The Coronation of King Charles III in UHD HDR
Posted by Simon Thompson on , last updated
Last weekend, the Coronation of King Charles III and Queen Camilla took place in Westminster Abbey and Βι¶ΉΤΌΕΔ Research & Development were there to ensure that the Βι¶ΉΤΌΕΔ iPlayer UHD service and the broadcast HD service derived from the UHD production, provided the very best UHD and HD picture quality.
Βι¶ΉΤΌΕΔ R&D started working with Βι¶ΉΤΌΕΔ Events late last year to provide UHD HDR production expertise for the live Coronation programmes. We have worked over the last 6 months with the Βι¶ΉΤΌΕΔ Studios Production team, manufacturers, and our Outside Broadcast (OB) providers (Cloudbass, EMG, Timeline and Vivid) to ensure that the OB trucks coverage was of the highest technical quality. Further technical details will be published soon.
Image above of (cropped) by on , .
There were 7 OB trucks covering the Βι¶ΉΤΌΕΔ Studio, the route along the Mall, through Admiralty Arch, down Whitehall and through Parliament Square and providing coverage of the Abbey Service. We needed to ensure that they could create consistent HDR video with the same controls available for all camera operators and that all format conversions match. We've also worked with the team covering the studio complex near Canada Gate which brings together the 6 other OB truck feeds to produce the Domestic and International UHD HDR and HD feeds. In addition, we undertook testing of scaling and interlacing equipment to ensure that the images would look perfect on Βι¶ΉΤΌΕΔ One HD and the world HD feed. This task required the use of an old favourite, a specially created version of the Βι¶ΉΤΌΕΔ testcard, to ensure that the spatial and temporal filtering and the colour space down-mapping was working optimally for the task. (Please note that the image has BT.2100 colour primaries so may not display correctly on your monitor.)
The workflow was built upon the Βι¶ΉΤΌΕΔ LUT package version 1.6, an update we created last year based on feedback from vision supervisors working on live, non-sport events and tests including Glastonbury's Pyramid stage. These LUTs are designed to allow a greater creative freedom in applying colour offsets for creative intent – something not really used in the types of sports events covered previously. The workflow proved to be extremely robust with consistent images being produced by all 7 OB trucks using different cameras and different format conversion hardware.
We also managed to greatly reduce the dependence of the production on SDR signals, as we discussed previously.
- For the first time, the quick turnaround editors were recording and editing HLG for playout on the OB truck's playout servers. They were also importing archive HD and film footage and converting to HLG for inclusion in the 3 live programmes, and
- of the 100+ cameras used, only 2 were SDR cameras (in the garden of Buckingham Palace), the remainder were HDR.
Work is progressing to eliminate SDR Islands – W3C have now published a draft specification for an update to Portable Network Graphics (PNG) which will allow HLG raster images to be stored, but it's not yet available in the libraries that tools use.
During the week we spent time visiting the geographically diverse OB trucks, checking equipment settings against those we created in the lab, speaking to vision engineers and vision supervisors and working with the quick turnaround editors to ensure their process was robust. We worked hard to ensure they understood the (developed through our work on the 2019 FA Cup finals) and that they were happy with the pictures they could produce and the extra detail and colour reproduction the workflow provides.
By the time the final set of rehearsals were ending, we were in a good place. All OB trucks were working well, producing outstanding quality pictures, able to match the look of the other trucks and had a clear understanding of the workflow.
And then we were on air – 19:00 - 20:00 for the preview programme on Friday, 07:30 – 15:00 for the main event on Saturday and again at 19:00 - 20:30 for the highlights programme. The culmination of a great week, meeting colleagues old and new and taking a major set-piece to the next level, technically. The output on UHD iPlayer and the UHD World Feed was truly stunning.