) Slight transient overshoots and undershoots may be filtered out before measuring, and an error will only be registered where the out of gamut signals total at least 1% of picture area. Many monitoring devices are designed to detect errors to this specification.
4.4 ‘Blanking’
A two-pixel tolerance will be permitted during CG or complex overlay sequences where key signals, graphic overlays or other effects do not fully cover the background image. Where animated key signals or overlays cause moving highlights at the edge of the active image it is preferable to blank these pixels completely.
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4.5 Aspect Ratio
The aspect ratio must be 16:9 Full Height Anamorphic and can be shot 16:9 Action Safe. This means that the active picture must fill a 16:9 screen vertically and horizontally without geometric distortion.
4.5.1 Non-standard Active Picture Ratios
In the case of the active picture ratio not being 16:9, such as 2:39:1, 2.35:1 (21:9) or 1.85:1, the picture should be centred vertically between black bars in a 16:9 frame, filling the height of the frame, and with no geometric distortion. Note however, that some widescreen consumer TV sets operating in Auto Zoom / Auto mode often interpret large black borders at the top and bottom of the screen as letterbox, so are likely to enlarge the picture. The resulting unpredictable zooming can be annoying for the viewer and undermine the artistic intent.
4.6 Photosensitive Epilepsy (PSE)
Flickering or intermittent lights and certain types of repetitive visual patterns can cause serious problems for viewers who are prone to photosensitive epilepsy. Children & teenagers are particularly vulnerable. All UK Television channels are subject to the Ofcom BROADCASTING CODE Issue Ten (2012), which states: Section 2: Harm and Offence Guidance: 2:12 Flashing images and/or patterns can cause seizures in people with photosensitive epilepsy. The Ofcom guidelines, based on scientific research, are intended to limit the incidences of seizures and a warning should only be used in place of the guidelines if editorially justified. The Ofcom guidance is at: http://stakeholders.ofcom.org.uk/binaries/broadcast/guidance/831193/section2.pdf
4.6.1 Testing for flashes and patterning
Commercials for file delivery must be tested using any file based PSE device that meets the guidance given by Ofcom. The DPP maintains a list of approved devices, available at: http://www.digitalproductionpartnership.co.uk/downloads/standards/ Under “PSE Devices”
Broadcasters will, at their discretion, either test the commercial during the Quality Control process, or will require a pass certificate to be delivered with the commercial.
Test certificates for file delivered commercials must be in pdf form, and will be retained by the agency who delivered the commercial to the broadcaster. The relevant metadata details must be completed (see the relevant Metadata spec in this document) Any failure whatsoever will result in rejection of the commercial, and any affected sections must be repaired and re-tested before acceptance.
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4.7 Caption Legibility
Captions must be clear and legible and must be within the safe areas specified. Text which is there for legal or regulatory purposes (the “small print”) must comply with BCAP Guidelines. Height is measured using flat-topped letters, where possible, e.g. “v”, “w” or “x”. If there is both upper and lower case lettering the lower case letter will be used to determine text height. BCAP Guidelines state that the minimum text height is 16 television lines, except where there is a solid single-coloured background when the text height can be 14 lines. There is also further guidanceon the Clearcast website: http://kb.clearcast.co.uk/wiki/35/supers-test-card
4.8 Caption-Safe Area
There is now only one caption safe area defined for 16:9 material for UK transmission: “16:9 Caption-Safe”
SD Production
Caption Safe Area Defined as (%) SD pixels (inclusive) Vertical TV line numbers (inclusive) first pixel numbered 1 numbering as per “Rec601”
SD 16:9 Caption safe 80% of Active Width Width: 79 – 640 inclusive 90% of Active Height Height: 30 – 547 inclusive 38 to 295 (F1) and 351 to 608 (F2)
The total number of lines is 625 (active lines from 23 to 310 and 336 to 623 inclusive = 576 lines).
HD Production
Caption Safe Area Defined as (%) HD pixels (inclusive) TV line numbers (inclusive) first pixel numbered 1 numbering as per “Rec709”
HD 16:9 Caption safe 80% of Active Width 191 – 1726 90% of Active Height 55 – 1026 48 to 532 (F1) and 611 to 1095 (F2)
The total number of lines is 1125 (active lines from 21 to 560 and 584 to 1123 inclusive = 1080 lines)
At the discretion of the broadcaster, some commercials may be excluded from this requirement.
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4.8.1 16:9 Caption Safe Area in the SD Environment
If producing in SD - or when down-converted to SD NOTE: Below is an anamorphic image shown stretched to 16:9 raster.
Pixel 1 Pixel 30
16:9 Caption Safe Area
Pixel 1 Pixel 79 Pixel 640 Pixel 720
Pixel 547
Pixel 576
If producing in an HD Environment…
Pixel 1 Pixel 55
16:9 Caption Safe Area
Pixel 1 Pixel 191 Pixel 1726 Pixel 1920
Pixel 1026 Pixel 1080
Note that whichever domain of SD or HD is used for production or delivery, the areas are the same so this check need only be done once.
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5 Technical Requirements – Audio
5.1 Terms, Requirements and Guidelines
The measure of Audio is based on R128. The terms used in this document, how they are measured and the DPP delivery requirements are listed below.
All commercials must be compliant with the Material Loudness and Maximum True Peak requirements below.
Other parameters are currently given for guidance only.
Term Description Measurement Reference LU Loudness Unit 1LU = 1dB EBU Tech 3343 change in loudness LUFS Loudness Unit relative to LUFS EBU Tech 3343 Full Scale LRA Loudness Range LU EBU Tech 3342
DPP Delivery Requirements Term Description Measurement DPP Requirement Programme The maximum* loudness LUFS Non-live Loudness measured over the -23.0 LUFS ±0.5LU (EBU Tech 3343) duration of the Live -23.0 LUFS ±1.0LU commercial. Maximum True Peak The maximum value of the dBTP (True It is recommended that the maximum true (EBU Tech 3343) audio signal waveform. Peak) peak level should not exceed - 3dBTP. Content will fail if the maximum true peak exceeds -1dBTP
* Although the target loudness is -23 LUFS, in exceptional circumstances lower target levels may be permitted by agreement with the broadcaster.
5.1.1 Guidelines for True Peak audio levels
The following table is only for guidance on the true peak levels of different types of audio. At all times dialogue should be distinct and clear.
Material Recommended Maximum Peaks Uncompressed Music -3 dBTP Compressed Music (depending on degree of compression) -10 dBTP Heavy M & E (gunshots, warfare, aircraft, loud traffic, etc.) -3 dBTP Background M & E (office/street noise, light mood music etc.) -18 dBTP
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5.2 Metering Requirements
Meters must comply with the specifications in EBU Tech 3341. Commercials must be measured using the EBU Integrated (I) mode and the measurement must be applied to the whole commercial (EBU Tech 3343 Section 5).
5.3 Stereo Audio Requirements
Stereo sound is the expected standard for commercials transmission on all channels. Stereo tracks must carry sound in the A/B (Left/Right) form. Surround Sound is not permitted. Advertising copy that is not stereo should be delivered with phase coherent mono sound on both audio tracks, so that it may be handled exactly as stereo. It must meet all the stereo standards regarding levels, balance and phase. Stereo audio must be capable of mixing down to Mono without causing any noticeable phase cancellation.
5.4 Audio Format
The audio must be frame interleaved with the video within the OP1a file as described by AS-11 (SMPTE 386M-2004). All audio tracks must be encoded as linear PCM in an AES3 (SMPTE 331M) stream with a sample rate of 48kHz at a depth of 24bits/sample.
5.4.1 Track allocations
The file should have transmission audio on tracks 1 and 2, and be in synchronism with the vision. SD files must contain 2 or 4 tracks encoded as PCM, as below:
Tracks 1&2 – main stereo audio Tracks 3&4 – AD where present Tracks 5-8 – are necessarily present, but should be unused and contain digital silence The unused audio tracks in the 8 track groups above must contain digital silence and encoded as PCM audio. For compatibility with stereo systems, any audio generated as mono must be presented on two phase-coherent tracks, and flagged as stereo. The naming conventions used in all related documentation and metadata must match those specified above.
EBU Reference Prog Type 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
code
St. St.
R48: 2a Stereo Final Final Silence Mix L Mix R Silence
St. St. Stereo with St. St. Aud Aud R123:4c Audio Final Final Desc Desc Description Mix L Mix R L R
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6 XML Metadata Set
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Appendix 1 – Version Control
UK DPP VERSION
REQUIRED / VERSION DATE SECTION UPDATE INFORMATION
First iteration
UK 1.0 17/03/2015
Channel Four VERSION
REQUIRED / VERSION DATE SECTION UPDATE OWNER INFORMATION
Channel Four 1.0 04/06/2015 Broadcaster Specific Required First version of specification issued PG
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