Why and how to go to Ultra HD phase 2
Maryline CLARE, Orange Labs
Jérôme VIERON, ATEME For Enhanced Video ExpeRience
Summary
• 4EVER-2: description and methods
• UHD-TV phase 2: the real gap in quality of experience
• Focus on HDR – what is HDR
– several technical solutions and standardization committees
– subjective tests
– 4EVER-2 trials
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 2
• HFR: – what it is
– subjective tests
• compressor challenges – HDR
– HFR
• The first UHD-TV phase 2 + NextGen audio production = 4EVER short
• Conclusions, perspectives
What is 4EVER-2?
What do we work on? How?
www.4ever-2.com 3 4EVER-2 : go for UHD-TV phase 2!
4EVER: All about visual quality of TV content
www.4ever-2.com 4
spatial definition (4K)
Quality of Experience?
UHD-TV phase 2
UHD-TV phase 1
Extended colors (Wide Color Gamut, WCG)
Temporal definition (High Frame Rate, HFR)
Contrast definition (High Dynamic Range, HDR)
4EVER-2 : go for UHD-TV phase 2!
4EVER-2 structural keypoints • Consortium and its 9 partners known (4EVER): active contribution to standardization
bodies, TV professional services, …
• Complementary skills over the whole end-to-end audiovisual chain
• Lab research experimented in real premium events (sports, culture)
• Integration of the audio dimension for a real audiovisual quality content evaluation
• Collaboration with worldwide major actors
– Groups and forums : EBU, BBC, IRT, HD Forum
– Consumer and professional equipment manufacturers
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 5
Nine French partners
4EVER-2 : go for UHD-TV phase 2! 6 www.4ever-2.com
Shooting Production Encoding Contribution Distribution
Decoding Playing
Perceived quality
on end-to-end audiovisual chain
4EVER-2: the end-to-end AV chain
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 7
• Orange Labs: coordination, audiovisual assessment tests
• francetélévisions: content production, joined audio visual subjective tests
• AMPVisualTV: live production workflows , UHD-TV equipment evaluation,
• ATEME: HEVC encoding of UHD-TV phase 2 (HDR and/or HFR and/or WCG)
• INSA-IETR: HEVC decoding of UHD-TV phase 2 (OpenHEVC open source)
• HTS: colorimetry science
• Télécom ParisTech: HEVC player (GPAC open source), HDR quality assessement, rendering HDR depending on viewing room conditions
• TeamCast: terrestrial and satellite TV transmission (DVB-T2, DVB-S2X)
• GlobeCast: technical infrastructure for end-to-end content distribution (satellite, IPTV)
1/Experimental shooting sessions • Evaluate production equipments and complete workflow
• Generate ultra high quality sequences with controled parameters
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 8
1/Sequences shared worldwide
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2/Evaluation of video perceived quality
• Display parameters: brightness, contrast
• In the room: light control around the display
• Distance to the screen
• SAMVIQ method (ITU-R BT 1788): adapted to evaluation of video quality on short sequences
• 25 to 20 non expert observers
• SEOVQ software
Subjective tests in standardized environment (REC ITU-R BT.500)
4EVER-2 : go for UHD-TV phase 2! 10 www.4ever-2.com
3/Research and software development
• Colorimetry: science of color
• Research and development
– HEVC encoding • Professional prototypes for encoder: ATEME
– HEVC decoder • Academic research and open source for decoder : INSA-IETR (open HEVC)
– Video player: Télécom ParisTech (GPAC) • Academic research and open source to integrate HEVC decoding and
UHD-TV specificities
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 11
4/Experiment on visible events
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 12
Go on actual premium events to experiment prototype audiovisual end-to-end chain
Stressful, but extremely useful!
5/Disseminate results and conclusions
4EVER-2 : go for UHD-TV phase 2! 13
September 2015
On EBU booth, demonstrating HDR in collaboration with BBC
HFR in collaboration with EBU, BBC, IRT, RAI
www.4ever-2.com
5/Disseminate results and conclusions
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 14
April 2014
UHD-TV in OTT internet HEVC + 4K + DASH + HTML5
for a smooth adaptation of bitrate
(hence quality) to bandwidth variations
UHD-TV for DTT
HEVC + 4K + DVB-T2
5/Disseminate results and conclusions
4EVER-2 : go for UHD-TV phase 2! 15
September 2014
back then, the first and only booth to demonstrate all 4 technologies of
UHD-TV
www.4ever-2.com
5/Disseminate results and conclusions
• Major communication events in 2016
– MIPTV 2016, Cannes France, April
– NAB 2016, selected for Future Labs Park
• Demonstrations : HFR, HDR, ATSC, 4K, HEVC, live, …
• Please visit
– IBC 2016?
• If interesting demonstrations to propose
• If selected for Future Zone…
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 16
Ultra HD-TV phase 2
What for?
www.4ever-2.com 17 4EVER-2 : go for UHD-TV phase 2!
Why a need for WCG, HDR and HFR? 4K not « better enough » in normal TV viewing conditions
www.4ever-2.com 18
but only when sitting at
1,5*height of the display
SD HD UHD
Very good
Good
Fair
Bad
Very Bad
JVC Pro Vérité 84" - Toshiba 55" (1.5H)
55"
84"
SD HD UHD
Very good
Good
Fair
Bad
Very Bad
JVC Pro Vérité 84" - Toshiba 55" (3H)
55"
84"
1,5m
1m
UHD
1m
3m HD
10 points better on a scale of 100
4EVER-2 : go for UHD-TV phase 2!
HFR: always better even at same bitrate
www.4ever-2.com 19
100Hz native contents provide better quality than 50Hz native contents (about 15 points)
4EVER-2 : go for UHD-TV phase 2!
work done in collaboration with
• 100Hz native: much better perceived video
quality than 50Hz native ones
• The performance of Interpolation (MCFI)
depends on the content’s motion features but
in average, 50Hz interpolated at 100Hz
cannot reach the perceived video quality of
native 100Hz
At the same bitrate, the perceived
quality of a 100Hz source remains
better than a 50Hz source
(interpolated or not)
HDR: a real benefit expected Actual improvement potential if conditions are respected
4ever subjective tests results - 2014
www.4ever-2.com 20
Maximum of comfort obtained between 750 and
1500 cd/m²
Perceived video quality increases with peak
luminance level (20 points between
300 and 1500 cd/m2)
4EVER-2 : go for UHD-TV phase 2!
HDR: a good improvement… soon? High Dynamic Range: sequences look more natural, sensation of immersion
– Better contrasts: better dark areas, better bright areas
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 21
Focus on HDR
www.4ever-2.com 22 4EVER-2 : go for UHD-TV phase 2!
23 www.4ever-2.com
High Dynamic Range (HDR)
• Increased contrast • Bright areas (e.g. > 1000 nits) , Dark areas (e.g. < 0.001 nits)
• Luminance range rendering closer to the real world luminance range
• HDR vs SDR higher gain than UHD vs HD • Perceived video quality increases with peak luminance level
High Dynamic Range Standard Dynamic Range
Simulation
1 nit = 1 candela/m2
4EVER-2 : go for UHD-TV phase 2!
24 www.4ever-2.com
Today’s Standard Dynamic Range (SDR)
24
~ 0,2 – 1
Lux
> 30 000
OETF: Opto-Electrical Transfer Function
EOTF: Electro-Optical Transfer Function
Lum in cd/m2 or nits
8 bits signal
4EVER-2 : go for UHD-TV phase 2!
25 www.4ever-2.com
OETF, EOTF & OOTF
Scene Luminance (min. 10-6 nits / max. 108 nits)
Display Luminance (min. 10-3 nits / max. > 103
nits)
Electro-Optical Transfer Function
(EOTF)
Opto-Electronical Transfer Function
(OETF)
Opto-Optical Transfer Function (OOTF)
4EVER-2 : go for UHD-TV phase 2!
26 www.4ever-2.com
HDR: “New” Opto Electronic Transfer Function (OETF)
• “Old” gamma correction => Not well-adapted to wider dynamic range
• PQ (Perceptual Quantizer - SMPTE ST 2084) => Luminance vs Code Value (display referred)
4EVER-2 : go for UHD-TV phase 2!
27 www.4ever-2.com
HDR: Grading and Settings
• Color grading (tuning RGB levels, Hue, Brightness, Saturation, and Contrast) => Artistic intent
• HDR content color grading relies on a set of parameters • Which OETF? ST-2084, HLG or proprietary Transfer Function
• Color gamut or primaries? BT 709, P3, BT 2020, XYZ,…
• White primaries? C, D65,…
• Min brightness value?
• Max brightness value?
• Grading monitor characteristics?
To make the viewing experience match the original “Artistic intent”, HDR color grading information must be known at the display side: metadata
Sources: BlackMagic Davinci Resolve
4EVER-2 : go for UHD-TV phase 2!
28 www.4ever-2.com
HDR: what about backward compatibility?
• HDR backward compatibility with SDR is an hot topic!
• Several meanings! • Same workflows? cameras, encoders, post-production, etc… • Same spatial resolution? Same bitdepth?
• What is the real need? • One HDR signal directly watchable on any SDR display • One signal from which we can extract both HDR and SDR signal • One HDR signal and one SDR signal simulcasted
• 2 answers: • Compatibility with UHD phase 1 • Compatibility with “today” HDTV (HD,709)
4EVER-2 : go for UHD-TV phase 2!
29 www.4ever-2.com
HDR in a nutshell
• New Transfer Function • To better match human visual perception at high luminance
• HDR video signal grading • Color Gamut/primaries and grading based on OETF/EOTF
• Backward compatibility
• Metadata? • Artistic intent: to properly render the HDR signal whatever the technical characteristics
of your HDR display
• Backward compatibility: to reconstruct HDR and/or SDR signal from the encoded content
4EVER-2 : go for UHD-TV phase 2!
30 www.4ever-2.com
Alternative HDR Solutions • In addition to HDR10/PQ: Philips, Technicolor, Dolby and, NHK/BBC alternative solutions
• OETF: New transfer functions
• Single or Dual layer
• Metadata (static, dynamic)
• SDR (Standard Dynamic Range) backward compatibility
Provider OETF Method Metadata Backward
Compatible Layers
1 BDA/HDR 10 PQ HDR (SL) Static No Single
2 BBC/NHK HLG OETF (SL) No Yes Single
3 Philips/Technicolor -1 PQ HDR (BL) Static + Dynamic Yes (with IP) Single
4 Philips/Technicolor-2 PQ SDR (BL) Static + Dynamic Yes Single
5 Dolby Vision-1 PQ HDR (BL) +EL Static + Dynamic Yes (with IP) Dual
6 Dolby Vision-2 PQ SDR (BL) + EL Dynamic Yes (with IP) Dual
4EVER-2 : go for UHD-TV phase 2!
31 www.4ever-2.com
On HLG - Hybrid Log-gamma
• Transfer function proposed by BBC/NHK (Scene referred)
EOTF: PQ vs BT 1886 (SDR) vs HLG
4EVER-2 : go for UHD-TV phase 2!
32 www.4ever-2.com
HDR Eco-System Standardization Status (1/2)
• OETF • PQ - SMPTE ST 2084
• HLG- ARIB STD-B67
• Metadata • SMPTE ST 2086: define standard color grading display metadata
• SMPTE ST 2094: dynamic metadata describing transformation HDR <->SDR (On-going)
• HDMI • 2.0a: Support standard ST 2084 + metadata ST 2086
• 2.1: Hybrid Log Gamma (HLG), ST 2094 ?
• IMF • metadata ST 2086 support soon
4EVER-2 : go for UHD-TV phase 2!
33 www.4ever-2.com
HDR Eco-System Standardization Status (2/2)
• Blu-Ray Disc Association (BDA) • HDR 10: HEVC main 10-bits + ST-2084 + ST-2086 Metadata
• Optional: Proprietary metadata: Dolby, Philips, Technicolor
• Compression and application standardization • MPEG/ITU HEVC:
• VUI values for PQ and HLG • SEI messages:
• ARIB: standardized the usage of HLG: STD B67
• DVB: PQ, HLG, Dolby under consideration
Mastering Display Colour Volume (ST 2086),
Chroma resampling filter hint,
Knee function information,
Colour Remapping Information
Content Light Level Information
HDR Compatibility Information
4EVER-2 : go for UHD-TV phase 2!
Recent 4EVER-2 HDR live trials
set up real live TV production and distribution
www.4ever-2.com 34 4EVER-2 : go for UHD-TV phase 2!
Backward compatibility in TV production
• Main drawback of PQ is that it is not SDR backward compatible – SDR and HDR shall be simulcasted
• The goal is to produce HD 709 + Ultra HD Phase 1 709 or 2020 and add HDR in the same workflow
• With few extra costs !
– no additional cameras
– using current technology (SDI 10 bits …)
– with few extra charge for production teams
• Because TV distribution will remain mostly HD 709 at least for a number of years!
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 35
Candidates for TV production in HDR
1. Each camera outputs two (independent) signals – one HD/UHD phase1
– one PQ 10
– vision engineering can optimize SDR and HDR separately
2. Hybrid Log Gamma – HDR and SDR are controled using one video signal
– vision engineering shall optimize SDR and HDR jointly
3. HDR or SDR + Metadata ? – in a static or dynamic way?
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 36
1/ Live sport in HDR and HFR Figure ice skating:
HDR for brightness on ice and costumes,
HFR for figure motion
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 37
• But, 13/11/2015 in France … experimentation shortened, only HDR tested
• 2 different cameras, one at a time - GrassValley LDX - Sony HDC4300
• 4K zooms: Fujinon 80x (UA80X9BE)
13-14 November 2015
Bordeaux, France
1/ Live sport in HDR
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 38
• 1st test (LDX) => a single camera to generate two streams: one HDR and one SDR
• 2nd test => an HDR-PQ camera (Sony 4300) and a SDR camera on a rig (Sony 2400)
• Remote control from production truck
• HDR and SDR comparisons
1/ Live sport in HDR
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 39
Production truck:
simulation of what will be next, when…
…here!
An extremely valuable experimentation, very own production space for HDR camera remote control
1/ Live sport in HDR
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 40
Many lessons learned on where difficulties are: how to control SDR and
HDR independently, yet in a single production?
2/ Bastille Opera live HDR production A single production to serve both HDR and non HDR: use of HLG technology
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 41
15 December 2015
Bastille Opera,
Paris France
2/ Bastille Opera live HDR production
www.4ever-2.com 42
HDR monitoring
709 monitoring
709 color gamut
Quad 3G SDI 4K HLG
Quad 3G SDI 4K HLG
downsizing
HD 709
vision engineer focus in SDR, then control HDR result
potential 709 graphics mapped to HLG with LUT
for instance towards HEVC encoder with
HLG signaling
for instance towards H264 encoder
4EVER-2 : go for UHD-TV phase 2!
709 monitoring OBvan HD signal
Sony 4300 (HLG prototype version) zoom Canon 90x (J90x9B)
Our HLG workflow, generating both
4K-HDR and HD-SDR
for comparison to broadcasted commercial
HDTV signal
2/ Bastille Opera live HDR production
www.4ever-2.com 43 4EVER-2 : go for UHD-TV phase 2!
Comparison between HD and UHD + HDR
www.4ever-2.com 44 4EVER-2 : go for UHD-TV phase 2!
A big success for invited producers and directors of photography:
loved both the SDR quality and the HDR potential
2/ Bastille Opera live HDR production
www.4ever-2.com 45 4EVER-2 : go for UHD-TV phase 2!
Despite tough content parameters…
2/ Bastille Opera live HDR production
Ultra HD phase 2
focus on HFR
www.4ever-2.com 46 4EVER-2 : go for UHD-TV phase 2!
HFR vs. TV set « sport mode »
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 47
High Frame Rate
50 frames / s transmission
100 frames / s transmission
Display interpolation
("sport mode")
Why doesn’t interpolation work well? • Frame interpolation (refreshment) does not always work
• Refreshment invents content => artefacts will happen: object is doubled, blurry, disappears, …
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 48
Refreshment as displayed on good consumer TV sets
(HD 1080p50, HEVC 7Mbps)
- Collaborative work with EBU, BBC and IRT (BTF HFR)
- Evaluate the added value of 100Hz in comparison with 50Hz in terms of perceived
video quality
- Uncompressed contents
- Compressed contents
- Using HEVC at 3 Mbps (BBC contribution)
- MCFI professional solution
- Using Alchemist OD (IRT contribution)
CONTEXT AND TEST OBJECTIVE
- SAMVIQ (ITU-R BT. 1788)
- Global notation for short duration clips
- Continuous quality scale (0-100) using quality items
- Bad, Poor, Fair, Good and Excellent
- Use of explicit and/or hidden references
- Observers
- Non-expert viewers
- Normal screening
- Rejection criteria used for results analysis
SUBJECTIVE TEST METHOD
VIEWING ENVIRONMENT
- Based on Recommendation ITU-R BT. 500
- Background luminance vs display peak luminance
- Viewing distance
- Room colors
TEST ORGANIZATION
- Viewing environment
- Viewing distance: 3H (2m)
- Background: 10% of the display peak luminance
- Test setup
- Subjective quality assessment software (Orange Labs tool)
- PC-based player: HP Z820, Matrox DSX LE4
- 55-inch HFR display (Mikrom): 4 x 3G-SDI (HD, 200/240p)
- 31 observers
- Non-experts
- Normal screening
TEST MATERIAL (1)
- 5 contents (sources)
- HD format (1920x1080p200, 16 seconds)
- Different motion features (camera motion, etc.)
BBC4
EBU
BBC9
BBC3
4EVER
TEST MATERIAL (2)
- 6 test conditions: 3 frame rates, 2 shutter values
- Test 1: uncompressed contents
- Test 2: compressed contents at 3 Mbps (HEVC)
200Hz 100%
Averaging 100Hz 100%
Averaging 50Hz 100%
Down sampling
50Hz 50%
MCFI 50 to 100Hz From 50Hz(50%)
MCFI 50 to 100Hz From 50Hz(100%)
Frame rate Shutter
RESULTS: UNCOMPRESSED CONTENTS
100Hz native contents provide better quality than 50Hz native contents (about 20 points)
Frame rate : Shutter :
RESULTS: UNCOMPRESSED CONTENTS
Frame rate : Shutter :
Frame rate : Shutter :
Frame rate : Shutter :
Frame rate : Shutter :
Frame rate : Shutter :
RESULTS: COMPRESSED CONTENTS (3 MBPS)
100Hz native contents provide better quality than 50Hz native contents (about 15 points)
Frame rate : Shutter :
RESULTS: COMPRESSED CONTENTS (3 MBPS)
MAIN CONCLUSIONS
- 100Hz native contents provide much better perceived video quality than 50Hz native ones
- The performance of Interpolation (MCFI) depends on the content’s motion features
- In the worst cases, the perceived video quality is lower than 50Hz native ones (visual
artefacts)
- In the best cases, the perceived video quality can reach the 100Hz native ones
- Best performances at 50% shutter vs 100%
- In average, 50Hz interpolated at 100Hz cannot reach the perceived video quality of native
100Hz
- At the same bitrate, the perceived quality of a 100Hz source remains better than a 50Hz
source (interpolated or not).
live HFR + HDR workflow
www.4ever-2.com 61
HDR monitoring
709 monitoring
709 color gamut
8x 3G SDI 4K HLG HFR
8x 3G SDI 4K HLG HFR
downsizing
HD 709 HFR
709 graphics upsampled to 4K HFR
HEVC encoder with HLG signaling
HEVC encoder
HD 709
frame averaging
H264 encoder
4K 709
frame averaging
HEVC encoder
WCG can also be introduced with extra complexity
? how to sync successive frames
4EVER-2 : go for UHD-TV phase 2!
Compressor challenges
www.4ever-2.com 62 4EVER-2 : go for UHD-TV phase 2!
63 4EVER-2 : go for UHD-TV phase 2! www.4ever-2.com
Compressor challenges
• Metadata feeding • Static/dynamic metadata • No standard methods: IMF, Side XML, VANC, others… • Metadata generation in the encoder?
• Content preparation • Chroma Subsampling/downscaling • Pre-processing • Color space conversion
• Compression • HDR Signal properties => new video defects may appear • Chroma and luma errors • 10-bit banding and contouring
64 4EVER-2 : go for UHD-TV phase 2! www.4ever-2.com
HDR adapted content processing
OETF is highly non-linear => Non-Linear algorithms have to be implemented
• Chroma sub-sampling • HEVC Main 10 encodes 4:2:0 chroma samples
• Source is usually RGB 4:4:4 =>Sub-sampling has to be performed prior to encoding
• Conventional approaches can not be used => need to take transfer function characteristics into account
Y components
U,V components
R,G,B components
65 4EVER-2 : go for UHD-TV phase 2! www.4ever-2.com
Color Processing Pipeline
66 4EVER-2 : go for UHD-TV phase 2! www.4ever-2.com
Halos and chroma shifts
• Problem caused by the steep EOTF curve at high luminance
• For instance: • An error of 16 in code value
(1.5% of the full scale)
• => a luminance error of 123 nits (10% of the full scale)
67 4EVER-2 : go for UHD-TV phase 2! www.4ever-2.com
Small errors cause large defects • Strong mosquito noise and chroma errors around bright edges
• Caused by quantization error spreading in blocks
Small area of a HDR source picture Compressed result
68 4EVER-2 : go for UHD-TV phase 2! www.4ever-2.com
Avoid error spreading
• Take advantage of HEVC coding tree
• Small TU on bright edges for visual improvement
PU
TU
64x64 8x8
CU
69 4EVER-2 : go for UHD-TV phase 2! www.4ever-2.com
Banding artifacts
• Most annoying and frequent visual defect when compressing HDR content
• Appears in unexpected areas even at high bit-rate
Area exhibiting banding
Luminance map
70 4EVER-2 : go for UHD-TV phase 2! www.4ever-2.com
Barten ramp vs 10/11-bit PQ
• Barten ramp gives an indication of minimum visible contrast step
• One code value change in 10-bit may be visible, not in 11-bit
0.1%
1%
10%
0.001 0.01 0.1 1 10 100 1000 10000
Min
imu
m C
on
tras
t St
ep
(%
)
Luminance (cd/m2)
Barten Ramp
10-bit ST-2084 PQ
11-bit ST-2084 PQ
71 4EVER-2 : go for UHD-TV phase 2! www.4ever-2.com
Contrast visibility
• All common 10-bit EOTF perform about the same
• One code value change in 10-bit may be visible with all EOTF
0.1%
1%
10%
0.01 0.1 1 10 100 1000 10000
Min
imu
mC
on
tras
t St
ep
(%
)
Luminance (cd/m2)
Barten Ramp
10-bit ST-2084 PQ
10-bit ARIB-B27 1200nits
10-bit BT.709 200nits
72 4EVER-2 : go for UHD-TV phase 2! www.4ever-2.com
On noise encoding
• Avoiding banding artifacts is performed by adding dithering noise on the source
• But HEVC, H.264 and MPEG-2 are not efficient on noise
• The video codec tends to remove dithering noise leading to banding
73 4EVER-2 : go for UHD-TV phase 2! www.4ever-2.com
How the encoder can help?
• Detect areas prone to banding an improve PSNR as much as possible
• Add strong in-loop dithering noise prior to encode in relevant areas
• Use Film Grain technology (generate noise on the receiver side) when available
• Or increase contrast and add a stronger dithering noise un post-production…but…
ST-2084 BT.709
74 4EVER-2 : go for UHD-TV phase 2! www.4ever-2.com
Bitrate impacts
• PQ + metadata solution • HDR only
• HDR10 + metadata : very few bytes on GOP or scene basis
• Backward compatible • SDR + metadata => SDR base layer is encoded with increased bitrate of around 5%
• HLG solution • No bitrate overhead => further experiments
Dolby Vision Solution • Backward compatible
• Base Layer (either SDR or HDR) + Enhancement Layer => EL bitrate is ¼ of the base layer bitrate
Realisation of the first UHD-TV phase 2 TV clip
Using all UHD-TV phase 2 technologies
(4K, HFR, HDR, WCG) plus NextGen Audio
www.4ever-2.com 75 4EVER-2 : go for UHD-TV phase 2!
First fiction in UHD-TV phase 2 + 3D audio
www.4ever-2.com 76 4EVER-2 : go for UHD-TV phase 2!
4-7 November 2015
Paris, France
« 4EVER short »,
« Une danse pour la vie »
Quote from the author
« All the technical tools to define tomorrow’s TV have
a common goal: researching viewer immersion. This
short story narrative goes the same way, immerging
the audience into emotion »
Fiction in 4K, HDR, HFR, WCG and 3D audio
www.4ever-2.com 77 4EVER-2 : go for UHD-TV phase 2!
Bright lights in motion at night…
Motion inside a structure
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 78
Ultra High Technology to serve artistic intention, taking into account the power of the story
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 79
All about lights and contrast
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 80
Director of photography
and HDR experts team
Watch the making-of http://www.dailymotion.com/video/x3iw04w_4evershort_tv
Conclusions and perspectives
www.4ever-2.com 81 4EVER-2 : go for UHD-TV phase 2!
HDR: high expectations… still some issues • No bitrate defined yet
– New nature of the video signal impacts encoder performance
• Current HDR TV sets are first generation
– Between 500 and 1000 cd/m² in 2015 (target = 1500 cd/m²)
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 82
• No standards yet, too many options
– Transfer functions (EOTF) => Dolby PQ, BBC/NHK HLG
– Format: 1 or 2 layers? Metadata or not? => Technicolor, Dolby, Philips
– Encoding: HEVC Main 10 or future MPEG technology
But live production can be operational pretty soon!
HFR: nearly ready, yet some issues • is 8xSDI manageable?
• monitoring in 50p and mix in 100p?
• sync issues – how to sync 2x 50 Hz SDI feeds?
• 100Hz clock?
• 50 Hz clock? If two feeds have a 50hz clock, which one is first? Can synch be based on odd/even frames?
– how to apply DVE to SDI feeds with same timestamps
• ie: how to fade two pictures at the same time but with different fading parameters?
• is it possible to add a delay of 10 ms for one picture effect?
• instant replay / slow motion in 4K 100 ?
– capture in 4K 300fps???
– interpolation?
• HD HFR production is probably a better alternative….
www.4ever-2.com 83 4EVER-2 : go for UHD-TV phase 2!
Technology impact on perceived quality
• Video subjective tests target in 2016 – HDR
• Comparison of solutions in terms of perceived video quality
• Impact of compression on HDR perceived video quality
– HFR • Impact of HFR on 4K resolution in terms of perceived video quality
• but displays?
– HFR + HDR • Impact of HFR + HDR combination in terms of perceived video quality
• NextGen Audio with UHD-Phase 2: tests end 2016/2017 www.4ever-2.com 84 4EVER-2 : go for UHD-TV phase 2!
Towards live HDR - WCG - HFR - 4K • Continue independent evaluations of
– Technology (visual assessments)
– Equipment : characterization of displays or cameras
– End-to-end workflow
• Promote HFR: a major added value for the first to jump in, a great way to differentiate
• Shoot sequences ourselves: complete parameter control and rights – Feb/Mar16: tbd – second HDR test – distribution trial
• Visible events – Apr16: HD/4K/HDR live production and distribution
– Jun/Jul16: Sports - HD/4K HDR/HD HFR live production and distribution test
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 85
Towards live HDR - HFR - 4K • Disseminate results in standardization committees
and conferences – DVB, ITU, MPEG, SMPTE
– For information to be where and when people make decisions, worldwide
– Selected for NAB2016 Futures Parks;
– IBC2016 FutureZone?
• Collaborations – display/camera manufacturers and everyone welcome!
www.4ever-2.com 4EVER-2 : go for UHD-TV phase 2! 86
Merci ! Thank you!
www.4ever-2.com
maryline.clare @orange.com
Appendices
www.4ever-2.com 88 4EVER-2 : go for UHD-TV phase 2!
HDR and WCG workflows
for TV production and distribution
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Prepare for a live UHD-HDR production
• Which camera and attached processors?
• Which HDR-SDR workflow?
• Which methodology for vision engineers?
• Which additional cost compared to HD, compared to UHD phase 1?
• How convince producers, and their photographers?
www.4ever-2.com 90 4EVER-2 : go for UHD-TV phase 2!
Backward compatibility in TV production
• The goal is to produce HD 709 + Ultra HD Phase 1 709 or 2020 and add HDR in the same workflow
– Adding HFR is also a must have, especially for sports!
• With few extra costs !
– no additional cameras
– using current technology (SDI 10 bits …)
– with few extra charge for production teams
• because TV distribution will remain mostly HD 709 at least for a number of years!
www.4ever-2.com 91 4EVER-2 : go for UHD-TV phase 2!
?
PQ/709 OETF + WCG/709 workflow
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2020/P3 gamut 4K
HDR OETF
709 gamut HD or 4K 709 OETF
3DLut WCG 2020/P3 to 709
Quad 3G SDI 4K PQ WCG
Quad 3G SDI 4K 709 WCG
Quad 3G SDI 4K PQ WCG
Quad 3G SDI 4K 709 WCG
3DLut downsizing
HD 709
common settings ? 709 specific ? PQ specific ?
709 graphics mapped in WCG with LUT, 4K or
upsampled
Quad 3G SDI 4K 709 3DLut
HDR 10 encoder
HEVC encoder
H264 encoder
HEVC encoder
+ « fast track » Backward Compatible encoder?
mastering information
4EVER-2 : go for UHD-TV phase 2!
?
HLG OETF + 709 workflow
www.4ever-2.com 93
HDR monitoring
709 monitoring
709 color gamut
Quad 3G SDI 4K HLG
Quad 3G SDI 4K HLG
downsizing
HD 709
common settings ? SDR vs HDR tradeoff? 709 graphics
mapped to HLG with LUT
HEVC encoder with HLG signaling
H264 encoder
4EVER-2 : go for UHD-TV phase 2!
?
HLG OETF + WCG workflow
www.4ever-2.com 94
HDR monitoring
709 monitoring
WCG color gamut
Quad 3G SDI 4K HLG WCG
Quad 3G SDI 4K HLG
downsizing
HD 709
common settings ? SDR vs HDR tradeoff? 709 graphics
mapped to HLG WCG using LUT
HEVC encoder with HLG signaling
H264 encoder 3DLut
WCG to 709
3DLut WCG to 709
static color remapping metadata
4EVER-2 : go for UHD-TV phase 2!
live HDR workflow issues Camera Paint menu operations
• PQ vs 709
– common parameters: iris, color temp, details, noise, ..?
– separate parameters: gamma/knee, max lum, blacks ? others?
• HLG
– how to make a tradeoff between SDR efficiency and HDR efficiency? using knee point, max luminance? others?
• in both cases, some colorimetry mismatch should also be addressed, mainly for skin tones
• and of course camera sensor dynamic is essential! www.4ever-2.com 95 4EVER-2 : go for UHD-TV phase 2!