LARA G. CUNNINGHAM

LIFE IN 4K

WITH 4K CONTENT BECOMING INCREASINGLY COMMON, SEVEN PRODUCTION REGIONAL DIRECTOR, LARA GHANEM-CUNNINGHAM, SETS OUT THE MOST IMPORTANT FACTORS THAT MUST BE CONSIDERED WHEN STREAMING IN 4K.

As the world becomes more connected through technology, viewers expect high-quality, live access to everything from news and sporting events, to concerts and ceremonies. With 4K UHD TVs now making up the majority of large screen sales worldwide and 4K broadcasting quickly becoming the norm, broadcasters are facing increased pressure to differentiate and deliver engaging live content for UHD screens.

This task becomes even more complex when streaming 4K video at low latency over IP networks – especially over the internet. However, if done correctly, it presents the possibility for broadcasters to introduce live 4K services while lowering production costs. “Advances in video encoding, especially HEVC, make it possible to stream 4K UHD content over a standard internet connection,” began Seven Production Regional Director, Lara Ghanem-Cunningham. “HEVC can reduce the size of video streams by up to 50% compared to H.264 [also known as AVC],” she added. “When broadcasters use HEVC video encoding for remote production workflows, they can keep bandwidths low while sustaining quality levels of streaming for live television production, in both HD and 4K.”

Latency is an all-too-common problem for live broadcast production. “Too much latency during the start of broadcast contribution will result in higher latency further down the workflow,” Ghanem-Cunningham explained. “Similarly, with HD content, broadcast engineers and remote production managers need to guarantee that 4K video encoding latency levels are under half a second or less.”

To combat this, Ghanem-Cunningham recommends cameras that support high frame rate recording, such as the Sony FS5 and Panasonic AW-UE100 4K. “Ideal for 4K and HD streaming, the Sony FS5 offers High Frame Rate (HFR) cache recording at Full HD 10-bit 4:2:2 image quality and a frame rate of up to 240fps. Higher frame rates of 480fps and 960fps are also possible at specific resolutions, which allow for the highest quality of live images, reducing latency,” she noted.

“Additionally, Panasonic’s AW-UE100 4K Robotic Camera is designed to support highbandwidth NDI for low-latency transmission of high-quality 4K 60p video, and SRT for high-quality and stable transmission. It is also compatible with 12G-SDI output for use in a wide range of situations, to include live streaming events.” While eight-bit colour may work for standard HD content streaming, 4K UHD requires 10-bit colour to support wider colour spaces and HDR. “If you wish to provide your viewers with the best viewing experience, you need to include the option of switching between eight or 10-bit pixel depths, as 10-bit colour over internet workflows can provide enhanced viewing for both HD and 4K,” she explained, recommending Sony’s PMW-F55 camera, which “produces thrilling cinematic images, thanks to the full-size 35mm CMOS sensor that renders every scene with extraordinary colour, contrast, and ultra-low noise even in challenging low-light conditions”.

Although 3G SDI connectors are more than capable of capturing live HD video from HD cameras, for an enhanced broadcast experience, four 3G SDI connectors or a 12G SDI input is required. “The EVS XT4K Production Server provides the optimal 12G SDI connection. With four 4K connectors, it handles all 4K replay requirements in an ultra-reliable, ultra-fast workflow, from ingest to playout.”

Finally, Ghanem-Cunningham noted that the foundation of 4K content is all about delivering a great viewer experience. “When 4K stream quality is affected by unreliable internet links, the viewing experience is compromised,” she said. “It’s important to reliably stream 4K content using a secure transport protocol when streaming over the internet. Using SRT to encrypt video in the AES-128 and 256-bit standard also ensures valuable content is kept away from prying eyes.” Photo: Seven Production www.7production.net