The Need For Waveform Monitors In 4K/UHD Production

The waveform monitor has always been an essential instrument for anyone working in the video industry and is used everywhere from system design, manufacturing, installation setup, outside broadcast, grading through to quality control, writes Alan Wheable FISTC, MITOL Senior Technical Author at Omnitek.

There is an expectation that T&M equipment caters for all of the possible physical interfaces, video formats, colour spaces and flavours of High Dynamic Range that are just a few of the challenges facing the industry.

With more and more program content being created at 4K with high dynamic range there is a demand for T&M equipment to appropriately support new production work flows.

The importance of appropriate waveform monitor technology in 4K / UHD content creation and distribution increases with the need to ensure that the results of conversions between link types, between encoding methods (such as Square Division and 2 Sample Interleave), between different bit depth formats and between colour spaces are correct.

The waveform monitor does not just have to provide confidence that the picture is present at the correct levels, but must be expandable to pixel level to see any digital artefacts that may have been introduced when converting between 8, 10 and 12-bit video. In addition, image construction issues, for example when converting between link types and encoding methods need to be detected. Having a true full resolution waveform monitor and CIE Chart is essential to allow detection of colour space issues that may otherwise go unnoticed on T&M equipment with small, low resolution displays.

Although some T&M equipment may boast 4K / UHD waveforms, these are often low resolution displays, with sub-sampled waveforms, that give a level of comfort and familiarity, but may not show underlying issues.

For 4K / UHD production, waveform monitors need to be designed specifically to meet the exacting needs of new production workflows while supporting all of the complexities that will be present in the industry for many years to come. Instruments need to be able to analyse down to pixel level, regardless of the physical link over which it is delivered.

At IBC 2016, Omnitek showcased its new Ultra XR, which provides a sophisticated solution for 4K / UHD content monitoring, colour grading and program QC. Ultra XR's picture monitor, true 4K waveform monitor, vectorscope, BT.709 / BT.2020 CIE gamut charts, video timing, audio meters and video / audio status instruments allow SD to 4K analysis as standard in a small form factor unit.

The Ultra XR provides all the traditional tools needed to work with DI – high-resolution waveform display, vectorscope, CIE chart, etc – but engineered specifically with 4K/UHD in mind. The Ultra XR supports 12-bit 4:4:4 SDI input formats in YCbCr and RGB, along with Wide Colour Gamut RGB – ITU-R BT.2020 and High Dynamic Range (HDR) inputs – ST2084 / PQ and Hybrid Log Gamma.

The Ultra XR supports SD, HD, 3G, QL-3G, and 6G-SDI as standard, with 12G-SDI as an option. The ability of the Ultra XR to monitor different physical links as well as Square Division and 2 Sample Interleaved sources ensures that the signal can be viewed and checked regardless of how it actually arrives. This flexibility makes the Ultra XR an ideal fit for existing installations as the technological landscape continuously evolves.

The flexible and intuitive user control and monitoring is provided via HDMI, SDI or web browser connections. The use of mouse & keyboard (optional) allows the control surface to be configured exactly as required and presets can be used to quickly recall previously saved settings.

In addition to the high resolution waveform monitor, traditional instruments such as vectorscope are included. Although this basic tool provides a level of usefulness in 4K / UHD applications, other tools such as CIE Gamut charts (supporting SMPTE C, EBU, BT.709, BT.2020 and DCI colour spaces) are provided to ensure that the colour space rendition of the image is always correct.

All of the waveform instruments can be viewed as tiles or as full screen which is ideal for grading and quality control applications where detail is essential.

To help market their equipment, camera and display screen manufacturers have driven the need for the 'best possible user experience'. One of the challenges that content providers face is being able to deliver this expected 'user experience'. The tools within the Omnitek Ultra XR and 4K Tool Box are available now to help deliver this experience.

www.omnitek.tv

This article is also available to read at BFV online here, page 22.

(JP/LM)