The drive towards enabling more natural, compelling and immersive viewing experiences has been a key differentiator for operators in our industry ever since the first television was switched on. The need for continuous picture quality improvement can be seen in the evolution from the era of black and white through to the introduction of color, high definition (HD), and ultra-high definition (UHD) content.
In recent years, the picture quality experience bar has been set even higher. The gradual transition from standard dynamic range (SDR) to high dynamic range (HDR) has helped deliver a clearly visible improvement in picture quality for both HD and UHD content. Its popularity is starting to soar; 2017 ABI Research forecasts that HDR capable Television set shipments will reach 245 million sets by 2022.
Lack of clear HDR direction has slowed UHD
Nevertheless, challenges around HDR and its adoption are ever-present. Discussions remain over what constitutes ‘good’ high dynamic range, and what the necessary bit depth should be. Although the amount of HDR content viewed on catch-up and on-demand services is starting to increase, live HDR content has yet to reach real critical mass. However, as both SDR and HDR content (video and advertisements) are present in an operator’s service line-ups and to ensure consumers receive a seamless, high quality experience, SDR and HDR content must coexist together.
Relying on the television to switch modes between HDR to SDR (or vice-versa) depends on the television switching without delay or failure (if there is a missing or incorrect signal) and this doesn’t always happen. This issue is further compounded when there are multiple SDR and HDR changeover points happening in rapid succession. For consumers, this can mean a less than ideal viewing experience and could potentially lead to an increase in support calls and in extreme cases, to subscriber churn.
An age-old challenge in a modern context
— MediaKind (@Media_Kind) April 11, 2018
According to my MediaKind colleague, Matthew Goldman (see video in the tweet above), the challenges are reminiscent to those once faced with the transition from SD to HD. HD channels that ran SD content (such as news inserts and advertisements) would often change mode to display incorrect aspect ratios or other types of artefact. In today’s context, when a program is seen on an HDR TV in SDR mode, the SDR content will display too brightly and wash out other colors. Conversely, when an SDR channel is delivering HDR content, the display becomes far too dark and content can be missed. These inconsistencies can ruin the overall viewing experience.
As operators seek to protect their brand, encourage advertising revenue and retain viewership in the face of competition from the likes of Netflix, this uncertainty over switching becomes an issue. Not only does it undermine a brand in the eyes of consumers, but it can also be damaging to relationships with HDR content owners.
SDR to HDR conversion technology can fix it
While the industry continues to develop HDR, one way to address the current situation is the use of SDR to HDR conversion. It removes many of the roadblocks to delivering HDR services to the consumer, allowing operators to make use of conversion as needed to deliver an all-HDR viewing experience.
By using conversion at a centralized headend and delivery point, operators can ensure that regardless of what content is coming in, they can provide consumers with the right format to view the high-quality content on the HDR TV sets that they have invested in. However, just signal conversion is not enough – you have to understand the color space and address mapping on top.
A process known as inverse tone mapping (ITM) can be used to rebalance the chroma and luma of the SDR content, allowing it to be shown back to back with HDR content, without any need for the HDR TV set to switch between formats.
At NAB Show 2018, we showcased our new SDR to HDR conversion toolset that enables broadcasters to meet the complex requirements of delivering a consistent, high quality HDR live TV service. MediaKind Encoding Live video processing platform, with its unique implementation of SDR to HDR conversion technology, was extremely well received, winning both Streaming Media’s ‘Best of NAB’ award and NewBay Media’s ‘Best of Show’ award.
Getting HDR right is critical
While conversion technology removes the roadblocks to delivering HDR content, service providers still need to concentrate on delivering a high-quality consumer experience. There’s no question that delivered correctly, HDR can provide an exceptionally rich and immersive user experience. However, incorrect algorithms or the wrong tone mapping can degrade the user experience, which will only serve to stall its progress in the market.
While SDR-to-HDR conversion is not just a question of implementing a simple conversion mechanism – it requires the right kind of technical expertise – it is something that can be done now to ensure the industry has much needed forward momentum to progress the continuous evolution of picture quality and the immersive consumer experience.