HDR is becoming the standard for premium live production, delivering sharper images and improved contrast without increasing bandwidth requirements. For live contribution, this enables efficient workflows and reliable signal delivery across complex broadcast and streaming chains.
When Ultra HD was first suggested, all the hype went to 4k resolution, not least because it is easy to market. But moving to 4k requires a lot of investment from glass to glass. It also quadruples the bandwidth requirements when moving from 1080p to 2160p, as progressive scanning is typically used, which increases the bandwidth demand.
Content creators and broadcasters have moved to a much more practical and pragmatic way of boosting the viewer experience: HDR – high dynamic range video. By smart management of the eight bits per pixel we can increase the perceived color fidelity: blacks can be blacker; whites whiter.
The more subtle, but more important, benefit is that more precise discrimination of light levels makes a sharper image. You may not recognize the color difference between two adjacent pixels, but you will certainly see crisper definition and smoother gradients.
HDR gives a boost to definition not dissimilar, in user experience, to 4k, but for a lot less bandwidth.
HDR increases the perceived color fidelity, resulting in a sharper image and improved contrast
That is why we are seeing a lot of production companies and broadcasters rapidly adopting HDR on conventional HD coverage. This is particularly true of premium sports coverage, the highest value live television, where HDR is now the norm. And that is why we have to consider the challenges – if any – of moving those signals around.
A host broadcaster at a sports event has three options for the signals it offers to rights-holding broadcasters taking the feed. It can go for traditional, SDR HD. It can produce and deliver in 10-bit HDR. Or it can encode that 10-bit origination into an 8-bit signal.
BBC and NHK jointly developed HLG, which is a standard for transporting both SDR and HDR signals over live contribution links, and for the broadcasting of HDR originated content. HLG is hybrid log-gamma, a mathematical algorithm that uses the traditional SDR broadcast gamma transfer curve for the lower part of the signal, but a logarithmic function for the upper part of the signal.
This retains much of the additional detail without visible distortion or banding. It also means it is backwards compatible with SDR equipment, including modern displays. That is important, because it means production companies only need to create one output.
What does this mean for contribution circuits, like the Intinor Direkt? For simple and reliable workflows, the hub at the production end has to be capable of recognizing and receiving SDR and HDR HLG streams. It must preserve the signal flags and metadata that tell downstream devices what format is being sent and how to interpret it.
If you have been in the business, 20 years ago you will remember the move from 4:3 to 16:9, and the importance of preserving the widescreen flag when moving signals. This is pretty much the same.
Modern processing means we can transmit HDR HLG signals, in broadcast quality and reasonable latency, in modest bandwidths. If you have 15 Mb/s then you are good to go.
Premium content will increasingly be made in HDR. Dramas will use the extended color gamut to create moods; major sports love the crisp resolution and audience engagement; esports fans will expect to see the same level of detail as they would if they were playing the game themselves. At Intinor we make this happen.
If you’re working on HDR-enabled content and want to ensure flawless delivery across your broadcast workflows, you can talk to us. Our solutions are designed to seamlessly integrate with your existing setups and help you deliver the highest quality content with confidence.