Image by Reuben Klein
4K - A Quick Guide
4K is not a singular format defined by a single set of specifications.
4K’s is made of 4 current sub groups which represent:
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Image size/resolution
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Colour Depth available at given refresh rate
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Colour sub-sampling available at given refresh rate
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Maximum refresh rate
Please refer to the chart at the middle of the page for a full list of 4K formats that are supported via HDMI version 2.0
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4K is a term widely used to describe a very high resolution large size files of video and images. In its simplest form 4K is a resolution that is 4 times larger than 1080p. 4K is also a format that has game-changing features which make it very difficult to describe 4K as a homogenous single specs standard. To better evaluate what 4K is and how many of its features users are able to harness and benefit from, please review the sets of specifications that are described in this document.
4K is describing two sizes:
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3840x2160
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4096x2160
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The 3840x2160 is a format used by home technology devices.
The 4096x2160 is a format used for commercial displays such as movie theatres.​​​​​
​​​Accredited world wide standards
The material will be related to the 3840x2160 4K format.
It is the established home and semi-professional standard that has been chosen during 2015 and 2016 by the following bodies
North America
4K Ultra HD association
https://www.cta.tech/Consumer-Resources/Guides/4K-Ultra-HD.aspx
Europe
Digital Europe
http://www.digitaleurope.org/Services/High-Definition-Logos/UHD
The formats stipulate similar if not identical set of specific standards of luminescence and colour characters which form the very large display.
Definition of 4K and their specifications
The definition and ability of components to produce full Ultra HD (UHD) image are aided by software that are embedded in some of the electronics.
A specific set of a number of features need to be viewed jointly to form the definition of each type of 4K.
Please review the chart below:
​​​Chart courtesy of HDMI LLC
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Refresh Rate
24/25/3050/60 signify the refresh rate of the moving image. It is a measured in Hz. At 60Hz the picture naturality is near identical to that of 35mm film. A frequency of 24Hz will make some games judder and stop.
Colour Depth
The 8/10/12/are colour depth figures, They signify the quantity of colour pigments available to create colours. A 10bit colour depth contains in it 1Billion such pigments. It avails a number of pigments 62,500 times greater than that of 8bit colour depth structure that can only master 16Million such pigments.
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Wide Colour Gamut
The set of figures such as 4:2:0 represent the density of the colour, its intensity if you like, and the number of pigments included in each pixel.
The ability of pixels of various colours and shades to be accurately incorporated in to the constant changing image are denoted with a set of colour pixels orders that signify how intense the colour will be.
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All 8bit transmission is limited to a colour gamut that is defined by the term REC.709. This standard of measuring colour density has existed since the days of CRT displays. 10bit colour depth is able to use a far wider range of colours and colour density elements. It can display 62,500 times more pigments then that displayed by an 8bit 4K displays.
​​​To display the fullest and most complete 4K Ultra HD features, a transmission system requires a minimum of 11.1Gbps (Please see more in the Critical Bandwidth page) Manufacturers of HDbaseT are relaying on clock speeds of 340Mhz per each TMDS channel, the limitation of their equipment does permit the transmission of such signal.
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As demonstrated above, the manner in which 4K is defined can be sometimes opaque.
A review of the upper chart will clearly demonstrate the vast improvements to viewer’s experience that a 10bit image adds.
HDR
HDR technology enhances brightens and colours of the large 3840x2160 resolution images by turning the very sizable image in to a vibrant colourful and highly contrasted image that rival that of professional cinemas. There is a number of HDR standards, it is too early to predict if one of standards will dominate the marketplace. However, HDR10 and Dolby Vision and Hybrid Log Gamma (HLG) should be very closely looked at. Dolby Vision is offering a significant advantage over other HDR implementations as it offers a native 12bit performance. All other HDR techniques rely on a maximum colour depth of 10bits. When combined with a 60Hz the 10bit image will greatly elevate the experience of users as the image is aided by the ability of the HDR feature such as Dolby Vision to transform the viewing experience. The combination of these two will create an image that will rival that of some commercial cinemas.
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NuTec Models outstanding ability is possible as they are all carefully matched and designed to create a complete synergy as a cohesive ecosystem that accurately transmits and portrays the highest quality 10bit image possible. When connected to a 4K source the NueTec systems will transform the experience of end users in their homes.
NeuTec is offering a guaranteed set of performances and will offer measuring devices to verify its guaranteed results.