ISO/IEC 39794-16:2021

INTERNATIONAL ISO/IEC
STANDARD 39794-16
First edition
2021-06
Information technology — Extensible
biometric data interchange formats —
Part 16:
Full body image data
Reference number
©
ISO/IEC 2021
© ISO/IEC 2021
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ii © ISO/IEC 2021 – All rights reserved

Contents Page
Foreword .vi
Introduction .vii
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Abbreviated terms .10
5 Conformance .13
6 Modality specific information .13
6.1 Purpose .13
6.2 Digital image encoding .14
6.3 Photographic requirements and recommendations for white light imaging .14
6.3.1 General.14
6.3.2 Contrast and saturation .14
6.3.3 Focus and depth of field .15
6.3.4 Greyscale density .15
6.3.5 Colour .15
6.3.6 Radial distortion of the camera lens .15
6.4 Digital requirements and recommendations for images .16
6.4.1 General.16
6.4.2 Geometry .16
6.4.3 Colour .16
6.4.4 Formatting requirements and recommendations .16
6.5 Recommendations for full body image data systems .16
6.5.1 General.16
6.5.2 Architecture .17
6.5.3 Usability and accessibility .17
6.5.4 Practical applications .17
6.6 Full body imaging technical requirements .18
6.6.1 General.18
6.6.2 Optical distortion . .18
6.6.3 Colour fidelity .18
6.6.4 Example full body photographs .19
6.7 Full body photography session .21
6.7.1 General.21
6.7.2 Typical workflow for full body photography session .21
6.7.3 Full body photograph content requirements .22
6.8 Photo studio recommendations for full body photography .22
6.8.1 General.22
6.8.2 Recommended camera orientation and margins .23
6.8.3 Recommended positioning and distance between camera and subject .23
6.8.4 Recommended focusing settings .24
6.8.5 Recommended white balance settings for white light imaging.24
6.8.6 Recommended backdrop design .24
6.8.7 Example configurations for a photo studio .25
6.8.8 Basic fidelity image test for white light imaging .26
6.9 Non-white light or multispectral imaging .27
6.9.1 General.27
6.9.2 Infrared imaging . . .28
6.9.3 Ultraviolet imaging .29
6.10 Submillimetre imaging .29
6.11 Imaging use cases .30
6.11.1 General.30
© ISO/IEC 2021 – All rights reserved iii

6.11.2 Imaging system baseline use cases .30
7 Abstract data elements .32
7.1 Overview .32
7.1.1 Content and notation .32
7.1.2 Body tree concept .33
7.1.3 Anthropometric data models .36
7.1.4 Structure overview .36
7.1.5 Data conventions .38
7.2 Body image data block .38
7.3 Version block .39
7.4 Representation block .39
7.5 Representation ID.39
7.6 Capture date/time block . .39
7.7 Quality blocks .39
7.8 PAD data block.40
7.9 Session identifier.40
7.10 Derived from .40
7.11 Capture device block .40
7.12 Model identifier block .40
7.13 Certification identifier block .40
7.14 Body part number .41
7.15 Pose angle block .42
7.15.1 Yaw angle, Y .44
7.15.2 Pitch angle, P .44
7.15.3 Roll angle, R .44
7.16 Angle data block .44
7.17 Angle value .44
7.18 Angle uncertainty .44
7.19 Landmark blocks .45
7.20 Landmark kind .45
7.21 MPEG-4 feature point .45
7.22 Eye and nostril centre landmark point .45
7.23 Anthropometric landmark for face and body .45
7.23.1 Anthropometric landmark for face .45
7.23.2 CAESAR anthropometric 3D landmark point .46
7.23.3 MPEG-4 body point .49
7.24 Landmark coordinates block .50
7.25 Image representation block .50
7.26 2D image representation block .51
7.27 2D representation data .51
7.28 2D capture device block .51
7.29 Capture wavelength range block .51
7.30 Capture device technology.53
7.31 2D image information block .54
7.32 2D image kind .54
7.33 Post acquisition processing .55
7.34 Lossy transformation attempts .56
7.35 Image data format .56
7.36 Camera to subject distance (CSD) .57
7.37 Sensor diagonal .57
7.38 Lens focal length .57
7.39 Image size block .57
7.40 Image width .57
7.41 Image height .57
7.42 Sampling rate block .57
7.43 Spatial sampling rate .58
7.44 Temporal sampling rate .58
7.45 Image colour space .58
iv © ISO/IEC 2021 – All rights reserved

7.46 Reference colour mapping block .58
7.47 Reference colour schema .59
7.48 Reference colour definition and value block .59
7.49 JPEG EXIF .59
7.50 Forensic findings block .60
7.50.1 Forensic observations .60
7.50.2 Link to reports .60
7.50.3 Dynamic range low .60
7.50.4 Dynamic range high . . .61
7.50.5 Dynamic range notes .61
7.50.6 Colour fidelity CIELAB a* .61
7.50.7 Colour fidelity CIELAB b* .61
7.50.8 Colour fidelity notes . .62
7.50.9 Image sharpness .62
7.50.10 Image sharpness notes .62
7.51 3D shape representation block .62
8 Encoding .62
8.1 Data encoding models.62
8.2 Tagged binary encoding .65
9 Registered BDB format identifiers .66
Annex A (normative) Formal definitions .67
Annex B (informative) Encoding examples .81
Annex C (normative) Conformance testing methodology .96
Annex D (informative) Application profiles .105
Annex E (informative) Image acquisition measurements .111
Bibliography .137
© ISO/IEC 2021 – All rights reserved v

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are
members of ISO or IEC participate in the development of International Standards through technical
committees established by the respective organization to deal with particular fields of technical
activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international
organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the
work.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for
the different types of document should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives or www .iec .ch/ members
_experts/ refdocs).
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent
rights. Details of any patent rights identified during the development of the document will be in the
Introduction and/or on the ISO list of patent declarations received (see www .iso .org/ patents) or the IEC
list of patent declarations received (see patents.iec.ch).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso .org/
iso/ foreword .html. In the IEC, see www .iec .ch/ understanding -standards.
This document was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 37, Biometrics.
A list of all parts in the ISO/IEC 39794 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html and www .iec .ch/ national
-committees.
The purchase of this ISO/IEC document carries a copyright licence for the purchaser to use ISO/IEC
copyright in the schemas in the annexes to this document for the purpose of developing, implementing,
installing and using software based on those schemas, subject to ISO/IEC licensing conditions set out in
the schemas.
vi © ISO/IEC 2021 – All rights reserved

Introduction
Most countries around the world use biometric recognition systems for law enforcement and border
control. Many of these systems are not limited to face recognition purposes. To be consistent in such
deployments and processes, technical documents, guidelines and best practice recommendations
are being developed by different groups. These documents are primarily focused on the issuance
and use of identity documents and related border control systems, and the technical and operational
issues to be considered when planning and deploying them. "Face" is the biometric mode most suited
to the practicalities of travel documents and automated border processing. "Full body" is a biometric
mode that can be used in addition to face (for example, in border-crossing watchlist scenarios, crime
surveillance, etc.). Full body can also be used in forensic scenarios.
There is very little guidance covering full body imaging for cross-border or law enforcement biometric
recognition purposes. There is a need for guidance for the use of high-quality digital cameras and video
surveillance devices, as well as guidance on full body data interchange structure semantics, syntax and
format for the collection and use of full body image data in biometric recognition scenarios. A specific
extensible biometric data interchange format for cross-border interoperability is required for full body
images. Full body image data standardization is required to ensure threshold quality for database
images for identification and verification using video surveillance and other similar system-generated
images.
Figure 1 illustrates components of a full body image biometric system on a checkered background.
Key
enrolment
verification
identification
NOTE Figure 1 shows the information flow within a general biometric system, showing a general biometric
system consisting of data capture, signal processing, data storage, comparison and decision subsystems. Each of
these subsystems are defined in ISO/IEC 39794-1 in more detail.
Figure 1 — Components of a biometric system
© ISO/IEC 2021 – All rights reserved vii

Border personnel, immigration officials and police officers take full body images using local practices
where no international standards are available to outline the practices which enable cross-border
interoperability. This document can therefore be helpful for the description of the full body biometric
characteristics and associated non-biometric information for identification purposes in disaster victim
and law enforcement scenarios (e.g. victim identification, unknown bodies and missing individuals).
To enable applications on a wide variety of devices, including devices that have limited data storage,
and to improve biometric recognition accuracy, other parts of the ISO/IEC 39794 series address data
format, scene constraints (lighting, pose, expression, etc.), photographic properties (positioning,
camera focus, etc.), and digital image attributes (image resolution, image size, etc.).
In order to fully understand the requirements implied in this document, it is recommended that the
user become acquainted with certain other documents:
— ISO 22311: this document specifies a common output file format that can be extracted from the
video-surveillance contents collection systems to perform necessary processing.
— The ISO/IEC 30137 series: this series specifies the use of biometrics in video surveillance systems.
[22]
— EN 62676 : this document defines video surveillance systems for use in security applications.
This document (ISO/IEC 39794-16) is originally based on CEN/TS 17051.
viii © ISO/IEC 2021 – All rights reserved

INTERNATIONAL STANDARD ISO/IEC 39794-16:2021(E)
Information technology — Extensible biometric data
interchange formats —
Part 16:
Full body image data
1 Scope
This document is intended to provide a generic extensible full body image data format for biometric
recognition applications requiring exchange of human full body image data. Typical applications are:
a) automated body biometric verification and identification of an unknown individual or cadaver
(one-to-one as well as one-to-many comparison);
b) support for human verification of identity by comparison of individuals against full body images;
and
c) support for human examination of full body images with sufficient resolution to allow a human
examiner to verify identity or identify a living individual or a cadaver.
This document ensures that full human body images and image sequence data generated by video
surveillance and other similar systems are suitable for identification and verification.
The structure of the data format in this document is compatible with ISO/IEC 39794-5. In addition
to the data format, this document specifies application-specific profiles including scene constraints,
photographic properties and digital image attributes like image spatial sampling rate, image size, etc.
These application profiles are contained in a series of annexes.
The 3D encoding types "3D point map" and "range image" are not supported by this document.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO/IEC 2382-37, Information technology — Vocabulary — Part 37: Biometrics
ISO/IEC 8824-1, Information technology — Abstract Syntax Notation One (ASN.1) — Part 1: Specification
of basic notation
ISO/IEC 10918-1, Information technology – Digital compression and coding of continuous-tone still images:
Requirements and guidelines
ISO 12052, Health informatics — Digital imaging and communication in medicine (DICOM) including
workflow and data management
ISO 12233, Photography — Electronic still picture imaging — Resolution and spatial frequency responses
ISO/IEC 14496-2:2004, Information technology — Coding of audio-visual objects — Part 2: Visual
ISO/IEC 14496-10, Information technology — Coding of audio-visual objects — Part 10: Advanced video
coding
ISO/IEC 14496-14, Information technology — Coding of audio-visual objects — Part 14: MP4 file format
© ISO/IEC 2021 – All rights reserved 1

ISO/IEC 15444-1, Information technology — JPEG 2000 image coding system — Part 1: Core coding system
ISO/IEC 15444-3, Information technology — JPEG 2000 image coding system: Motion JPEG 2000 — Part 3
ISO/IEC 15948, Information technology — Computer graphics and image processing — Portable Network
Graphics (PNG): Functional specification
ISO/IEC 39794-1, Information technology — Extensible biometric data interchange formats — Part 1:
Framework
ISO/IEC 39794-5, Information technology — Extensible biometric data interchange formats — Part 5:
Face image data
ITU-T Rec. T.81, Information technology — Digital compression and coding of continuous-tone still
images — Requirements and guidelines
ITU-T Rec. T.802, Information technology — JPEG 2000 image coding system: Motion JPEG 2000
XML Schema Part 1: Structures Second Edition, W3C Recommendation, 28 October 2004, http:// www
.w3 .org/ TR/ xmlschema -1/
XML Schema Part 2: Datatypes Second Edition, W3C Recommendation, 28 October 2004, http:// www
.w3 .org/ TR/ xmlschema -2/
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 39794-1 and
ISO/IEC 2382-37 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
2D image
two-dimensional biometric capture subject (3.67) body representation that encodes (3.18) the
luminance and/or colour variations of a biometric capture subject in a given lighting environment or a
set of images recorded using required radiation bandwidths
3.2
3D shape
DEPRECATED 3D image
three-dimensional biometric capture subject (3.67) body representation that encodes (3.18) a surface
or a volumetric shape in a 3D space
3.3
3D point map
3D point cloud representing a biometric capture subject (3.67), where each surface point is encoded
with a triplet, representing the point as coordinate values (3.72) in a 3D Cartesian coordinate system
(3.10) respectively
3.4
4K
UHDTV resolution of 3840 px × 2160 px to achieve a 16 × 9 aspect ratio
Note 1 to entry: UHDTV is an abbreviation for Ultra High Definition Television, defined in documents: SMPTE ST
2036-1 and Recommendation ITU-R BT.2020.
2 © ISO/IEC 2021 – All rights reserved

3.5
anthropometric landmark
landmark point on the biometric capture subject (3.67) representation used for identification and
classification of humans
3.6
artificial intelligence
AI
discipline concerned with the building of computer systems that perform tasks requiring intelligence
when performed by humans
3.7
biometric feature vector
one-dimensional matrix (3.48) representation of biometric features
Note 1 to entry: Feature vector (3.73) is a list of numbers taken from the output of a neural network (3.51) layer
or other biometric process capable of creating a one-dimensional matrix representation of biometric features.
3.8
cadaver
dead body of a human
Note 1 to entry: The definition of "cadaver" does not include the dead body of an animal.
3.9
camera to subject distance
CSD
distance between the eyes or the body surface plane of a capture subject (3.67) and the sensor/image
plane of the camera
Note 1 to entry: In full body images (3.32) body surface plane is used when eyes plane is not visible.
3.10
Cartesian coordinate system
3D orthogonal coordinate system
3.11
CIE standard illuminant D65
commonly used standard illuminant defined by the International Commission on Illumination (CIE)
that is intended to represent average daylight and has a correlated colour temperature of approximately
6 500 K
Note 1 to entry: CIE standard illuminant D65 is specified in ISO/IEC 11664-2.
3.12
colour image
continuous tone image (3.15) that has more than one channel, each of which is coded with one or multiple
bits
3.13
colour space
way of representing colours of pixels in an image
EXAMPLE RGB, YUV and LAB are colour spaces typically used in this document.
3.14
common biometric exchange formats framework
CBEFF
data format specifically for exchanging biometric data that provides for the encompassing of any
biometric type into a standard format
© ISO/IEC 2021 – All rights reserved 3

3.15
continuous-tone image
image whose channels have more than one bit per pixel
Note 1 to entry: An image, such as a photograph, where the grey levels in the image are continuous and not
discrete.
3.16
Digital Imaging and Communications in Medicine
DICOM
standard for the communication and management of medical imaging (3.41) information and related
data
Note 1 to entry: The DICOM Standard facilitates interoperability of medical imaging equipment.
Note 2 to entry: DICOM is defined in ISO 12052.
3.17
deoxyribo nucleic acid
DNA
complex molecule found in virtually every cell in the body that carries genetic information from one
generation to another
3.18
encode
convert information into a coded form
3.19
eye centre
centre of the line connecting the inner and the outer corner of the eye
Note 1 to entry: The eye centres are the feature points (3.25) 12.1 and 12.2 as defined in ISO/IEC 14496-2.
Note 2 to entry: The inner and the outer corner of the eye are defined by ISO/IEC 14496-2. They are the feature
points 3.12 and 3.8 for the right eye, and 3.11 and 3.7 for the left eye.
3.20
eye to mouth distance
EMD
distance between the face centre, M (3.22), and the mouth midpoint
Note 1 to entry: This corresponds to feature point (3.25) 2.3 from ISO/IEC 14496- 2.
3.21
f-stop
ratio of the lens focal length to the diameter of the entrance pupil
3.22
face centre
M
midpoint of the line connecting the two eye centres (3.19)
3.23
face image
electronic image-based representation of the portrait (3.55) of a capture subject (3.67)
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3.24
facial animation parameter
FAP
standard for virtual representation which includes visual speech intelligibility, mood and gesture by
using feature points (3.25)
Note 1 to entry: This standard is specified in ISO/IEC 14496-1 and ISO/IEC 14496-2.
3.25
feature point
reference point in a biometric capture subject (3.67) image as used by feature recognition algorithms
Note 1 to entry: Commonly referred to as a landmark, an example being the position of the eyes.
3.26
far-infrared
FIR
section of infrared band with wavelength (3.74) from 50 μm - 1000 μm
Note 1 to entry: See ISO 20473.
3.27
fisheye
type of distortion where central objects of the image erroneously appear closer than those at the edge
3.28
forensic
related to methods, techniques and processes used to establish conclusions and/or opinions, facts and
findings, which can be used for legal proceedings[SOURCE: ISO 21043-1:2018, 3.14].
3.29
forensic analysis
scientific tests or techniques used in connection with the detection of crime
3.30
Frankfurt Horizon
FH
standard plane for orientation of the head
Note 1 to entry: The Frankfurt Horizon is defined by a line passing through the right tragion (the front of the ear)
and the lowest point of the right eye socket. It can be hard to define, as it is related to the ear position, which can
be covered by hair.
3.31
full body
anatomical structure of an individual that includes any or all of the head, torso and limbs
Note 1 to entry: Full body refers to a living person or a dead body, and/or personal data (3.53) related to this full
body.
3.32
full body image
representation of a data subject (3.67) covering the full body (3.31)
Note 1 to entry: Full body image is not limited to the anatomical structure of the full body as the data subject
refers to any individual person who can be identified, directly or indirectly, via an identifier such as a name, an
ID number, location data, or via factors specific to the person's physical, physiological, genetic, mental, economic,
cultural or social identity.
3.33
gait
subject's (3.67) manner of walking
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3.34
gamma rays
electromagnetic ionizing radiation, emitted by specific radioactive materials
EXAMPLE Cobalt-60 i.e. Co.
Note 1 to entry: Gamma rays shall be used only to make examinations of non-living matter i.e. cadavers (3.8) or
chemical traces.
[SOURCE: ISO 5576:1997, 2.61, modified — EXAMPLE and Note 1 to entry added.]
3.35
gradation
passing by small degrees from one tone or shade, as of colour, to another
3.36
greyscale image
continuous-tone image (3.15) encoded with one luminance channel
Note 1 to entry: For example, if the luminance channel is coded with 8 bits, the greyscale image is also referred to
as a monochrome or black and white image.
3.37
histogram
accurate representation of the distribu
...