ETSI TS 103 433-2 V1.1.1 (2018-01)

TECHNICAL SPECIFICATION
High-Performance Single Layer High Dynamic Range (HDR)
System for use in Consumer Electronics devices;
Part 2: Enhancements for Perceptual Quantization (PQ)
transfer function based High Dynamic Range (HDR)
Systems (SL-HDR2)
2 ETSI TS 103 433-2 V1.1.1 (2018-01)

Reference
DTS/JTC-040-2
Keywords
broadcasting, content, digital, distribution, HDR,
HDTV, UHDTV, video
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3 ETSI TS 103 433-2 V1.1.1 (2018-01)
Contents
Intellectual Property Rights . 5
Foreword . 5
Modal verbs terminology . 5
Introduction . 5
1 Scope . 8
2 References . 8
2.1 Normative references . 8
2.2 Informative references . 8
3 Definitions, symbols, abbreviations and conventions . 9
3.1 Definitions . 9
3.2 Symbols . 10
3.2.1 Arithmetic operators . 10
3.2.2 Mathematical functions . 11
3.3 Abbreviations . 11
3.4 Conventions . 12
4 End-to-end system . 12
5 HDR system architecture. 13
6 Dynamic metadata format for HDR-to-HDR/SDR adaptation . 13
7 HDR-to-HDR/SDR signal reconstruction process . 15
7.1 Input streams . 15
7.2 Reconstruction process of an SDR or HDR stream . 15
7.2.1 Introduction. 15
7.2.2 Selecting a reconstruction mode . 16
7.2.3 Luminance mapping and colour correction tables construction . 17
7.2.3.1 Luminance mapping table construction from variables (payloadMode 0) . 17
7.2.3.1.1 Introduction . 17
7.2.3.1.2 Overview of the computation of lutMapY . 17
7.2.3.1.3 Block "To perceptual uniform signal" . 18
7.2.3.1.4 Block "Black/white level adaptation" . 18
7.2.3.1.5 Block "Tone mapping curve" . 19
7.2.3.1.6 Block "Adjustment curve" . 21
7.2.3.1.7 Block "Gain limiter" . 22
7.2.3.1.8 Block "To linear signal" . 23
7.2.3.1.9 Block "Inverse EOTF" . 23
7.2.3.2 Colour correction table construction from parameter-based mode (payloadMode 0) . 23
7.2.3.3 Luminance mapping table retrieval (payloadMode 1) . 24
7.2.3.4 Colour correction table retrieval (payloadMode 1) . 25
7.2.4 HDR/SDR picture reconstruction from look-up tables and HDR picture . 25
7.3 Metadata recomputation for presentation display adaptation . 27
7.3.1 Introduction. 27
7.3.2 Scaling factor computation . 27
7.3.3 Recomputation for "Black/white level adaptation" parameters . 28
7.3.4 Recomputation for "Tone mapping curve" parameters . 28
7.3.5 Recomputation for "Adjustment curve" parameters . 29
Annex A (normative): SL-HDR reconstruction metadata using HEVC . 31
Annex B (normative): SL-HDR reconstruction metadata using AVC . 32
Annex C (informative): HDR-to-SDR decomposition principles and considerations . 33
Annex D (informative): Gamut mapping . 34
ETSI
4 ETSI TS 103 433-2 V1.1.1 (2018-01)
Annex E (informative): Embedded data on CE digital video interfaces . 35
E.1 Introduction . 35
E.2 Supported video formats . 35
E.3 Metadata packets . 35
E.3.1 Introduction . 35
E.3.2 Metadata packet syntax . 35
E.3.3 Metadata packet semantics . 36
E.3.4 Metadata packet embedding . 37
E.4 Graphics Indicator bit . 37
E.5 Signalling SL-HDR Dynamic Metadata . 38
E.5.1 Introduction . 38
E.5.2 VSVDB to signal SL-HDR support . 38
E.5.3 SL-HDR Dynamic Metadata InfoFrame . 38
Annex F (informative): Error-concealment: recovery in post-processor from metadata loss or
corruption . 40
F.1 Introduction . 40
F.2 Metadata values for recovery mode . 40
F.3 Recovery of shadow_gain_control with MDCV SEI message . 41
F.4 Recovery of shadow_gain_control without MDCV SEI message . 41
Annex G (informative): ETSI TS 103 433 signalling in CTA-861-G. 42
Annex H (informative): Minimum and maximum value of L for display adaptation . 43
pdisp
Annex I (informative): Change History . 44
History . 45

ETSI
5 ETSI TS 103 433-2 V1.1.1 (2018-01)
Intellectual Property Rights
Essential patents
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (https://ipr.etsi.org/).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Trademarks
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ETSI claims no ownership of these except for any which are indicated as being the property of ETSI, and conveys no
right to use or reproduce any trademark and/or tradename. Mention of those trademarks in the present document does
not constitute an endorsement by ETSI of products, services or organizations associated with those trademarks.
Foreword
This Technical Specification (TS) has been produced by ETSI 3rd Generation Partnership Project (3GPP).
The present document is part 2 of a multi-part deliverable. Full details of the entire series can be found in part 1 [1].
NOTE: The EBU/ETSI JTC Broadcast was established in 1990 to co-ordinate the drafting of standards in the
specific field of broadcasting and related fields. Since 1995 the JTC Broadcast became a tripartite body
by including in the Memorandum of Understanding also CENELEC, which is responsible for the
standardization of radio and television receivers. The EBU is a professional association of broadcasting
organizations whose work includes the co-ordination of its members' activities in the technical, legal,
programme-making and programme-exchange domains. The EBU has active members in about
60 countries in the European broadcasting area; its headquarters is in Geneva.
European Broadcasting Union
CH-1218 GRAND SACONNEX (Geneva)
Switzerland
Tel: +41 22 717 21 11
Fax: +41 22 717 24 81
Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of
provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
Introduction
Motivation
Today High Efficiency Video Coding (HEVC) enables first Ultra HD broadcast services (also referred as "4K"
resolution) via existing DVB specifications.
ETSI
6 ETSI TS 103 433-2 V1.1.1 (2018-01)
The goal of ETSI TS 103 433-1 [1] V1.2.1, SL-HDR1, was to standardize a single layer HDR system addressing direct
backwards compatibility i.e. a system leveraging SDR distribution networks and services already in place and that
enables high quality HDR rendering on HDR-enabled CE devices including high quality SDR rendering on SDR CE
devices.
The goal of the present document is to specify enhancements for single layer Perceptual Quantization (PQ) transfer
function based HDR systems, enabled by signal processing blocks that are similar/the same to those in SL-HDR1.
Similar to SL-HDR1, these enhancements will be enabled by use of dynamic metadata and a post processor in the
Consumer Electronics device.
Pre-processing
At the distribution stage, an incoming HDR signal is analysed and content-dependent dynamic metadata is produced.
This dynamic metadata can be produced in an automatic process or in a manual process where the image quality
resulting of the metadata that has been set manually is judged on an SDR grading monitor. This dynamic metadata can
be used to create an optimal picture for a display that has different characteristics, most noticeably a different maximum
luminance, than the display used when grading the HDR content. The HDR signal is encoded with any distribution
codec (e.g. HEVC as specified in part 1 [1], Annex A) and carried throughout an HDR distribution network with
accompanying metadata conveyed on a specific channel or embedded in an HDR bitstream. The dynamic metadata can
for instance be carried in an SEI message when used in conjunction with an HEVC codec. The pre-processor that
produces dynamic metadata is not a normative requirement of the present document. Nonetheless, the pre-processor is
expected to produce a dynamic metadata stream matching the syntax specified in Annex A and Annex B.
Post-processing
The post-processing stage occurs just after HDR bitstream decoding. The post-processing takes as input an HDR video
frame and associated dynamic metadata and the characteristic of the attached HDR compliant rendering device in order
to optimize the HDR picture for the rendering device as specified in clause 7.
Structure of the present document
The present document is structured as follows. Clause 1 provides the scope of the current document. Clause 2 provides
references used in the present document. Clause 3 gives essential definitions, symbols and abbreviations used in the
present document. Clause 4 provides information on the end to end system. Clause 5 details the architecture of the HDR
system. Clause 6 specifies the format of the content-based dynamic metadata common to systems based on ETSI TS
103 433 multi-part documents. Specifically to the present document, the metadata are produced during the HDR-to-
SDR decomposition stage and they enable reconstruction of the SDR signal from the decoded HDR signal using those
metadata. Clause 7 specifies the reconstruction process of the SDR signal and an HDR signal that is adapted to the
maximum luminance of the presentation display. The dynamic metadata format specified in clause 6 is normatively
mapped from SEI messages representative of SL-HDR system that are specified for HEVC and AVC respectively in
Annex A and Annex B. Informative Annex C and Annex D provide information on an HDR-to-SDR decomposition
process, and a gamut mapping process. Informative Annex E describes a way to transfer dynamic metadata by
embedding it in the video transferred over a CE digital video interface. Informative Annex F proposes a recovery
procedure when dynamic metadata are detected as missing by the post-processor during the HDR signal reconstruction.
The recovery procedure may also be applied in case it is desirable to replace the original metadata by a fixed tone
mapping function, e.g. when graphics overlays are inserted on the decoded video by a mid-device (e.g. STB) which
transmits SL-HDR reconstruction metadata as well as the mixed video to an SL-HDR capable TV. Eventually,
informative Annex G gives reference to a standard mechanism to carry SL-HDR reconstruction metadata through
interfaces and Annex H provides a recommendation on the maximum presentation display luminance that display
adaptation can be used with.
The structure of the present document is summarized in Table 1.
ETSI
7 ETSI TS 103 433-2 V1.1.1 (2018-01)
Table 1: Structure of the present document
Clause/Annex # Descriptionfigure Normative/Informative
(in the present document)
Clause 1 Scope of the document Informative
Clause 2 References used in the document Normative/Informative
Clause 3 Definitions, symbols, abbreviations Informative
Clause 4 End-to-end system Informative
Clause 5 Architecture of the HDR system Informative
Clause 6 Metadata format abstraction layer (agnostic to the Normative
distribution format)
Clause 7 HDR-to-HDR/SDR reconstruction process Normative
Annex A SL-HDR reconstruction metadata using HEVC Normative
Annex B SL-HDR reconstruction metadata using AVC Normative
Annex C HDR-to-SDR decomposition principles and Informative
considerations
Annex D Gamut mapping Informative
Annex E Embedded data on CE digital video interfaces Informative
Annex F Error-concealment and recovery procedure Informative
Annex G ETSI TS 103 433 signalling in CTA-861-G Informative
Annex H Minimum and maximum value of for display Informative
adaptation
ETSI
8 ETSI TS 103 433-2 V1.1.1 (2018-01)
1 Scope
The present document specifies the HDR-to-HDR/SDR content-based dynamic metadata and the post-decoding process
enabling reconstruction from the specified metadata and an HDR signal of an SDR signal (100 cd/m or less) or an
HDR signal with a maximum luminance ranging from 100 cd/m to a maximum luminance that is higher than that of
the original HDR signal. This reconstruction process is typically invoked in a Consumer Electronics device such as a
TV set, a smartphone, a tablet, or a Set Top Box. Besides, it provides information and recommendations on the usage of
the described HDR system.
2 References
2.1 Normative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
referenced document (including any amendments) applies.
Referenced documents which are not found to be publicly available in the expected location might be found at
https://docbox.etsi.org/Reference/.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long term validity.
The following referenced documents are necessary for the application of the present document.
[1] ETSI TS 103 433-1 (08-2017): "High-Performance Single Layer High Dynamic Range (HDR)
System for use in Consumer Electronics devices; Part 1: Directly Standard Dynamic Range (SDR)
Compatible HDR System (SL-HDR1)".
[2] Recommendation ITU-R BT.709-6 (06-2015): "Parameter values for HDTV standards for
production and international programme exchange".
[3] Recommendation ITU-R BT.2020-2 (10-2015): "Parameter values for ultra-high definition
television systems for production and international programme exchange".
[4] Recommendation ITU-T H.264 (04-2017): "Advanced video coding for generic audiovisual
services".
[5] Recommendation ITU-T H.265 (12-2016): "High efficiency video coding".
[6] SMPTE ST 2084:2014: "High Dynamic Range Electro-Optical Transfer Function of Mastering
Reference Displays".
[7] SMPTE ST 2086:2014: "Mastering Display Color Volume Metadata Supporting High Luminance
and Wide Color Gamut Images".
2.2 Informative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
referenced document (including any amendments) applies.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long term validity.
ETSI
9 ETSI TS 103 433-2 V1.1.1 (2018-01)
The following referenced documents are not necessary for the application of the present document but they assist the
user with regard to a particular subject area.
[i.1] CTA Standard CTA-861.3, January 2015: "HDR Static Metadata extensions".
[i.2] CTA Standard CTA-861-G, November 2016: "A DTV Profile for Uncompressed High Speed
Digital Interfaces".
[i.3] Recommendation ITU-R BT.2035: "A reference environment for evaluation of HDTV program
material or completed programmes".
[i.4] Ross N. Williams: "A Painless Guide to CRC Error Detection Algorithms," Version 3, 19 August
1993.
NOTE: Available at http://www.ross.net/crc/crcpaper.html.
[i.5] SMPTE Engineering Guideline EG 28-1993: "Annotated Glossary of Essential Terms for
Electronic Production".
[i.6] SMPTE ST 2094-20:2016: "Dynamic Metadata for Color Volume Transform - Application #2".
[i.7] SMPTE ST 2094-30:2016: "Dynamic Metadata for Color Volume Transform - Application #3".
[i.8] ETSI TS 103 433 (all parts): "High-Performance Single Layer High Dynamic Range (HDR)
System for use in Consumer Electronics devices".
3 Definitions, symbols, abbreviations and conventions
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
colour correction: adjustment of the luma and chroma components of a signal derived from the HDR signal in order to
avoid hue shift and preserve the colour look of the HDR signal in the SDR signal
colour volume: solid in colorimetric space containing all possible colours a display can produce
decomposed picture: SDR picture derived from the HDR-to-SDR pre-processing stage
NOTE: Type of pre-processed picture.
display adaptation: adaptation of a video signal to the characteristics of the targeted Consumer Electronics display
(e.g. maximum luminance of the CE display)
dynamic metadata: metadata that can be different for different portions of the video and can change at each associated
picture
gamut: complete subset of colours which can be represented within a given colour space or by a certain output device
NOTE: Also known as colour gamut.
gamut mapping: mapping of the colour space coordinates of the elements of a source image to colour space
coordinates of the elements of a reproduction
NOTE: Gamut mapping intent is not to change the dynamic range of the source but to compensate for differences
in the source and output medium colour gamut capability.
High Dynamic Range (HDR) system: system specified and designed for capturing, processing, and reproducing a
scene, conveying the full range of perceptible shadow and highlight detail, with sufficient precision and acceptable
artefacts, including sufficient separation of diffuse white and specular highlights
luma: linear combination of non-linear-light (gamma-corrected) primary colour signals
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10 ETSI TS 103 433-2 V1.1.1 (2018-01)
luminance: objective measure of the visible radiant flux weighted for colour by the CIE Photopic Spectral Luminous
Efficiency Function [i.5]
luminance mapping: adjustment of the luminance representative of a source signal to the luminance of a targeted
system
post-production: part of the process of filmmaking and video production gathering many different processes such as
video editing, adding visual special effects, transfer of colour motion picture film to video
NOTE: The pre-processed picture is generated during the post-production stage at the encoding site.
pre-processed picture: output picture of SL-HDR pre-processing stage
presentation display: display that the IRD outputs to
reconstructed picture: output picture of SL-HDR post-processing stage
Single Layer High Dynamic Range (SL-HDR) system: system implementing at least one of the parts of the
ETSI TS 103 433 multi-part document [i.8]
source picture: input picture of SL-HDR pre-processing stage
NOTE: Typically an HDR picture coming from post-production facilities.
Standard Colour Gamut (SCG): chromaticity gamut equal to the chromaticity gamut defined by Recommendation
ITU-R BT.709-6 [2]
Standard Dynamic Range (SDR) system: system having a reference reproduction using a luminance range
constrained by Recommendation ITU-R BT.2035 [i.3], section 3.2
NOTE: Typically no more than 10 stops.
Supplemental Enhancement Information (SEI) message: carriage mechanism defined in Recommendation
ITU-T H.264 [4] and Recommendation ITU-T H.265 [5] that is intended to assist in processes related to decoding,
display or other purposes
target picture: picture graded on an SDR mastering display
Wide Colour Gamut (WCG): chromaticity gamut larger than the chromaticity gamut defined by Recommendation
ITU-R BT.709-6 [2]
3.2 Symbols
3.2.1 Arithmetic operators
For the purposes of the present document, the following arithmetic operators apply:
+
Addition
− Subtraction (as a two-argument operator) or negation (as a unary prefix operator)
× Multiplication, including matrix multiplication
y
x Exponentiation. Specifies x to the power of y. In other contexts, such notation is used for
superscripting not intended for interpretation as exponentiation
/ Integer division with truncation of the result toward zero. For example, 7/4 and -7/-4 are truncated
to 1 and -7/4 and 7/-4 are truncated to -1
÷ Used to denote division in mathematical equations where no truncation or rounding is intended
x
Used to denote division in mathematical equations where no truncation or rounding is intended
y
ETSI
11 ETSI TS 103 433-2 V1.1.1 (2018-01)
3.2.2 Mathematical functions
For the purposes of the present document, the following mathematical functions apply:
x , x ≥ 0
⎧
⎨
− x , x < 0
Abs( x ) ⎩
x , z < x
⎧
⎪
Clip3( x; y; z )
y , z > y
⎨
⎪
z , otherwise
⎩
Floor( x ) the largest integer less than or equal to x.ln( x ) natural logarithm of x
log10( x ) the base-10 logarithm of x
x , x ≤ y
⎧
Min( x ; y )
⎨
y , x > y
⎩
x , x ≥ y
⎧
Max( x ; y )
⎨
y , x < y
⎩
x = y.z x takes on integer values starting from y to z, inclusive, with x, y, and z being integer numbers and
z being greater than y
3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
AVC Advanced Video Coding
CE Consumer Electronics
CIE Commission Internationale de l’Eclairage
CRC Cyclic Redundancy Check
EDID Extended Display Identification Data
EOTF Electro-Optical Transfer Function
HDMI High-Definition Multimedia Interface
HDR High Dynamic Range
HEVC High Efficiency Video Coding
IRD Integrated Receiver Decoder
LSB Least Significant Bit
LUT Look-Up Table
MDCV Mastering Display Colour Volume
MSB Most Significant Bit
PQ Perceptual Quantization
RGB Red Green Blue colour model
SCG Standard Colour Gamut
SDRLUT Standard Dynamic Range Look-Up Table
SEI Supplemental Enhancement Information (as in AVC and HEVC)
SL-HDR Single Layer High Dynamic Range
SL-HDRI Single Layer High Dynamic Range Information
SMPTE Society of Motion Picture and Television Engineers
STB Set Top Box
VSVDB Vendor-Specific Video Data Block
WCG Wide Colour Gamut
ETSI
12 ETSI TS 103 433-2 V1.1.1 (2018-01)
3.4 Conventions
Unless otherwise stated, the following convention regarding the notation is used:
• Variables specified in the present document are indicated by bold Arial font 9 points lower camel case style
e.g. camelCase. All those variables are described in clause 6.
• Internal variables of the present document are indicated by italic Cambria math font 10 points style
e.g. variable.
• Structures of syntactic elements or structures of variables are indicated by Arial font 9 points C-style with
parentheses e.g. structure_of_variables( ). Those structures are defined in clause 6 of part 1 [1], Annex A of
part 1 [1], and Annex B of part 1 [1].
• Bitstream syntactic elements are indicated by bold Arial font 9 points C-style e.g. syntactic_element. All
those variables are defined in Annex A of part 1 [1] and in Annex B of part 1 [1].
• Functions are indicated as func( x ).
• Tables are indicated as table[ idx ].
4 End-to-end system
Figure 1 shows an end-to-end workflow supporting content production and delivery to HDR and SDR displays and to
displays with any maximum luminance level in-between SDR and HDR. The primary goal of this HDR workflow is to
provide direct HDR backward compatible services i.e. services which associated streams are directly compatible with
HDR Consumer Electronics devices. This workflow is based on technologies and standards that facilitate an open
approach.
It includes a single-layer HDR encoding-decoding, and uses static and dynamic metadata:
• Mastering Display Colour Volume (MDCV) standardized in AVC [4], HEVC [5] and SMPTE ST 2086 [7]
specifications; and
• SL-HDR Information (SL-HDRI) based on both SMPTE ST 2094-20 [i.6] and SMPTE ST 2094-30 [i.7]
specifications.
Single-layer encoding/decoding requires only one encoder instance at HDR encoding side, and one decoder instance at
player/display side. It supports the real-time workflow requirements of broadcast applications.
The elements specifically addressed in the present document are related to the HDR/SDR reconstruction process and the
associated dynamic metadata format.

Figure 1: Example of an HDR end-to-end system
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13 ETSI TS 103 433-2 V1.1.1 (2018-01)
5 HDR system architecture
The block diagram in Figure 2 depicts in more detail the HDR decomposition and reconstruction processes. The centre
block included in dash-red box corresponds to the distribution encoding and decoding stages (e.g. based on HEVC
video coding specifications). The left and right grey-coloured boxes respectively enable format adaptation to the input
video signal of the HDR system and to the targeted system (e.g. a STB, a connected TV, etc.) connected with the HDR
system. The black solid line boxes show the HDR specific processing. The additional HDR dynamic metadata are
transmitted on distribution networks typically by way of the SEI messaging mechanism. The present document relates
to both the HDR-to-HDR/SDR signal reconstruction process and the HDR metadata format. The core component of the
HDR decomposition stage is the HDR-to-SDR decomposition that generates an SDR video from the HDR signal.
Optionally in the IRD, a block of gamut mapping may be used when the output HDR/SDR picture is represented in a
colour space or colour gamut different from the one of the connected display. The parameters of the optional gamut
mapping and their impact on the rendering may be controlled during the post-production stage.
Optionally in the IRD, a block of HDR-to-HDR signal reconstruction may be used as a display adaptation process. The
dynamic range output of the display adaptation process may be less and may be more than the dynamic range of the
HDR signal input to the HDR-to-SDR signal decomposition process.

Figure 2: HDR system architecture overview
6 Dynamic metadata format for HDR-to-HDR/SDR
adaptation
Clause 6 of ETSI TS 103 433-1 [1] specifies the dynamic metadata format for signal reconstruction. In the present
document, the dynamic metadata allow conversion of the HDR signal to any maximum luminance between SDR
(100 cd/m²) and a value higher than the original maximum luminance, guided by this dynamic metadata. A
recommendation for the maximum luminance boundary can be found in Annex H.
Clause 6 of ETSI TS 103 433-1 [1] shall apply to the present document, taking into account the restrictions on allowed
values and the setting of specific values as specified in Annex A of the present document, as they change clause 6
through the mapping specified in Annex A of ETSI TS 103 433-1 [1] and taking the following exceptions into account.
SL-HDR2 core metadata related clauses:
• Clause 6.2.2 "Signal reconstruction information" of ETSI TS 103 433-1 [1]
In the present document, the reconstructed signal can be an SDR signal, in case the presentation display
adaptation of clause 7.3 is not used in clause 7.2, or an HDR signal if the presentation display adaptation is
used.
• Clause 6.3.2.1 "Introduction" of [1]
In the present document, signal_reconstruction_info contains the dynamic metadata that, when combined with
the associated HDR picture, enables reconstruction of an SDR picture (as described in clause 7), in case the
presentation display adaptation of clause 7.3 is not used in clause 7.2, or an HDR picture if the presentation
display adaptation is used.
• The note in clause 6.3.3.4 "hdrDisplayMaxLuminance - HDR mastering display maximum luminance" of [1]
does not apply to the present document.
ETSI
14 ETSI TS 103 433-2 V1.1.1 (2018-01)
• Clause 6.3.4.1 "Introduction" of [1]
In the present document, the HDR picture and not the SDR picture is intended to be encoded and transmitted
on distribution networks.
• Clause 6.3.5.1, 6.3.6.1, 6.3.7.1, and 6.3.8.1 "Introduction" of [1]
In the present document, those variables are used in the HDR-to-HDR/SDR signal reconstruction process
specified in clause 7.
Gamut Mapping related clauses
• Clause 6.3.2.9 "gamutMappingMode" of [1]
In the present document, the value of gamutMappingMode shall be in the range of 0 to 1, inclusive, and
4 to 5, inclusive, and 64 to 127, inclusive, see Table 2.
Table 2: Gamut mapping mode
Value of gamutMappingMode Gamut mapping mode
0 Implementation dependent method
1 Explicit parameters (see clause 6.3.9 of [1])
2 Reserved for ETSI TS 103 433-1 [1]
3 Reserved for ETSI TS 103 433-1 [1]
4 Preset #3: P3D65 to BT.709 gamut (see Table 3)
5 Preset #4: BT.2020 to BT.709 gamut (see Table 4)
6 - 63 Reserved for future use
64 - 127 Unspecified
128 - 255 Reserved for future use

Preset #3 and preset #4 shall only apply to the present document. In the present document, Table 3 and Table 4
respectively provide the predetermined values of the variables that respectively correspond to a gamut
mapping (gamut compression) from P3D65 gamut represented with BT.2020 primaries to BT.709 gamut
represented with BT.709 primaries (preset #3) or from BT.2020 gamut represented with BT.2020 primaries to
BT.709 gamut represented with BT.709 primaries (preset #4).
Table 3: Preset #3: P3D65 gamut with BT.2020 primaries to BT.709 gamut
Gamut mapping variable Variable value
satMappingMode 2
sat1SegRatio[ c ]
{ ; ; ; ; ; }
sat2SegRatioWCG[ c ]
{ ; ; ; ; ; }
sat2SegRatioSCG[ c ]
{ ; ; ; ; ; }
lightnessMappingMode 2
croppingModeSCG 2
cmCroppedLuminanceMappingEnabledFlag 1
hueAdjMode 1
hueAlignCorrectionPresentFlag 1
hueAlignCorrection[ c ] {4; 5; 4; 4; 5; 4}
chromAdjPresentFlag 0
ETSI
15 ETSI TS 103 433-2 V1.1.1 (2018-01)
Table 4: Preset #4: BT.2020 gamut to BT.709 gamut
Gamut mapping variable Variable value
satMappingMode 2
sat1SegRatio[ c ]
{ ; ; ; ; ; }
sat2SegRatioWCG[ c ]
{ ; ; ; ; ; }
sat2SegRatioSCG[ c ]
{ ; ; ; ; ; }
lightnessMappingMode 2
croppingModeSCG 2
cmCroppedLuminanceMappingEnabledFlag 1
hueAdjMode 2
hueGlobalPreservationRatio 4
hueAlignCorrectionPresentFlag 1
hueAlignCorrection[ c ] {4; 5; 4; 4; 5; 4}
chromAdjPresentFlag 0
7 HDR-to-HDR/SDR signal reconstruction process
7.1 Input streams
The input stream is composed of a decoded PQ, see SMPTE ST 2084 [6], HDR video stream and associated dynamic
metadata that are combined to reconstruct an HDR or an SDR video signal. The dynamic metadata can be conveyed
thanks to two mutually exclusive modes: a parameter-based mode (payloadMode 0) and a table-based mode
(payloadMode 1). Concerning ITU-T or ISO/IEC based video codecs, both payload carriage modes are carried by the
SL-HDR Information SEI message specified in [1], which message is a User Data Registered SEI message. The HDR-
to-HDR/SDR reconstruction process is specified in clause 7.2. The metadata recomputation necessary for the HDR-to-
HDR reconstruction process is specified in clause 7.3. These processes employ syntax element specified in clause 6.2
of [1] and retrieved from parsed and mapped (see clause A.2.3 of [1]) dynamic metadata streams. Semantics attached to
the syntax elements is provided in clause 6.3 of [1].
7.2 Reconstruction process of an SDR or HDR stream
7.2.1 Introduction
Clause 7.2 specifies the reconstruction process enabling the generation of an SDR picture from an HDR picture with
associated dynamic metadata. In this case, the associated dynamic metadata are used unchanged.
Clause 7.2 also specifies the reconstruction process enabling the generation of an HDR picture adapted for the
maximum luminance, , of the presentation display from an HDR picture with associated dynamic metadata. This

case is called display adaptation. In this case, the associated dynamic metadata are recomputed first as specified in
clause 7.3 before they are used as specified in the next clauses of clause 7.2. The value of can be anywhere in

between SDR, 100 cd/m², and a value higher than the maximum luminance of the HDR grading monitor used to grade
the input HDR picture (source picture). See Annex H for the recommended range of values of to perform display

adaptation with. The maximum supported HDR grading monitor luminance is 10 000 cd/m .
This process is defined for a full range PQ HDR picture signal, see SMPTE ST 2084 [6]. For an HDR picture defined as
narrow-range signal, an (unspecified) conversion to full range process shall be applied first (e.g. as specified in
Annex A of SMPTE ST 2084 [6]). The specified process assumes that the HDR picture signal is represented with a bit
depth of 10-bit per component.
ETSI
16 ETSI TS 103 433-2 V1.1.1 (2018-01)
The process depicted in Figure 3 can be summarized as follows:
• From the input metadata conveyed in either payloadMode 0 or 1, a luma-related look-up table, lutMapY, is
derived (see clause 7.2.3.1).
• Similarly, from the input metadata conveyed in either payloadMode 0 or 1, a colour correction look-up table,
lutCC, is derived (see clause 7.2.3.2).
• The next step, described in clause 7.2.4, consists of applying the HDR-to-HDR/SDR reconstruction from the
input HDR picture (source picture), the derived luma-related look-up table and colour correction look-up table.
This process produces an output linear-light HDR or SDR picture.
• An optional gamut mapping can be applied when the colour gamut and/or colour space of the output
HDR/SDR picture (as specified by the variable sdrPicColourSpace) and the one of the connected display are
different. If the optional gamut mapping parameters are present in the dynamic metadata, they may be used for
the optional gamut mapping, see clause A.2.2.3 and clause A.2.2.4 of [1].

Figure 3: Overview of the SDR reconstruction process.
In the next clauses of clause 7.2, the variables picWidth, picHeight and maxSampleVal are defined as follows:
• picWidth and picHeight are the width and height, respectively, of the HDR picture (e.g. as specified by the
syntax elements pic_width_in_luma_samples and pic_height_in_luma_samples in the HEVC
specification [5]);
• maxSampleVal is equal to 2 i.e. 1 024.
When reconstructing an SDR picture, 100 cd/m² shall be used, in the next clauses of clause 7.2 for the value of the
variable , the maximum luminance of the presentation display and the metadata values shall be used unchanged.

When reconstructing an HDR picture with a different maximum luminance than 100 cd/m², the metadata values

have to be recomputed first, as specified in clause 7.3, before they can be used in the next clauses of clause 7.2. The
value of can in this case be anywhere in between SDR, 100 cd/m², and the maximum luminance

hdrDisplayMaxLuminance (see
...