Wide Color Gamut

Wide Color GamutSET EXPO 201631 AUGUST 2016Eliésio Silva JúniorReseller Account ManagerE/ esilvaj@tek.comT/ 55 11 3530-8940M/ 55 21 9 7242-4211tek.com

Anatomy Human VisionCIE ChartColor GamutsWide Color GamutGamma and High Dynamic Range2

Basic Anatomy - Human vision systemPHYSICAL PART/ELEMENTS Eye, Lens and Retina Rods Sensitive to Blue-green light Used for vision under dark-dim conditions. Cones 3 Types of ConesSensitive to eitherlong wavelengths of light (red light)medium wavelengths of light (green light)short wavelengths of light (blue light) Optic nervehttp://webvision.med.utah.edu/index.html3

Color Model – CIE color spacesNTSC(1953)BT2020BT709/sRGB SMPTE CD65 whiteBT2020BlackWhiteNTSC(1953)BT709/sRGB(70% NTSC) SMPTE CD65 whiteCIE-1931 chartCIE-1976 chart(More perceptually uniform than CIE-1931) 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 edges4

ITU 601-7 & 709-5 ChromaticityITU-R BT 601-7601-7 525CIE xCIE 31270.3290ITU-R BT 709-531 AUGUST 2016709-5/601 625CIE xCIE 31270.32905

Wider Color - ChromaticityITU-R BT 2020CIE xCIE 312720.32903ITU-R BT 709-531 AUGUST 2016709-5CIE xCIE 31270.32906

Wider Color - ChromaticitySMPTE 2048-1 Free Scale (FS) GamutCIE xCIE .02985White0.312720.32903X’Y’Z’ Color Space EG431-2 (P3)31 AUGUST 2016CIE xCIE I P3 D650.31270.32907

ACES Color Space - Academy ColorEncoding SystemCIE xCIE .07700Color image encoding system createdby the Academy of Motion Picture Artsand Sciences that allows for a fullyencompassing color accurate workflow.31 AUGUST 20168

Wide(er) Color Gamut PercentageBT2020NTSC(1953)BT709/sRGB(70% NTSC) SMPTE CD65 white NTSC occupies 47.3% of CIE Chart 1931 709 occupies 33.5% of CIE chart 1931CIE-1931 chart DCI-P3 occupies 44.5% of CIE Chart 1931 2020 occupies 63.3% of CIE Chart 19319

Wide(er) Color Gamut10

Wide(er) Color GamutVideo EcosystemTransportStreamBasebandVideoMPEGSignal FileBasedVideoQAMOpticalDVBISDB-TBSET TOPBOXDISPLAYFTP11

RGB and YPbPr Color Space YPbPr color cube shows Parallel-Piped of RGB colors Certain YPbPr values when converted to RGB will fall outside theallowed range and will be out of Gamut12

525 RGB to SD (601) & HD (709) YPbPr100% Color BarsSD 525 RGBSD 525 YPbPrHD 1080 YPbPr13

HD/UHD (709) YPbPr and UHD (2020)HD 1080 YPbPrUHD (709) YPbPrUHD (2020) YPbPr / 525UHD (709) & (2020) YPbPr14

4K Monitoring – ITU-R BT.202015

Gamut1616

Gamut1717

Gamut1818

Gamut1919

Gamut2020

Gamut2121

Gamut2222

Color Space2323

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 201624

Why does HDR look better than SDRHDR RETAINS BRIGHT SPECULAR HIGHLIGHTS AS WELL ASDETAIL IN BLACKSWHICH CAN MAKE COLORS APPEAR MORE SATURATED.Sky Light: 500K nitsLooking at the sun 1 billion nits(don’t look at it)Lap top or TV: 100 to 200 nits(hard to see in bright daylightShadows: .1 to 10 nitsWith day adapted eye shadowscan be 10 nits. In living room,less than 0.1 nits25

Total Visual Dynamic Range10 6610 410 -210 -410 -6Nits (cd/m 2)Pull(18%)-2DarkadaptionStarlight(20nits) 0-4PushstarlightDark AdaptionmoonlightMesopic ScotopicMoonlight(100nits)2.5(90%)2Adapted Eye 7-stops10 0Sony, ARRI, Canon 16-stops(18%) 2047-stopsindoorlightingAdapted Eye10 2ST.2084 HDR DisplayIndoorLightingPhotopicSun lightoutdoorBright adaption(5000 nits)824-stops with some adaptionSunlightoutdoor10 8BrightadaptionHDR MAPPING INTO CAMERA F-STOPS (0 STOP 18%REFLECTANCE)-6(.08 nits) -8Stops26

Potential Issues with Bright HDRdisplays 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) colorsaturation 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 perceptionof after images. Dark adaption can take seconds or even minutes. Changes to dark scenes from bright scenes may takemore 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 beincreased since it is a function of retinal adaption. May contribute to PSE (BT.1702). Frame rate judder may be more visible.27

Proposed HDR Formats SMPTE ST.2084:2014 High Dynamic Range Electro-Optical Transfer Function of MasteringReference Displays“Dolby Vision”Perceptual Quantizer (PQ) based on Barten contour perceptionEOTF is inverse of OETF allowing .001 to 10K nits with 10-bitsCurrent “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 whitesSeamless “gamma” power-law processing in blacks as in BT.709/BT.2020 but without linear segmentDisplays can evolve to allow 400X to 800X increase in displayAllows display EOTF to adjust system gamma to correct for surround illumination (i.e. 10 nits to 500 nits)31 AUGUST 201628

Proposed HDR Formats Philips Parameter-based from HDR masterEmbed low bit-rate HDR and SDR conversion parameters into metadataExtract parameters during decode and tune display for peak lumaOptional Y’u’v’ encoding (more perceptually uniform) Technicolor Video Mastering and Distribution WorkflowGrade both an HDR and SDR masterVital to maintain “Artistic Intent” Academy Color Encoding System (ACES)(dynamic range and wide color gamut preserving workflow, not an HDR format)33 bit floating point10-bit proxy output in stops (log2).31 AUGUST 201629

Capturing a Camera RAW imageGamma0% Black10-bit Code-Value%18% Grey(20 nits illumination)10-bit Code-Value%90% Reflectance%10-bit Code-ValueS Log 190339437.763665S Log 290334732.358259S Log 335132.861463ACES (proxy)NDND42641.352455BT.70964042341.094010031 AUGUST 201630

Camera (scene) referenced 709 to PQLUT conversionCamera-Side ConversionBT.709 toconversionPQCamera-sideBT . 709 to P Q1002084 HDR0%2%18 %90%100%709100nits094195100HDR 1000nits03758HDR 5000nits003124514294180SDR BT.709,100,100070SDR BT.709,100,200060SDR BT.709,100,5000SD R 2HDBTR CS,100,10007576709iSD R 2 HDBTR CS709,100,2000iHDR 2000nits906868SD R 2 HDBTR .709i IRE% or I RESDR and HDR displays DO NOT match.Blacks are stretched in the BT1886 Display but not the PQ Display (matches scene)31 AUGUST 201631

Studio Monitor referenced 709 to PQLUT conversionDisplay-Side ConversionBT.709to PQDisplay-side conversionBT.709 to PQ10 02084 HDR709100nitsHDR 1000nitsHDR 2000nitsHDR 5000nits0%2%18 %90%100%094190100000221713524637SDR 2 HDR74 DSBT 7 0759 , 10 0 , 10 00iSDR 2 HDR DSBT 7 0 966SDR 2 HDR DS57i68BT 7 0 958i9904180HDR BT.709,100,100070HDR BT.709,100,200060HDR BT.709,100,5000, 10 0 , 20 0050, 10 0 , 50 00403020100SDR and HDR displays matchBlacks are stretched in both the BT1886 and PQ Display31 AUGUST 201602040608010 0BT 7 0 9BT.709%i IRE% o r IRE32

SMPTE 2084 PQ Look Up TablesLinear Ramp Test SignalBT.70931 AUGUST 2016Look Up TableSMPTE 2084 1000nitsReference White 100nitsLook Up TableSMPTE 2084 1000nitsReference White 300nits33

Slog 2 Camera RAW to HDRHDR 1000 Nits90% Reflectance White 75%,18% Grey 58%31 AUGUST 2016Look Up Table Converted SLog2 to ST 2084 PQNeed HDR Monitor to view this image.34

Slog 2 Camera RAW to HDRHDR 1000 Nits90% Reflectance White 75%,18% Grey 58%31 AUGUST 201635

GammaGamma correction, gamma nonlinearity, gamma encoding, orsimply gamma, is the name of a nonlinear operation used to codeand decode luminance in video or still image systems31 AUGUST 201636

Colour ModelA colour model is an abstract mathematical model describing theway color can be represented as tuples of numbers, typically asthree or four value or color components ( e.g RGB are CMYK arecolor models)31 AUGUST 201637

GamutIn color reproduction, including computer graphics andphotography, the gamut, or color gamut, is a certain completesubset of colors.The most common usage refers to the subset of colors which canbe accurately represented in a given circumstance, such as withina given color space or by a certain output device.31 AUGUST 201638

Colour SpaceColor space is a more specific term for a certain combination of acolor model plus a mapping function, the term “color space” tendsto be used to also identify color models, since identify a colorspace automatically identifies the associated color model.Gamut Colour Model Colour Space31 AUGUST 201639

SummaryGAMMA AND HIGH DYNAMIC RANGE Camera’s today are able to capture a wide dynamic range SDR displays typically clip or blow out the highlights of the image The use of non-linear processing such as S-Log 2, ST 2084 PQand HLG use the bits more efficiently to capture the image Overall this allows HDR displays to utilize the bits more effectively White point and 18% grey levels need to be set correctly using awaveform monitor to simplify the process31 AUGUST 201640

Thank you very muchSee you at booth 33Eliésio Silva JúniorReseller Account ManagerE/ esilvaj@tek.comM/ 55 21 9 7242-4211

Gamut 38 In color reproduction, including computer graphics and photography, the gamut, or color gamut, is a certain complete subset of colors. The most common usage refers to the subset of colors which can be accurately represented in a given circumstance, such as within a given color space or by a certain output device. 31 AUGUST 2016