Simon Thompson (BBC R&D)
The introduction of High Dynamic Range (HDR) is still the leading video topic for the EBU, especially because high-value live sports broadcasts are increasingly produced in HDR, including UEFA 2024 and the Olympic Games in Paris.
To help guarantee maximum quality, in the months leading up to these events, the EBU’s HDR Task Force held a series of dedicated EBU Members calls. These enabled technical staff to share how they were preparing for these major sports events and to identify any problem/solution early on. After both events, an evaluation was held to share experiences and impressions of the resulting image quality.
Guidance for Members
Although the workflows for live HDR (and SDR) production are now well established, wrong equipment settings can easily lead to errors. One of the most common points of misunderstanding is related to video-level ranges. Differences in working practices, devices and terminology have created room for confusion. A tutorial during this year’s EBU Production Technology Seminar, and a visual companion added to EBU Recommendation R 103 (credit to NRK), should help reduce such confusion and avoid unnecessary clipping and other quality issues.
Another point of guidance provided relates to still images, which are used for on-screen graphics, etc. Here, too, it is key to understand what format the image is created in. New metadata options in popular file formats help carry such information. A dedicated webinar (presented by BBC and NBC staff who worked to enable this) was held to explain how this works.
Monitor tests
To understand which reference displays are fit for which purposes, the EBU Video Group continues to undertake video monitor tests. A first session held earlier in the year has shown the increasing diversity in terms of product features and quality (see EBU Tech Report 081). The results of the November session will be available soon. A third testing session is already planned for Q1 2025, as several interesting new monitor models are expected to become available over Christmas.
HDR training
In October this year the EBU piloted a new hybrid HDR training with Turkish EBU Member TRT. Our goal was to help the broadcaster prepare for in-house HDR productions by increasing its staff’s HDR knowledge, especially covering the use of Closed Loop Shading, LUTs, and how to verify signals. The pilot turned out to be great success, not the least because of the curious, interactive attitude of the participants. A wealth of knowledge was shared by trainer Hector Sole-Bradshaw Beltran, with support from the author.
The training is now part of the EBU Academy offering – for more information, contact Hélène Rauby-Matta.
Upcoming work
Besides more HDR monitor testing, the EBU Video Group’s work for 2025 includes work on cameras, codecs, HDR QC tests, test material, interlacing, and fresh data on EBU Members’ UHD/HDR strategies.
The legacy of interlacing is an interesting topic, as we are now in a situation where it – ironically – has become harder to create a good interlaced image, partly because (new) equipment does not always implement interlacing optimally and partly because the progressive source images have become so good that the limitations of the interlaced HD format are becoming painfully clear. For more information, or to join the group, see: tech.ebu.ch/video
This article first appeared in the December 2024 issue of tech-i magazine.