Figure 1 - uploaded by Mike Nilsson
Content may be subject to copyright.
The resolution of UHD relative to earlier, lower, resolutions.

The resolution of UHD relative to earlier, lower, resolutions.

Source publication
Technical Report
Full-text available
This is a research paper commissioned and published by BT Wholesale in April 2015, describing the Ultra High Definition Video aspects of increased resolution, higher dynamic range, wider colour gamut and increased frame rate, as well as providing an overview of the state of standardisation at the time.

Contexts in source publication

Context 1
... resolutions are frequently referred to as either 4K or Ultra High Definition TV (UHDTV) and have resolution 3840x2160, that is, four times the resolution of full High Definition TV. Figure 1 shows the resolution of UHD relative to the earlier formats of Standard Definition (SD), HD-ready (720p HD), and High Definition (HD). UHD televisions are now retailing in significant numbers 1 , enabling potentially much better picture quality than current HD televisions. ...
Context 2
... results are shown in Figure 10, with the experimental results labelled as 'HVS Small Patch' and 'HVS Larger Patch'. It can be seen that as the ambient illumination is increased, the lowest level of black that can be distinguished from absolute black increases. ...
Context 3
... shown in Figure 10 is the black level of a black diffuse surface with reflectance of 3%, such as black velvet, and the performance of three displays: a CRT with minimum light emission of 1cd/m 2 and 3% reflectance; a conventional CCFL (cold cathode fluorescent lamp) backlight LCD with minimum light emission of 0.8cd/m 2 and 1% reflectance; and a modern LED-backlight LCD with spatially uniform back-light dimming with minimum light emission of 000163cd/m 2 and 1% reflectance.1.3/2.4 ...
Context 4
... CRT appears grey compared to the diffuse black (velvet) for ambient light below 300lux (about 2.5 on the horizontal axis of Figure 10), a level of brightness found in an office or a very well lit room in a home 21 . For the CCFL-LCD, this threshold is 100lux (2.0 in Figure 10), typical of a room in a home. ...
Context 5
... CRT appears grey compared to the diffuse black (velvet) for ambient light below 300lux (about 2.5 on the horizontal axis of Figure 10), a level of brightness found in an office or a very well lit room in a home 21 . For the CCFL-LCD, this threshold is 100lux (2.0 in Figure 10), typical of a room in a home. This is because the display effective black level is higher than the luminance of a diffuse black surface, due to a combination of reflectance and the minimum light emissions of the displays. ...
Context 6
... experimental results indicate that the eye can appreciate even deeper black than a diffuse black surface, and that of the considered display technologies, only the LED-LCD display can satisfy the demands of the human visual system, and only at levels below about 1.6lux (0.2 in Figure 10, where the LED-LCD curve crosses the HVS Larger Patch curve), an indoor illumination level that could be considered near pitch black. The problem is not the minimum light emissions which are very low, but the reflectance of ambient light from the screen. ...
Context 7
... example of the actual result of their tone mapping, and how it differs for different ambient light conditions, is shown in Figure 12. 23 Kunkel and Daly 24 stated that current displays are very thin and highly reflective perpendicular to the display: they are similar to mirrors! ...
Context 8
... Intra frames were extracted from the recorded video and tested with software from IMATEST. The results are reproduced in Figure 13. ...
Context 9
... can be seen that the Arri and Sony cameras produced a usable dynamic range of about 14 stops, and the Canon cameras about 11-12 stops. Figure 13 also shows that these cameras use a variety of transfer functions to map linear light to digital code values. ...
Context 10
... colour matching functions are the amounts of primaries needed to match the monochromatic test colour. These colour matching functions, known as the "1931 CIE standard observer", are shown in Figure 14. The wavelengths at which one of the colour matching functions goes negative correspond to the test cases where a variable amount of one of the primaries was added to the test colour, and a match with the remaining two primaries was carried out: the test colour is effectively being matched by a positive contribution from two primaries and a negative contribution from the other. ...
Context 11
... results in the CIE rg chromaticity space as shown in Figure 15. The curve shown represents the colours of single wavelength. ...
Context 12
... CIE 1931 xy chromaticity diagram, taken from Wikipedia 40 , is shown in Figure 16, together with the RGB primaries: 700nm (red), 546.1nm (green) and 435.8nm (blue). All colours within this triangle defined by the three primaries can be made by mixing the three primaries in the appropriate non-zero combination. ...
Context 13
... both cases of CRT and LCD displays, the colour primaries are not single wavelength sources, but have quite spread spectra, as shown in Figure 17, where the CRT image is from Wikipedia 41 and the right image is recreated from Chen at al 42 . ...
Context 14
... ITU-R Recommendation BT.709, and the earlier BT.601, defined a set of colour primaries, in terms of the CIE 1931 x and y chromaticity diagram, to be used in television systems. These colour primaries, and the colour space defined by them, are shown in the CIE 1931 xy chromaticity diagram of Figure 18, taken from Wikipedia 43 . ...
Context 15
... system is still in use today, although as described fully below, there is significant interest in extending display specifications and consequently producing devices to support wider colour spaces. It can be seen clearly in Figure 18 that this colour space leaves a large set of colours that could not be displayed. Care should be taken when quantifying this, because, as pointed out above, CIE 1931 is not a perceptually uniform colour space. ...
Context 16
... stated above, Figure 18 shows the primary colours of the BT.709 colour space. These are joined to form a triangle, which is often referred to as the bounds of the colour space. ...
Context 17
... in order to describe the full range of colours that can be represented in a colour space, for example that described in BT.709, it is necessary to consider a 3D colour volume. Assuming this 3D colour volume to be drawn with the x and y chromaticity coordinates in the horizontal plane, and the luminance, Y, vertically, then the horizontal cross section of the 3D colour volume is the triangle shown on Figure 18 up to a relative luminance of 0.0722, at which point the blue primary cannot add to the relative luminance. In order to increase relative luminance of blue beyond this level, it is necessary to desaturate it by adding red or green or a mixture of the two. ...
Context 18
... This is shown on the CIE 1931 xy chromaticity diagram in Figure 19 ...
Context 19
... illustrates the need for both a wider colour gamut and a higher dynamic range, as stated by Kunkel and Daly 24 , who quote an example of a volcano at night, such as that illustrated in . Emissive colour, such as the molten lava of Figure 21, can be both very bright and very saturated, and outside of the 3D colour volume, as shown on Figure 20. ...

Citations

... Video resolutions are continuously increasing to provide more realistic and immersive experiences. Following the success of High Definition (HD) video services, the Ultra High Definition (UHD) format [20] is now a reality and is considered the future standard for video applications. Popular video streaming platforms such as YouTube, Netflix, or Amazon already support 4K UHD resolution videos. ...
Article
Full-text available
No-Reference video quality assessment has become a trending and challenging hot topic in estimating perceived quality in audiovisual content. In this paper, we present a proposal to considerably reduce the computational cost of video processing without losing accuracy in QoE estimation. Tests have been performed using the Video-MOS SaaS solution, a hybrid NR-VQA solution based on perceptible video distortions and a machine learning approach. After exploring the spatial and temporal redundancy present in a video sequence, the final approach combines video metric feature extraction in both high and low video resolution, together with a specific frame selection based on a uniform temporal sampling and frame type at the video coding level. An extensive validation with more than 144 hours of audiovisual content from six of the most important HD channels of DTT in Spain demonstrates the validity of the approach, ensuring real-time application on the test device, with computational cost savings of 94.96% and an obtained MOS error of 0.1144, in more than 174000 3-second measurements.
... T HE DEPLOYMENT of the latest Ultra-High Definition TV (UHDTV) system [1] aims to increase the user's Quality of Experience (QoE) by introducing to the existing High Definition TV (HDTV) system [2] new features such as higher spatial resolution, High Dynamic Range (HDR), wider color gamut and High Frame-Rate (HFR) [3], [4]. Technical definition of the UHDTV signal is available in the BT. ...
... Along with a wider color gamut and an increased bitdepth, which allow to depict real colors and avoid ringing artifacts respectively, the key features of the UHDTV signal enabling a better depiction of live content are the higher spatial resolution -up to 3840x2160 and 7680x4320 pixels -and increased frame-rate -up to 120 fps. The different experiments that lead to the definition of each characteristic of the UHDTV signal are summarized in [3], [19]. ...
Article
Full-text available
The Digital Video Broadcasting (DVB) has proposed to introduce the Ultra-High Definition services in three phases: UHD-1 phase 1, UHD-1 phase 2 and UHD-2. The UHD-1 phase 2 specification includes several new features such as High Dynamic Range (HDR) and High Frame-Rate (HFR). It has been shown in several studies that HFR (+100 fps) enhances the perceptual quality and that this quality enhancement is content-dependent. On the other hand, HFR brings several challenges to the transmission chain including codec complexity increase and bit-rate overhead, which may delay or even prevent its deployment in the broadcast echo-system. In this paper, we propose a Variable Frame Rate (VFR) solution to determine the minimum (critical) frame-rate that preserves the perceived video quality of HFR video. The frame-rate determination is modeled as a 3-class classification problem which consists in dynamically and locally selecting one frame-rate among three: 30, 60 and 120 frames per second. Two random forests classifiers are trained with a ground truth carefully built by experts for this purpose. The subjective results conducted on ten HFR video contents, not included in the training set, clearly show the efficiency of the proposed solution enabling to locally determine the lowest possible frame-rate while preserving the quality of the HFR content. Moreover, our VFR solution enables significant bit-rate savings and complexity reductions at both encoder and decoder sides.
... Given the widespread uses of computers, tablets and mobile phones [18], these increasingly bright screens, such as those with a peak luminance of 1000 cd/m 2 [19], likely also play an important role in influencing occupants' circadian rhythms. Sivaji et al. investigated office workers' task performance using a computer under three lighting conditions: 2700 K, 4000 K and 6200 K [20]. ...
Article
Full-text available
Light that enters humans’ eyes and impacts circadian rhythms may come from various sources, including the sun, electric lighting systems, and self-luminous displays. Occupants’ activities strongly impact the light entering their eyes, which is difficult to predict and not yet well understood. This study investigated the circadian contributions of light from different sources in real building environments to better understand the variables that influence the circadian health of occupants. Spectral irradiance distributions at a position equivalent to the front of an eye of a seated occupant in various interior office spaces were collected. Daylight and electric light were measured separately, and light emitted from displays was measured when a variety of different computer tasks was performed. Circadian stimulus (CS) and α-opic irradiance, defined by CIE DIS026/E:2018, were further calculated, and the circadian effects of light from different sources were compared. The results show that daylight has the greatest circadian effect, while electric light in spaces that were predominantly designed with conventional downward lighting has a very limited impact. The circadian effect of light from screens was considerably high. The outcomes suggest that, to optimise the circadian effects of light, connected lighting systems are needed to control light from different sources.
... The decoding stage contains all the decoders that are used to convert the input video signals to a digitally formatted form suitable for digital processing. As shown in Fig. 4 takes an input video signal V i with a standard such as NTSC, PAL, SECAM, DVI or HDMI, and produces an appropriate n-bits digitally formatted videoV i in a standard protocol such as BT.656, BT.709, BT.2020 [18], along with a synchronization clock c i (t). The control module shown in Fig. 4 configures each video decoder according to the standard of the input video and the required digital format of the converted output video through an interface such as serial bus protocol, e.g., inter-integrated circuit I 2 C or serial peripheral interface SPI standards. ...
Article
Full-text available
Simultaneous processing of multiple multimedia appears in many applications. However, there is a lack of a generalized hardware platform that fits all application needs from the number to the format of the input and output multimedia. The processing is also associated with synchronization problems such as startup delays and deviating frame rates of the multimedia. This paper presents a flexible platform with co-design of hardware and software for the applications specific needs. On the hardware side, it presents modular and scalable architecture that considers: the required number of input and output multimedia signals, the mixed analog and digital multimedia signals and their processing hardware components crosstalk to minimize the signal-to-noise ratio on the platform, and finally the low power consumption. On the processing side, a synchronization module is proposed and efficiently implemented to handle the startup delays and the deviating frame rates of the input multimedia signals. The system hardware and software were implemented for two case studies. A case study for fusion of multimedia signals of different modalities (visible and near infra-red (RGBN)), that is needed for modern smart phone cameras, is presented. Another case study for producing a 4K format required for larger displays is included, that stitches 9 high-definition videos simultaneously. The multimedia pipeline: decoding, processing, encoding were all realized and implemented successfully. The system performed in real-time of 30 frames per second. The platform end-to-end signal-to-noise ratio where above 56 and reaching 102 decibels, and the power consumption was below 2 Watts, making it suitable for real-time embedded multimedia systems.
... The deployment of the latest Ultra High Definition TV (UHDTV) [1] systems aims to increase the user's Quality of Experience (QoE) by introducing to the existing High Definition TV (HDTV) system [2] new features such as higher spatial resolution, High Dynamic Range (HDR), wider color gamut and High Frame-Rate (HFR) [3,4]. The introduction of these new features is driven by the will to provide a more realistic and immersive experience to the consumer. ...
Conference Paper
Full-text available
A two-layer low-complexity scalable encoding scheme based on local Adaptive Spatial Resolution (ASR) is proposed. This scheme relies on a block-level spatial resolution adaptation in the enhancement layer encoder. For each block, the optimal resolution is either obtained via a rate-distortion optimization followed by a decision refinement process or by a prediction via motion compensation exploiting the base layer motion vectors. The proposed architecture has been integrated over of the High Efficiency Video Coding (HEVC) reference software (HM16.12) which is used as a base layer encoder. Compared to SHVC, the scalable extension of HEVC, experimental results show bitrate savings of 0.76 % as well as encoding complexity reductions of 47 % for the whole scalable encoder and 96 % for the enhancement layer encoder.
... Although standard cinema specifications only require a luminance of 48 cd/m 2 [DCI 2012], high dynamic range and ultra-bright displays are becoming ever more common and important as part of UHD television [Nilsson 2015]. Major TV manufacturers including LG, Sony, Panasonic, Samsung and TCL have released consumer-level HDR screens with peak luminance varying from 800-4000 cd/m 2 , with yet brighter displays announced or demonstrated. ...
Article
The perceived discrepancy between continuous motion as seen in nature and frame-by-frame exhibition on a display, sometimes termed judder, is an integral part of video presentation. Over time, content creators have developed a set of rules and guidelines for maintaining a desirable cinematic look under the restrictions placed by display technology without incurring prohibitive judder. With the advent of novel displays capable of high brightness, contrast, and frame rates, these guidelines are no longer sufficient to present audiences with a uniform viewing experience. In this work, we analyze the main factors for perceptual motion artifacts in digital presentation and gather psychophysical data to generate a model of judder perception. Our model enables applications like matching perceived motion artifacts to a traditionally desirable level and maintain a cinematic motion look.
... The brightness and contrast of display devices have improved in recent years and are expected to further improve in the future. Currently, many consumer displays can achieve a peak luminance of 2 500 cd m and some high-end displays available in the market are able to reach a peak luminance of above 2 1000 cd m [1]. The achievable luminance range is expected to further increase in the near future. ...
... Dolby's highlight study also suggested that the upper level of the luminance range should at least be 2 10, 000 cd m for preferred highlight reproduction [2]. The International Telecommunication Union (ITU) has recommended BT.2020 (or Rec.2020) primaries for the next generation ultrahigh definition (UHD) broadcasting system and its format [1]. The Rec.2020 gamut is wider than display color encodings such as ITU-R BT.709, sRGB, Adobe RGB, or DCI-P3, and covers 99.9% of the Pointer gamut (naturally occurring colors) [1,3]. ...
... The International Telecommunication Union (ITU) has recommended BT.2020 (or Rec.2020) primaries for the next generation ultrahigh definition (UHD) broadcasting system and its format [1]. The Rec.2020 gamut is wider than display color encodings such as ITU-R BT.709, sRGB, Adobe RGB, or DCI-P3, and covers 99.9% of the Pointer gamut (naturally occurring colors) [1,3]. A color space is desired that is perceptually uniform in wide gamut such as Rec.2020, can predict wide-range of lightness, and has minimal inter-dependence between its perceptual attributes (lightness, chroma, and hue). ...
Article
Full-text available
A perceptually uniform color space has been long desired for a wide range of imaging applications. Such a color space should be able to represent a color pixel in three unique and independent attributes (lightness, chroma, and hue). Such a space would be perceptually uniform over a wide gamut, linear in iso-hue directions, and can predict both small and large color differences as well as lightness in high dynamic range environments. It would also have minimum computational cost for real time or quasi-real time processing. Presently available color spaces are not able to achieve these goals satisfactorily and comprehensively. In this study, a uniform color space is proposed and its performance in predicting a wide range of experimental data is presented in comparison with the other state of the art color spaces.
... The brightness and contrast of display devices have improved in recent years and are expected to further improve in the future. Currently, many consumer displays can achieve a peak luminance of 2 500 cd m and some high-end displays available in the market are able to reach a peak luminance of above 2 1000 cd m [1]. The achievable luminance range is expected to further increase in the near future. ...
... Dolby's highlight study also suggested that the upper level of the luminance range should at least be 2 10, 000 cd m for preferred highlight reproduction [2]. The International Telecommunication Union (ITU) has recommended BT.2020 (or Rec.2020) primaries for the next generation ultrahigh definition (UHD) broadcasting system and its format [1]. The Rec.2020 gamut is wider than display color encodings such as ITU-R BT.709, sRGB, Adobe RGB, or DCI-P3, and covers 99.9% of the Pointer gamut (naturally occurring colors) [1,3]. ...
... The International Telecommunication Union (ITU) has recommended BT.2020 (or Rec.2020) primaries for the next generation ultrahigh definition (UHD) broadcasting system and its format [1]. The Rec.2020 gamut is wider than display color encodings such as ITU-R BT.709, sRGB, Adobe RGB, or DCI-P3, and covers 99.9% of the Pointer gamut (naturally occurring colors) [1,3]. A color space is desired that is perceptually uniform in wide gamut such as Rec.2020, can predict wide-range of lightness, and has minimal inter-dependence between its perceptual attributes (lightness, chroma, and hue). ...
Conference Paper
The television and cinema industry has grown very rapidly during last few years and future displays will likely be able to cover high dynamic range (HDR) and wide color gamut (WCG). A uniform color space is desired that is suitable not only for efficient quantization but also for color volume mapping in HDR and WCG environment. A design goal for the next generation display is Rec.2020 which is the minimum requirement for future video encoding. There are a number of aspects which must be considered while developing a color space in order to meet the requirements of future imagery. Current study lists eight different criterions to test the ability of a color space to meet these requirements. After defining the testing criteria, this study investigated four different color spaces including CIELAB, CAM16-UCS, ICaCb, and recently proposed zICaCb. Results showed that zICaCb outperformed other spaces tested for most of the measures and gave similar performance for others.
... The brightness and contrast of display devices have improved in recent years and are expected to further improve in the future. Currently, many consumer displays can achieve a peak luminance of 2 500 cd m and some high-end displays available in the market are able to reach a peak luminance of above 2 1000 cd m [1]. The achievable luminance range is expected to further increase in the near future. ...
... Dolby's highlight study also suggested that the upper level of the luminance range should at least be 2 10, 000 cd m for preferred highlight reproduction [2]. The International Telecommunication Union (ITU) has recommended BT.2020 (or Rec.2020) primaries for the next generation ultrahigh definition (UHD) broadcasting system and its format [1]. The Rec.2020 gamut is wider than display color encodings such as ITU-R BT.709, sRGB, Adobe RGB, or DCI-P3, and covers 99.9% of the Pointer gamut (naturally occurring colors) [1,3]. ...
... The International Telecommunication Union (ITU) has recommended BT.2020 (or Rec.2020) primaries for the next generation ultrahigh definition (UHD) broadcasting system and its format [1]. The Rec.2020 gamut is wider than display color encodings such as ITU-R BT.709, sRGB, Adobe RGB, or DCI-P3, and covers 99.9% of the Pointer gamut (naturally occurring colors) [1,3]. A color space is desired that is perceptually uniform in wide gamut such as Rec.2020, can predict wide-range of lightness, and has minimal inter-dependence between its perceptual attributes (lightness, chroma, and hue). ...
Conference Paper
This study investigated that which of the available color spaces performs best in different aspects when encoding high dynamic range and wide gamut color difference signals. Six different color spaces including CIELAB, CIELUV, CAM16-UCS, ICtCp, ICaCb, and zICaCb (current modification of ICaCb), were investigated for their performance in terms of local and global uniformity, hue linearity, encoding of Rec.2020 signals, convergence of iso-hue lines at single point (locus), distance between locus and origin, and computational cost. A new metric was developed for hue linearity test. Comprehensive testing was performed using the most reliable datasets and some modifications were proposed in the recently developed color space named ICaCb. Results showed that the current zICaCb outperformed other spaces tested for most of the measures and gave similar performance for other measures.
... Content distribution through satellite thus may not be suitable for the enormous content at higher resolutions/frame rates. The higher bandwidth capacities could cater for 3D cinematography [33] and lasers as projection light source [34] with even higher rates. ...
Article
Full-text available
Digital technology has transformed the information flow and support infrastructure for numerous application domains, such as cellular communications. Cinematography, traditionally, a film based medium, has embraced digital technology leading to innovative transformations in its work flow. Digital cinema supports transmission of high resolution content enabled by the latest advancements in optical communications and video compression. In this paper we provide a survey of the optical network technologies for supporting this bandwidth intensive traffic class. We also highlight the significance and benefits of the state of the art in optical technologies that support the digital cinema work flow.