File Delivery: SportTech ‘DPP in Sports’ panellist Mark Hill previews issues to be debated on May 7
SVGEurope’s upcoming SportTech Europe summit at Emirates Arsenal FC on May 7 will feature a panel discussion titled ‘Delivering to Spec: Effects of the DPP as-11 on Sports Production.’ Mark Hill, Managing Director, Ixedia, is a panellist at this important session and here he takes us through some of the big file-based delivery issues that will be debated on the day.
1 October 2014 marks an important landmark in UK broadcasting, namely File Delivery Day (FDD). This is the date by which the major UK broadcasters will officially begin receiving programme deliveries as files. In developing what is a comprehensive and very accessible standard, the principal UK broadcasters in DPP have all agreed to ditch videotape and their hitherto individual delivery idiosyncrasies and adopt a harmonised, IT-friendly way of doing things.
So, variations along the lines of: ‘I want this programme on Sony HDCAM SR with pre-programme line-up formatted like this…’, and: ‘I want my audio formatted like that…’, will soon be no more. No longer will programme suppliers and post houses have to maintain multiple different configurations for formatting deliveries to these broadcasters. UK ‘DPP AS-11 Technical Standards For Delivery of Television Programmes’, to give it it’s full name (now at version 4.1) is a single document made out of much input from end users and one which, sensibly, leans on a number of other proven industry standards.
Version 4.1 of the AS-11 standard provides for delivery of metadata accompanying the audio-video essence to be packaged exclusively within the MXF wrapper. In some prior versions of the standard, a mandatory XML sidecar file was required per delivery, which contained mostly metadata that duplicated that in the MXF file with a few minor additions. Doing away with these provides for a one-stop export of essence plus metadata direct from post production, rather than making the essence in a non-linear edit (NLE) system and then wrangling the metadata in another system further down the workflow.
One difference between what is possible with a videotape and a file that is worth highlighting is that there is currently no ‘insert edit’ equivalent in the file-making process. So, should for example, you happen to mistype the programme/version number when making up the ident clock at the head of the programme in your NLE such that this fails to agree with the Production Number subsequently baked in the metadata, then, not only will you need to make a (repair) edit, but re-delivery will entail a re-export of the entire MXF file. It is not inconceivable that an insert edit feature may be forthcoming in future outings of AVC (intra-frame coded pictures) and MXF wrapper but, for the time being, getting AS-11 deliveries right first time is very important, especially for content types where time to air is ‘of the essence’.
What about ‘short-form’?
Historically, broadcasters have started their journeys to file-based playout operations in the short-form world — commercial spots; promotions (trailers); presentation kit (bumpers, idents, stings,…) etc. Remember, video servers once sported storage capacities on a par with what most of us now carry around in the form of a memory stick in our pockets! Against this background, it therefore seems at first somewhat odd that DPP has chosen to focus its combined might at programme duration content. Their decision is however quite understandable, programme delivery is after all the meat in the pie. Besides, broadcasters have long since made adequate local arrangements for handling their own short-form content as files.
A suitable standard for short-form is on the roadmap for DPP to address. A logical time for a short-form standard to be in place would be when delivery of file-based commercials moves to HD. Years ago, the UK industry was successful in getting the necessary parties around the table to set a date for ‘C-day’ – when commercial spot delivery transitioned from 4:3 coded frame pictures to 16:9. Some similar ‘big bang’ style date for transitioning spot delivery from SD to HD is possible and desirable, not least because advertisers want their commercials to look their best on screen against surrounding other material and that it generally now costs more to turn content invariably produced in HD back into SD for distribution.
One broadcaster has already investigated ‘bending’ the AS-11 standard to assess its usability for short-form content. Unsurprisingly it worked however, under the version three standard, appending two minutes worth of line-up and ident onto the front of every sub-10 second clip was not popular! Version 4.1 of the AS-11 standard has reduced the mandatory pre-programme line-up to 30 seconds, however even this represents a major overhead in relation to the typical durations of short-form.
One possibility for a future short-form standard would be to ‘bend’ use of the basic Operational Pattern (OP) 1a, single material package/single file package in an MXF wrapper. There will be some reading this that will remember the days of laying up promotions on one minute boundaries down the length of a videotape and (pre-video server) playing out these individual items by means of a tape ID, plus start of message and duration timecode. Carrying over such a practice into file-based world is not quite as illogically retro as it first sounds, as many promo production workflows still work with multiple versions on a single timeline in post-, rather than maintaining an individual timeline per version.
It’s not unusual, however, for promo versions to be frequently remade quite close to the date and time of transmission. Tracking replacements for promo versions delivered originally as part of an ‘pseudo programme’/’pseudo OP1a’ AS-11 comp(ilation) file and subsequently replaced in the form of a single item in a single file would be a challenge. The lack of an ‘insert’ edit into file and general unease from engineering about bending rules may kill such an approach dead.
Most broadcasters delivering short form as files will have already devised ‘sidecar’ metadata systems based on text, or XML exports to convey the essentials relating to each short-form, one per file. As such, automated workflows are likely to have already been configured to process this bespoke data, so reconfiguring to some yet to be agreed industry wide standard may be more of a challenge than moving from paper to electronic delivery data was for programmes. Attempting further harmonisation between promo etc and commercial spot content adds a further dimension to the challenge as broadcasters and playout service providers often maintain separate workflows for each.
We await further developments in this area with keen anticipation. It really is important for the industry that we continue to move to a smaller number of more widely shared ‘fit for purpose’ operating standards. The more we boil our requirements down, the greater chance we have of encouraging equipment manufacturers to commit precious research and development effort that will deliver specifically what we need to improve operations.
Quality – controlled
One crucial area that DPP has addressed recently is that of Quality Control (QC). With an eye to work ongoing in EBU, DPP has now identified precisely those criteria that will be examined as part of the process of technical acceptance of a (recorded) programme. This is of course motivated by the desire to regularise and automate as much of the acceptance process as possible. The DPP QC criteria may be divided into three types: File integrity; Auto AV and Manual AV.
In fast turnaround environments, such as news and sports production, the scale of the challenge of a formal full QC is significant. To date, getting content to air fast has resulted in the rigour of QC sometimes being relaxed towards the limit of ‘will it playback? Is the quality acceptable? Do we need to broadcast any accompanying messages (warnings)?
As an industry we would all like to do better than this minimum and it is important to recognise that, in file-based world, there is much that needs to be got right beyond that which can be superficially seen and heard in a busy gallery. Often the copy of content that gets aired is the same copy that gets committed to the library/archive for future re-use, so broadcasters cannot afford to discover weeks or months after the initial airing that, while the content played back fine on first transmission (TX) on one system, the file contains some latent structural defect that prevents it being played back at some other time on some other system.
This raises questions like: ‘Should we do QC after first TX if time is tight?’. Will the producer want paying on the basis of us having ‘accepted’ it as fit for TX, but before we have accepted it by formal QC?’. Some, all, or none of these issues might well be debated at the SportTech Europe event on 7 May in London, in the session: Delivering to Spec: Effects of the DPP AS-11 on Sports Production. I hope to see you there!