Wide Color ISDB-TB FTP SET TOP BOX DISPLAY. RGB and YPbPr Color Space ¢â‚¬¢ YPbPr color cube shows Parallel-Piped

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  • Wide Color Gamut SET EXPO 2016

    31 AUGUST 2016

    Eliésio Silva Júnior Reseller Account Manager E/ esilvaj@tek.com T/ +55 11 3530-8940 M/ +55 21 9 7242-4211 tek.com

  • Anatomy Human Vision

    CIE Chart

    Color Gamuts

    Wide Color Gamut

    2

    Gamma and High Dynamic Range

  • http://webvision.med.utah.edu/index.html

    • Eye, Lens and Retina

    ▪ Rods

    ▫ Sensitive to Blue-green light

    ▫ Used for vision under dark-dim conditions.

    ▪ Cones

    ▫ 3 Types of Cones

    Sensitive to either

    long wavelengths of light (red light)

    medium wavelengths of light (green light)

    short wavelengths of light (blue light)

    ◦ Optic nerve

    Basic Anatomy - Human vision system PHYSICAL PART/ELEMENTS

    3

    http://webvision.med.utah.edu/imageswv/3cone.jpeg

  • Color Model – CIE color spaces

    4

    BT709/sRGB (70% NTSC) ~SMPTE C

    BT2020

    CIE-1931 chart

    D65 white

    NTSC (1953)

    • CIE 1931 XYZ color space

    ◦ Still foundation of most color models

    • Trichromatic stimulus (color value)

    • Lightness decreases towards not shown third dimmension

    • Saturation increases towards edges

    CIE-1976 chart (More perceptually uniform than CIE-1931)

    D65 white

    BT2020

    BT709/sRGB ~SMPTE C

    NTSC (1953)

    Black

    White

  • ITU 601-7 & 709-5 Chromaticity

    601-7 525 CIE x CIE y

    Red 0.630 0.340

    Green 0.310 0.595

    Blue 0.155 0.070

    White 0.3127 0.3290

    5

    709-5/601 625 CIE x CIE y

    Red 0.640 0.330

    Green 0.300 0.600

    Blue 0.150 0.060

    White 0.3127 0.3290

    ITU-R BT 709-5

    ITU-R BT 601-7

    31 AUGUST 2016

  • Wider Color - Chromaticity

    6

    CIE x CIE y

    Red 0.708 0.292

    Green 0.170 0.797

    Blue 0.131 0.046

    White 0.31272 0.32903

    ITU-R BT 2020

    709-5 CIE x CIE y

    Red 0.640 0.330

    Green 0.300 0.600

    Blue 0.150 0.060

    White 0.3127 0.3290

    ITU-R BT 709-5

    31 AUGUST 2016

  • Wider Color - Chromaticity

    7

    CIE x CIE y

    Red 0.73470 0.26530

    Green 0.14000 0.86000

    Blue 0.10000 -0.02985

    White 0.31272 0.32903

    CIE x CIE y

    Red 0.680 0.3230

    Green 0.2650 0.6900

    Blue 0.150 0.06000

    DCI P3 D65 0.3127 0.3290

    SMPTE 2048-1 Free Scale (FS) Gamut

    X’Y’Z’ Color Space EG431-2 (P3)

    31 AUGUST 2016

  • ACES Color Space - Academy Color Encoding System

    8

    CIE x CIE y

    Red 0.73470 0.26530

    Green 0.00000 1.00000

    Blue 0.00010 -0.07700

    31 AUGUST 2016

    Color image encoding system created

    by the Academy of Motion Picture Arts

    and Sciences that allows for a fully

    encompassing color accurate workflow.

  • Wide(er) Color Gamut Percentage

    BT709/sRGB (70% NTSC) ~SMPTE C

    BT2020

    CIE-1931 chart

    D65 white

    NTSC (1953)

     NTSC occupies 47.3% of CIE Chart 1931

     709 occupies 33.5% of CIE chart 1931

     DCI-P3 occupies 44.5% of CIE Chart 1931

     2020 occupies 63.3% of CIE Chart 1931

    9

  • Wide(er) Color Gamut

    10

  • Wide(er) Color Gamut Video Ecosystem

    11

    Baseband Video

    MPEG Signal

    Transport Stream

    • File- Based Video

    QAM

    Optical

    DVB

    ISDB-TB

    FTP

    SET TOP BOX

    DISPLAY

  • RGB and YPbPr Color Space

    • YPbPr color cube shows Parallel-Piped of RGB colors

    • Certain YPbPr values when converted to RGB will fall outside the

    allowed range and will be out of Gamut

    12

  • 525 RGB to SD (601) & HD (709) YPbPr

    13

    100% Color Bars SD 525 RGB

    SD 525 YPbPr HD 1080 YPbPr

  • HD/UHD (709) YPbPr and UHD (2020)

    14

    UHD (709) YPbPr

    UHD (2020) YPbPr / 525

    HD 1080 YPbPr

    UHD (709) & (2020) YPbPr

  • 15

    4K Monitoring – ITU-R BT.2020

  • 16

    Gamut

    16

  • 17

    Gamut

    17

  • 18

    Gamut

    18

  • 19

    Gamut

    19

  • 20

    Gamut

    20

  • 21

    Gamut

    21

  • 22

    Gamut

    22

  • 23

    Color Space

    23

  • Why does HDR look better than SDR ?

    • Are HDR screens brighter on average?

    • Are HDR screens darker on average with blacker blacks?

    • Is the average picture level (APL) unchanged?

    31 AUGUST 2016 24

  • Why does HDR look better than SDR

    HDR RETAINS BRIGHT SPECULAR HIGHLIGHTS AS WELL AS

    DETAIL IN BLACKS

    WHICH CAN MAKE COLORS APPEAR MORE SATURATED.

    Sky Light: >500K nits Looking at the sun > 1 billion nits (don’t look at it)

    Lap top or TV: 100 to 200 nits (hard to see in bright daylight

    Shadows: .1 to 10 nits With day adapted eye shadows can be 10 nits. In living room, less than 0.1 nits

    25

  • Total Visual Dynamic Range

    26

    HDR MAPPING INTO CAMERA F-STOPS (0 STOP = 18% REFLECTANCE)

    Nits (cd/m^2)

    M eso

    p ic

    P h

    o to

    p ic

    Sco to

    p ic

    ST.2 0

    8 4

    H D

    R D

    isp lay

    So n

    y, A R

    R I, C

    an o

    n ~1

    6 -sto

    p s

    P u

    sh

    P u

    ll

    10^8

    10^-6

    10^6

    10^4

    10^2

    10^0

    10^-2

    10^-4

    (18%) 20

    starlight

    moonlight

    indoor lighting

    Sun light outdoor 24

    -sto p

    s w ith

    so m

    e ad

    ap tio

    n

    A d

    ap te

    d Eye

    B ri

    gh t

    ad ap

    ti o

    n

    D ark A

    d ap

    tio n

    7 -sto

    p s

    Sunlight outdoor

    Indoor Lighting

    Moonlight

    Starlight

    (5000 nits)8

    (.08 nits) -8

    6

    4

    2

    -2

    -4

    (20nits) 0

    -6

    Stops

    A d

    ap te

    d Eye

    ~7 -sto

    p s

    B ri

    gh t

    ad ap

    ti o

    n

    D ark

    ad ap

    tio n

    (100nits)2.5

    (18%)

    (90%)

  • Potential Issues with Bright HDR displays

    27

    • Color shift in the Mesopic-level adaption (dark viewing environment) • As light moves below Photopic (dominated by cones) and gets closer to Scotopic (dominated by rods) color

    saturation will diminish. • This may occur in dark scenes in low-light home theater.

    • Light/Dark Adaption (bleaching process rather than pupil size) • Sustained bright images cause the photo-pigment in the retina to reduce and can result in the perception

    of after images. • Dark adaption can take seconds or even minutes. Changes to dark scenes from bright scenes may take

    more time in dark theater as opposed to same scene in higher ambient light.

    • Viewing distance • Static adaption is only about 7 to 9 stops. • To take full advantage of HDR (> 9 stops) via local adaption, you have to be closer than 2 screen widths • If you do sit this close, you may get eye strain

    • Large Area Flicker • Strobing of high peak light levels may cause distress to some viewers. Perceptual flicker frequency may be

    increased since it is a function of retinal adaption. May contribute to PSE (BT.1702). • Frame rate judder may be more visible.

  • Proposed HDR Formats

    • SMPTE ST.2084:2014 High Dynamic Range Electro-Optical Transfer Function of Mastering

    Reference Displays

    “Dolby Vision”

    Perceptual Quantizer (PQ) based on Barten contour perception

    EOTF is inverse of OETF allowing .001 to 10K nits with 10-bits

    Current “Pulsar” display peaks at about 4K nits

    • Hybrid Log-Gamma, “HLG”, from BBC/NHK (ARIB STD-B67)

    Extends log processing (de-facto in many cameras) of high brightness peaks to mitigate blown-out or clipped whites

    Seamless “gamma” power-law processing in blacks as in BT.709/BT.2020 but without linear segment

    Displays can evolve to allow 400X to 800X increase in display

    Allows display EOTF to adjust system gamma to correct for surround illumination (i.e. 10 nits to 500 nits)

    2831 AUGUST 2016

  • Proposed HDR Formats

    • Philips Parameter-based from HDR master

    Embed low bit-rate HDR and SDR conversion parameters into metadata

    Extract parameters during decode and tune display for peak luma

    Optional Y’u’v’ encoding (more perceptually uniform)

    • Technicolor Video Mastering and Distribution Workflow

    Grade both an HDR and SDR master

    Vital to maintain “Artistic Intent”

    • Academy Color Encoding System (ACES)

    (dynamic range and wide color gamut preserving workflow, not an HDR format)

    33 bit floating point

    10-bit proxy