ISO 12231:2012

Photography - Electronic still picture imaging - Vocabulary

1 Scope This International Standard defines terms used in electronic still picture imaging. Only terms related to electronic still picture imaging are defined. These terms are relevant to current tasks or are of general interest in electronic still picture imaging.

Photographie — Prises de vue électroniques — Vocabulaire

Fotografija - Elektronsko upodabljanje mirujočih slik - Slovar

Ta evropski standard določa izraze, ki se uporabljajo pri elektronskem upodabljanju mirujočih slik. Vključeni so samo izrazi, ki so povezani z elektronskim upodabljanjem mirujočih slik. Ti izrazi ustrezajo trenutnim nalogam ali so splošnega pomena za elektronsko upodabljanje mirujočih slik.

General Information

• Status: Withdrawn
• Publication Date: 22-Jan-2012
• Withdrawal Date: 22-Jan-2012
• ICS: 01.040.37 - Image technology (Vocabularies)
• ICS: 37.040.10 - Photographic equipment. Projectors
• Technical Committee: ISO/TC 42 - Photography
• Drafting Committee: ISO/TC 42/WG 18 - Electronic still picture imaging
• Current Stage: 9599 - Withdrawal of International Standard
• Start Date: 05-Feb-2021
• Completion Date: 13-Dec-2025
• Ref Project: SIST ISO 12231:2012 - Photography - Electronic still picture imaging - Vocabulary

Relations

• Revised: ISO/TR 12231-2:2022 - Photography - Electronic still picture imaging terminology - Part 2: Other defined terms
• Effective Date: 06-Jun-2022
• Revised: ISO 12231-1:2020 - Photography - Electronic still picture imaging terminology - Part 1: Supplemental vocabulary
• Effective Date: 23-Apr-2020
• Revises: ISO 12231:2005 - Photography - Electronic still picture imaging - Vocabulary
• Effective Date: 28-Feb-2009

Standards Content (Sample)

SLOVENSKI STANDARD
01-julij-2012
1DGRPHãþD
SIST ISO 12231:2011
)RWRJUDILMD(OHNWURQVNRXSRGDEOMDQMHPLUXMRþLKVOLN6ORYDU
Photography - Electronic still picture imaging - Vocabulary
Photographie - Prises de vue électroniques - Vocabulaire
Ta slovenski standard je istoveten z: ISO 12231:2012
ICS:
01.040.37 Slikovna tehnologija (Slovarji) Image technology
(Vocabularies)
37.040.01 Fotografija na splošno Photography in general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

INTERNATIONAL ISO
STANDARD 12231
Third edition
2012-02-01
Photography — Electronic still picture
imaging — Vocabulary
Photographie — Prises de vue électroniques — Vocabulaire
Reference number
©
ISO 2012
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISO’s
member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail [e-mail]
Web www.iso.org
Published in Switzerland
ii © ISO 2012 – All rights reserved

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International
Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 12231 was prepared by Technical Committee ISO/TC 42, Photography.
This third edition cancels and replaces the second edition (ISO 12231:2005), which has been technically revised.
Introduction
Electronic still picture imaging concepts are drawn from traditional photography, electronics, video, and
information technology. In some cases the concepts are redefined to apply to electronic still picture imaging.
For example, unlike traditional photography, measurements cannot be defined in terms of “film” or “sensitized
material”, since images acquired by digital image capture devices are stored electronically and are not
immediately exposed on film. The meaning of shutter and exposure time is also different for digital image
capture devices, because an electronic imaging sensor typically has image acquisition characteristics that are
different from those of film.
This International Standard provides a vocabulary which standardizes the use and meaning of terms associated
with electronic still picture imaging. It is organized alphabetically and follows natural (English) word order
wherever possible. The source documents for most of the definitions provided in this International Standard are
International Standards on electronic still picture imaging developed by ISO/TC 42 and ISO/TC 130.
Where possible, users are advised to verify if a more recent edition of the source document has been published,
which contains an updated version of the term and definition. Future revisions of this International Standard will
include updated terms and definitions consistent with the source documents at the time the revision is prepared.
iv © ISO 2012 – All rights reserved

INTERNATIONAL STANDARD ISO 12231:2012(E)
Photography — Electronic still picture imaging — Vocabulary
1 Scope
This International Standard defines terms used in electronic still picture imaging.
Only terms related to electronic still picture imaging are defined. These terms are relevant to current tasks or
are of general interest in electronic still picture imaging.
2 Normative references
The following referenced documents are indispensable for the application 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 10918-1, Information technology — Digital compression and coding of continuous-tone still images:
Requirements and guidelines
ISO 12232, Photography — Digital still cameras — Determination of exposure index, ISO speed ratings,
standard output sensitivity, and recommended exposure index
ISO 12234-2, Electronic still-picture imaging — Removable memory — Part 2: TIFF/EP image data format
ISO 15739, Photography — Electronic still-picture imaging — Noise measurements
ISO 21550, Photography — Electronic scanners for photographic images — Dynamic range measurements
IEC 61966-2-1, Multimedia systems and equipment — Colour measurement and management — Part 2-1:
Colour management — Default RGB colour space — sRGB
3 Terms and definitions
3.1
absolute colorimetric coordinates
tristimulus values, or other colorimetric coordinates derived from tristimulus values, where the numerical values
correspond to the magnitude of the physical stimulus
EXAMPLE When CIE 1931 standard colour-matching functions are used, the Y-coordinate value corresponds to the
luminance, not the luminance factor (or some scaled value thereof).
[ISO 22028-1:2004, definition 3.1]
3.2
adapted white
colour stimulus that an observer who is adapted to the viewing environment would judge to be perfectly
achromatic and to have a luminance factor of unity; i.e. absolute colorimetric coordinates that an observer
would consider to be a perfect white diffuser
NOTE 1 The adapted white can vary within a scene.
NOTE 2 See also adopted white (3.5).
NOTE 3 This term is also defined in ISO 22028-1 and ISO/TS 22028-3.
[ISO/TS 22028-2:2006, definition 3.1]
3.3
additive RGB colour space
colorimetric colour space having three colour primaries (generally red, green and blue) such that CIE XYZ
tristimulus values can be determined from the RGB colour space values by forming a weighted combination
of the CIE XYZ tristimulus values for the individual colour primaries, where the weights are proportional to the
radiometrically linear colour space values for the corresponding colour primaries
NOTE 1 A simple linear 3x3 matrix transformation can be used to transform between CIE XYZ tristimulus values and
the radiometrically linear colour space values for an additive RGB colour space.
NOTE 2 Additive RGB colour spaces are defined by specifying the CIE chromaticity values for a set of additive RGB
primaries and a colour space white point, together with a colour component transfer function.
NOTE 3 This term is also defined in ISO 22028-1 and ISO/TS 22028-3.
[ISO/TS 22028-2:2006, definition 3.2]
3.4
addressable photoelements
number of active photoelements in an image, which is equal to the number of active lines of photoelements
multiplied by the number of active photoelements per line
NOTE 1 It is possible that the number of addressable photoelements may be different for the different colour records
of an image. When the signal values of the photoelements are digitized, the digitized code values may be referred to as
picture elements, or pixels.
NOTE 2 This term is also defined in ISO 16067-1, ISO 16067-2 and ISO 21550.
[ISO 12233:2000, definition 3.1]
3.5
adopted white
spectral radiance distribution as seen by an image capture or measurement device and converted to colour
signals that are considered to be perfectly achromatic and to have an observer adaptive luminance factor of
unity, i.e. colour signals that are considered to correspond to a perfect white diffuser
NOTE 1 The adopted white can vary within a scene.
NOTE 2 No assumptions can be made concerning the relation between the adapted or adopted white and measurements
of near perfectly reflecting diffusers in a scene, because measurements of such diffusers will depend on the illumination
and viewing geometry, and other elements in the scene that can affect perception. It is easy to arrange conditions for
which a near perfectly reflecting diffuser will appear to be grey or coloured.
NOTE 3 See also adapted white (3.2).
NOTE 4 This term is also defined in ISO 17321-1 and ISO 22028-1.
3.6
album
end-user created object used to logically group data objects according to some user-defined criteria
NOTE An album might or might not be a physical folder in a file system. In this International Standard, an album is a
type of association.
[ISO 15740:2008, definition 3.1]
3.7
aliasing
output image artefacts that occur in a sampled imaging system for input images having significant energy at
frequencies higher than the Nyquist frequency of the system
NOTE 1 These artefacts usually manifest themselves as moiré patterns in repetitive image features or as jagged
“stairstepping” at edge transitions.
2 © ISO 2012 – All rights reserved

NOTE 2 This term is also defined in ISO 12233, ISO 16067-2 and ISO 21550.
[ISO 16067-1:2003, definition 3.2]
3.8
aliasing ratio
value equal to the “maximum minus minimum” modulation divided by the “average” modulation of an electronic
still picture camera when imaging a frequency burst of constant spatial frequency
NOTE The aliasing ratio is described in 6.4 of ISO 12233:2000.
[ISO 12233:2000, definition 3.4]
3.9
application
image application software for use on a personal computer
[ISO 12231:2005, definition 3.5]
3.10
Application Programming Interface
API
high-level functional description of a software interface
NOTE 1 An API is typically language-dependent.
NOTE 2 This was taken from ISO 15740:2005, definition 3.2, which has been cancelled and replaced by ISO 15740:2008.
3.11
artefactual attribute
attribute of image quality that, when evident in an image, nearly always leads to a loss of overall image quality
NOTE The commonly used terms defect and impairment are similar in meaning.
EXAMPLE Examples of artefactual attributes include noise and aliasing.
[ISO 20462-1:2005, definition 3.1, ISO 20462-3:2005, definition 3.1]
3.12 aspect ratio
3.12.1
image aspect ratio
ratio of the image width to the image height
[ISO 12233:2000, definition 3.10, ISO 15740:2008, definition 3.16]
3.12.2
pixel aspect ratio
ratio of the distance between sampling points in the two orthogonal sampling directions
NOTE 1 If the distances are equal, the pixel aspect ratio equals 1:1, and is said to be “square”.
NOTE 2 See also image aspect ratio (3.12.1).
[ISO 12231:2005, definition 2.6.2]
3.13
association
logical construct used to expose a relationship between discrete objects
NOTE Associations are used to indicate that separate data objects are related. Associations are represented like
folders, and may be nested using a standard branched hierarchical tree structure.
EXAMPLE A time sequence or user-defined groupings by content or capture session.
[ISO 15740:2008, definition 3.2]
3.14
attribute
aspect, dimension, or component of overall image quality
NOTE 1 See also artefactual attribute (3.11) and preferential attribute (3.138).
NOTE 2 This term is also defined in ISO 20462-1 and ISO 20462-3.
EXAMPLE Examples of image quality attributes include image structure properties such as sharpness and noise;
colour and tone reproduction properties such as contrast, colour balance, and relative colourfulness; and digital artefacts
such as aliasing, contouring, and compression defects.
3.15
attribute just noticeable difference
attribute JND
measure of the detectability of appearance variations, corresponding to a stimulus difference that would lead
to a 75:25 proportion of responses in a paired comparison task in which univariate stimuli pairs were assessed
in terms of a single attribute identified in the instructions
NOTE 1 As an example, a paired comparison identifying the sharper of two stimuli that differed only in their generating
system modulation transfer function (MTF) would yield results in terms of sharpness attribute JNDs. If the MTF curves
differed monotonically and did not cross, the outcome of the paired comparison would depend primarily upon the observers’
ability to detect changes in the appearance of the stimuli as a function of MTF variations, with little or no value judgement
required of the observers.
NOTE 2 If observers are instead asked to choose which of a pair of stimuli is higher in overall image quality, and if the
stimuli in aggregate are multivariate, such that the observer must make value judgements of the importance of a number
of attributes, rather than focusing on one aspect of image appearance, it is observed experimentally that larger objective
stimulus differences (for example, MTF changes) are required to obtain a 75:25 proportion of responses, which in this case
corresponds to a quality JND.
NOTE 3 A JND is a statistical quantity, derived from a number of observations. An observer assessing a single pair
of images differing by one attribute JND is unlikely to be confident that he or she has detected the sample difference. A
stimulus difference of approximately three JNDs is usually needed for an observer of average sensitivity to feel reasonably
certain of his or her assessment.
NOTE 4 See also quality JND (3.143).
NOTE 5 Adapted from ISO 20462-1.
3.16
categorical sort method
psychophysical method involving the classification of a stimulus into one of several ordered categories, at least some
of which are identified by adjectives or phrases that describe different levels of image quality or attributes thereof
NOTE The application of adjectival descriptors is strongly affected by the range of stimuli presented, so that it is
difficult to compare the results of one categorical sort experiment to another. Range effects and the coarse quantization
of categorical sort experiments also hinder conversion of the responses to JND units. Given these limitations, it is not
possible to unambiguously map adjectival descriptors to JND units, but it is worth noting that in some experiments where
a broad range of stimuli have been presented, the categories excellent, very good, good, fair, poor, and not worth keeping
have been found to provide very roughly comparable intervals that average about six quality JNDs in width.
[ISO 20462-1:2005, definition 3.4, ISO 20462-2:2005, definition 2.5]
3.17
colorimetric colour space
colour space having an exact and simple relationship to CIE colorimetric values
NOTE 1 Colorimetric colour spaces include those defined by CIE (e.g. CIE XYZ, CIELAB, CIELUV, etc.), as well as
colour spaces that are simple transformations of those colour spaces (e.g. additive RGB colour spaces).
NOTE 2 This term is also defined in ISO/TS 22028-2.
[ISO 22028-1:2004, definition 3.5, ISO/TS 22028-3:2006, definition 3.3]
4 © ISO 2012 – All rights reserved

3.18
colour component transfer function
single variable, monotonic mathematical function applied individually to one or more colour channels of
a colour space
NOTE 1 Colour component transfer functions are frequently used to account for the nonlinear response of a reference
device and/or to improve the visual uniformity of a colour space.
NOTE 2 Generally, colour component transfer functions will be nonlinear functions such as a power-law (i.e. “gamma”)
function or a logarithmic function. However, in some cases a linear colour component transfer function may be used.
[ISO 22028-1:2004, definition 3.6, ISO/TS 22028-2:2006, definition 3.4, ISO/TS 22028-3:2006, definition 3.4]
3.19
colour encoding
generic term for a quantized digital encoding of a colour space, encompassing both colour space encodings
and colour image encodings
[ISO 22028-1:2004, definition 3.7, ISO/TS 22028-2:2006, definition 3.5, ISO/TS 22028-3:2006, definition 3.5]
3.20
colour gamut
solid in a colour space, consisting of all those colours that are either: present in a specific scene, artwork,
photograph, photomechanical, or other reproduction; or capable of being created using a particular output
device and/or medium
NOTE See also luminance ratio (3.100).
[ISO 22028-1:2004, definition 3.8, ISO/TS 22028-2:2006, definition 3.6, ISO/TS 22028-3:2006, definition 3.6]
3.21
colour image encoding
digital encoding of the colour values for a digital image, including the specification of a colour space encoding,
together with any information necessary to properly interpret the colour values such as the image state, the
intended image viewing environment and the reference medium
NOTE 1 In some cases the intended image viewing environment will be explicitly defined for the colour image encoding.
In other cases, the intended image viewing environment may be specified on an image-by-image basis using metadata
associated with the digital image.
NOTE 2 Some colour image encodings will indicate particular reference medium characteristics, such as a reflection
print with a specified density range. In other cases the reference medium will not be applicable, such as with a scene-
referred colour image encoding, or will be specified using image metadata.
NOTE 3 Colour image encodings are not limited to pictorial digital images that originate from an original scene, but are
also applicable to digital images with content such as text, line art, vector graphics and other forms of original artwork.
[ISO 22028-1:2004, definition 3.9, ISO/TS 22028-2:2006, definition 3.7, ISO/TS 22028-3:2006, definition 3.7]
3.22
colour matching functions
tristimulus values of monochromatic stimuli of equal radiant power
NOTE See also tristimulus value (3.186).
[CIE Publication 17.4 (845-03-23), ISO 22028-1:2004, definition 3.10]
3.23
colour rendering
mapping of image data representing the colour-space coordinates of the elements of a scene to output-referred
image data representing the colour-space coordinates of the elements of a reproduction
NOTE Colour rendering generally consists of one or more of the following: compensating for differences in the input
and output viewing conditions, tone scale and gamut mapping to map the scene colours onto the dynamic range and
colour gamut of the reproduction, and applying preference adjustments.
[ISO 22028-1:2004, definition 3.11, ISO/TS 22028-2:2006, definition 3.8, ISO/TS 22028-3:2006, definition 3.8]
3.24
colour re-rendering
mapping of picture-referred image data appropriate for one specified real or virtual imaging medium and
viewing conditions to picture-referred image data appropriate for a different real or virtual imaging medium
and/or viewing conditions
NOTE Colour re-rendering generally consists of one or more of the following: compensating for differences in the
viewing conditions, compensating for differences in the dynamic range and/or colour gamut of the imaging media, and
applying preference adjustments.
[ISO 22028-1:2004, definition 3.12]
3.25
colour space
geometric representation of colours in space, usually of three dimensions
[CIE Publication 17.4 (845-03-25), ISO 22028-1:2004, definition 3.13, ISO/TS 22028-2:2006, definition 3.9,
ISO/TS 22028-3:2006, definition 3.9]
3.26
colour space encoding
digital encoding of a colour space, including the specification of a digital encoding method, and a colour
space value range
NOTE 1 Multiple colour space encodings can be defined based on a single colour space where the different colour
space encodings have different digital encoding methods and/or colour space value ranges. (For example, 8-bit sRGB and
10 bit e-sRGB are different colour space encodings based on a particular RGB colour space.)
NOTE 2 This term is also defined in ISO 22028-1, ISO/TS 22028-2 and ISO/TS 22028-3.
3.27
colour space white point
colour stimulus to which colour space values are normalized
NOTE 1 It is not necessary that the colour space white point correspond to the assumed adapted white point and/or the
reference medium white point for a colour image encoding.
NOTE 2 This term is also defined in ISO 22028-1.
[ISO/TS 22028-2:2006, definition 3.11, ISO/TS 22028-3:2006, definition 3.11]
3.28 compression
3.28.1
image compression
process that alters the way digital image data is encoded in order to reduce the size of an image file
[ISO 12233:2000, definition 3.11]
6 © ISO 2012 – All rights reserved

3.28.2
sound compression
process of altering the sound data coding in order to reduce the size of a sound file in the electronic still
picture camera
NOTE See also sound recording (3.167).
[ISO 12234-1:2007, definition 3.8]
3.29
connection
transport-provided mechanism for establishing paths for transferring data between devices
[ISO 15740:2008, definition 3.3]
3.30
continuous colour space values
real-valued, unbounded colour space values that have not been encoded using a digital encoding method
NOTE This term is also defined in ISO 22028-1.
[ISO/TS 22028-2:2006, definition 3.12, ISO/TS 22028-3:2006, definition 3.12]
3.31
cycles per millimetre
cy/mm
unit used for specifying resolution characteristics in terms of the response of an imaging system to a linear
radiance sine wave input, as a function of the frequency of the sine wave
NOTE 1 A range of input sine wave frequencies is obtained in ISO 12233 through the use of a sharp edge target.
NOTE 2 Most pictorial imaging systems exhibit nonlinear behaviour, which can result in the nature of the target affecting
the measured resolution characteristics. Distance units other than millimetres are also used.
NOTE 3 This term is also defined in ISO 12233.
3.32
datacode
16-bit unsigned integer whose Most Significant Nibble (4 bits) is used to indicate the category of code and
whether the code value is standard or vendor-extended
[ISO 15740:2008, definition 3.4]
3.33
dataset
transport-independent collection of one or more individual data items with known interpretations
NOTE Data sets are not necessarily opaque or atomic to transport implementations.
[ISO 15740:2008, definition 3.6]
3.34
data object
image or other type of data that typically exists in persistent storage of a DSPD or other device
[ISO 15740:2008, definition 3.5]
3.35
design rule for camera filesystem
DCF
standard convention for camera filesystems which specifies the file format, foldering and naming conventions
in order to promote file interoperability between conforming digital photography devices
[ISO 15740:2008, definition 3.7]
3.36
device-dependent colour space
colour space defined by the characteristics of a real or idealized imaging device
NOTE Device-dependent colour spaces having a simple functional relationship to CIE colorimetry can also be
categorized as colorimetric colour spaces. For example, additive RGB colour spaces corresponding to real or idealized
CRT displays can be treated as colorimetric colour spaces.
[ISO 22028-1:2004, definition 3.17]
3.37
device discovery
act of determining the set of all devices present on a particular transport or platform that are physically or
logically accessible
[ISO 15740:2008, definition 3.8]
3.38
digital imaging system
system that records and/or produces images using digital data
[ISO 22028-1:2004, definition 3.18, ISO/TS 22028-3:2006, definition 3.13]
3.39
digital output level
digital code value
numerical value assigned to a particular output level
NOTE This term is also defined in ISO 16067-2 and ISO 21550.
[ISO 14524:2009, definition 3.2, ISO 15739:2003, definition 3.2, ISO 16067-1:2003, definition 3.3]
3.40
digital still camera
DSC
device which incorporates an image sensor and produces a digital signal representing a still picture
NOTE 1 A digital still camera is typically a portable, hand-held device. The digital signal is usually recorded on a
removable memory, such as a solid-state memory card or magnetic disk.
NOTE 2 This term is also defined in ISO 12232, ISO 15739 and ISO 17321-1.
3.41
digital print order format
DPOF
standardized ASCII file stored on removable media along with the image files that indicates how many copies
of which images should be printed
NOTE DPOF also allows index prints, cropping, and text overlays to be specified.
[ISO 15740:2008, definition 3.10]
3.42
digital still photography device
DSPD
device with persistent storage that captures a two-dimensional digital still image
[ISO 15740:2008, definition 3.9]
8 © ISO 2012 – All rights reserved

3.43
edge spread function
ESF
normalized spatial signal distribution in the linearized output of an imaging system resulting from imaging a
theoretical infinitely sharp edge
NOTE See also line spread function (3.94), point spread function (3.136).
[ISO 12233:2000, definition 3.5, ISO 16067-1:2003, definition 3.4, ISO 16067-2:2004, definition 3.4,
ISO 21550:2004, definition 3.4]
3.44
effectively spectrally neutral
having spectral characteristics which result in a specific imaging system producing the same output as for a
spectrally neutral object
NOTE 1 See also spectrally neutral (3.169).
NOTE 2 This term is also defined in ISO 21550.
[ISO 12233:2000, definition 3.6, ISO 16067-1:2003, definition 3.5, ISO 16067-2:2004, definition 3.5]
3.45
electronic scanner for photographic films
scanner incorporating an image sensor that outputs a digital signal representing a still film image
NOTE This term is also defined in ISO 21550.
[ISO 16067-2:2004, definition 3.6]
3.46
electronic scanner for photographic prints
scanner incorporating an image sensor that outputs a digital signal representing a still print image
[ISO 16067-1:2003, definition 3.6]
3.47
electromechanical shutter
mechanical shutter which is electronically controlled
[ISO 14524:2009, definition 3.3]
3.48
electronic still-picture camera
camera incorporating an image sensor that outputs an analogue or digital signal representing a still-picture, or
records an analog or digital signal representing a still picture on a removable media, such as a memory card
or magnetic disk
NOTE This term is also defined in ISO 14524 and ISO 15739.
[ISO 12233:2000, definition 3.7]
3.49
enumeration
act of creating an ordered increasing numerical list that contains one representative element for each
member of a set
[ISO 15740:2008, definition 3.11]
3.50
Exif/JPEG
compressed file format for digital cameras in which the images are compressed using the baseline JPEG
standard described in ISO 12234-2
NOTE In Exif, metadata and thumbnail images are stored using TIFF tags within an application segment at the
beginning of the JPEG file.
[ISO 15740:2008, definition 3.12]
3.51
exposure index
EI
numerical value that is inversely proportional to the exposure provided to an image sensor to obtain an image
NOTE Images obtained from a DSC using a range of exposure index values will normally provide a range of image
quality levels.
[ISO 12232:2006, definition 3.2]
3.52
exposure process
various methods to capture images in the electronic still picture camera
3.52.1
single exposure
acquisition of a picture by a single exposure, with one or more image sensors, that exposes all sensor pixels,
all colours, and all image locations at the same time
3.52.2
colour sequential exposure
acquisition of a picture by combining repeated exposures to capture different colour components
NOTE Colour sequential exposure can be by means of three colour illuminations, or by three colour filters.
3.52.3
time sequential exposure
acquisition of a picture by combining repeated exposures to capture different spatial components
NOTE Time sequential exposure can be with a line array (line scanning) or an area array. With a line array, the picture
is acquired by optical or physical sub-scanning with an image sensor in one dimension. With an area array, repeated
exposures may integrate smaller pictures into a larger picture by means of image sensor shifting.
3.53
exposure series
series of images of the same subject taken using different exposure index values
[ISO 12232:2006, definition 3.3]
3.54
extended gamut
colour gamut extending outside that of the standard sRGB CRT display as defined by IEC 61966-2-1
[ISO 22028-1:2004, definition 3.19, ISO/TS 22028-2:2006, definition 3.13, ISO/TS 22028-3:2006, definition 3.14]
3.55
fast scan direction
scan direction corresponding to the direction of the alignment of the addressable photoelements in a linear
array image sensor
[ISO 16067-1:2003, definition 3.7, ISO 16067-2:2004, definition 3.7, ISO 21550:2004, definition 3.7]
10 © ISO 2012 – All rights reserved

3.56
file system
filing system
software structure which specifies how the data are logically organized on a given storage medium
NOTE This term is also defined in ISO 12234-1 and ISO 12234-2.
3.57
film rendering transform
mapping of image data representing measurements of a photographic negative to output-referred image data
representing the colour-space coordinates of the elements of a reproduction
[ISO 22028-1:2004, definition 3.20]
3.58
film unrendering transform
mapping of image data representing measurements of a photographic negative to scene-referred image data
representing estimates of the colour-space coordinates of the elements of the original scene
[ISO 22028-1:2004, definition 3.21]
3.59
flare
light falling on an image, in an imaging system, which does not emanate from the subject point
NOTE 1 Flare is also sometimes referred to as veiling glare.
NOTE 2 See also image flare (3.59.1), veiling flare (3.59.2), veiling glare (3.189).
3.59.1
image flare
light from a subject point that is scattered by the optical system to areas of the image plane other than the
appropriate image point
NOTE The distinction of image-flare light resulting from any subject point is specified by the image point spread
function. Point spread functions tend to fall off rapidly as the distance from the image point is increased, are variable for
different image-point locations and are typically not radially symmetric for image points some distance from the optical
systems axis.
3.59.2
veiling flare
relatively uniform but unwanted irradiation in the image plane of an optical system, caused by the scattering
and reflection of a proportion of the radiation which enters the system through its normal entrance aperture
where the radiation may be from inside or outside the field of view of the system
NOTE Light leaks in an optical system housing can cause additional unwanted irradiation of the image plane. This
irradiation can resemble veiling flare.
[ISO 3664:2009, definition 3.19]
3.60
FlashPix
image file format, defined in FlashPix Format Specification, using a structured storage file containing metadata
and a tiled, hierarchical image representation
NOTE The tiles in a FlashPix image are normally baseline JPEG images, and individual image tiles of a particular
resolution can be easily accessed for rapid display and editing.
[ISO 15740:2008, definition 3.14]
3.61
folder
optional sub-structure in a hierarchical storage area that can contain data objects
[ISO 15740:2008, definition 3.13]
3.62
gamma correction
process that alters the image data in order to modify the tone reproduction
NOTE 1 Gamma correction is performed in part to correct for the nonlinear light-output versus signal input characteristic
of the display. The relationship between the light input level and the output signal level, called the OECF, provides the
gamma correction curveshape for an image capture device.
NOTE 2 The gamma correction is usually an algorithm, lookup table, or circuit which operates separately on each
colour component of an image.
NOTE 3 This term is also defined in ISO 12233, ISO 16067-1, ISO 16067-2 and ISO 21550.
3.63
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 to compensate for differences in the source and output medium colour gamut capability
NOTE The term “gamut mapping” is somewhat more restrictive than the term “colour rendering” because gamut
mapping is performed on colorimetry that has already been adjusted to compensate for viewing condition differences
and viewer preferences, although these processing operations are frequently combined in reproduction and preferred
reproduction models.
[ISO 22028-1:2004, definition 3.22, ISO/TS 22028-2:2006, definition 3.14]
3.64
hardcopy
representation of an image on a substrate which is self-sustaining and reasonably permanent
EXAMPLE Prints, transparencies.
NOTE See also softcopy (3.166).
[ISO 3664:2009, definition 3.4, ISO 22028-1:2004, definition 3.23]
3.65
horizontal resolution
resolution value measured in the longer image dimension, corresponding to the horizontal direction for a
“landscape” image orientation, typically using a vertically oriented test-chart feature
[ISO 12233:2000, definition 3.9]
3.66
ICC profile
International Color Consortium’s file format, used to store transforms from one colour encoding to another, e.g.
from device colour coordinates to profile connection space, as part of a colour management system
[ISO 22028-1:2004, definition 3.24]
3.67
IEEE 1394
high-speed serial bus standardized by the IEEE (Institute of Electrical and Electronics Engineers) currently
having clock rates of 100, 200 and 400 Mbits/sec
NOTE IEEE 1394 is often referred to as FireWire.
[ISO 15740:2008, definition 3.17]
12 © ISO 2012 – All rights reserved

3.68
illuminance scale exposure series
series of exposures produced using a constant exposure time and a varying focal plane illuminance
NOTE See also time scale exposure series (3.181).
[ISO 14524:2009, definition 3.6]
3.69
image capture device
device for converting a scene or a fixed image such as a print, film or transparency, to digital image data
[ISO 15740:2008, definition 3.17]
3.70
image compression
process that alters the way digital image data is encoded in order to reduce the size of an image file
[ISO 12233:2000, definition 3.11]
3.71
image data format
structure and content which specify image and the organization of the image related data in a device
independent manner
NOTE This term is also defined in ISO 12234-2.
[ISO 12234-1:2007, definition 3.2]
3.72
image output device
device that can render a digital image to hardcopy or softcopy media
[ISO 15740:2008, definition 3.18]
3.73
image quality
impression of the overall merit or excellence of an image, as perceived by an observer neither associated with
the act of photography, nor closely involved with the subject matter depicted
NOTE The purpose of defining image quality in terms of third-party (uninvolved) observers is to eliminate sources of
variability that arise from more idiosyncratic aspects of image perception and pertain to attributes outside the control of
imaging system designers.
[ISO 20462-1:2005, definition 3.5, ISO 20462-3:2005, definition 3.3]
3.74
image sensor
electronic device that converts an optical image into an electronic signal; for example a charge coupled
device (CCD) array
NOTE This term is also defined in ISO 12232, ISO 15739, ISO 16067-1, ISO 16067-2 and ISO 21550.
[ISO 12233:2000, definition 3.12]
3.75
image state
attribute of a colour image encoding indicating the rendering state of the image data
NOTE The primary image states defined in this document are the scene-referred image state, the original-referred
image state and the output-referred image state.
[ISO 22028-1:2004, definition 3.25, ISO/TS 22028-2:2006, definition 3.16, ISO/TS 22028-3:2006, definition 3.15]
3.76
image storage application profile
ISAP
media profile, the filing system and the image data format
NOTE The ISAP specifies all the information necessary to completely implement the removable memory.
[ISO 12234-1:2007, definition 3.3]
3.77
in-band event
event transmitted on the same logical connection as operations and responses
NOTE Events are only asynchronous to the degree of data precision for which the transport implementation allows
event interleaving.
[ISO 15740:2008, definition 3.19]
3.78
incremental gain function
change in the output level (digital code value) divided by the change in the input level (luminance or exposure)
as a function of input level
NOTE 1 For the determination of incremental gain values, log input values are not used.
NOTE 2 If the input exposure points are very finely spaced and the output noise is small compared to the quantization
interval, the incremental gain function may have a jagged shape. Such behaviour is an artefact of the quantization process
and should be removed by using an appropriate smoothing algorithm, or by fitting a smooth curve to the data. In some
cases, it may be desirable to fit a curve to the input-output data and then determine the incremental gain function by taking
the first derivative of the function used for the curve fit.
NOTE 3 This term is also defined in ISO 15739 and ISO 21550.
[ISO 14524:2009, definition 3.7]
3.79
incremental output signal
input level (luminance or exposure, not logged) multiplied by the system incremental gain at that level
NOTE 1 See also incremental gain function (3.78).
NOTE 2 This term is also defined in ISO 21550.
[ISO 14524:2009, definition 3.8, ISO 15739:2003, definition 3.7]
3.80
incremental signal to noise ratio
ratio of the incremental output signal to the root mean square (rms) noise level, at a particular signal level
NOTE 1 The incremental signal to noise ratio is typically expressed as a graph or table showing the rms noise level
versus output signal level for the full range of output signal levels.
NOTE 2 This term is also defined in ISO 15739 and ISO 21550.
3.81
Infrared Data Association
IrDA
infrared wireless communication system that currently supports wireless communication at data rates between
9600 bps and 4 Mbps
[ISO 15740:2008, definition 3.22]
14 © ISO 2012 – All rights reserved

3.82
initiator
device that initiates a conversation by opening a session, and issues all formal operations to the responder
NOTE The initiator is analogous to the client in the client/server paradigm.
[ISO 15740:2008, definition 3.20]
3.83
instructions
set of directions given to the observer for performing the psychophysical evaluation task
[ISO 20462-1:2005, definition 3.6, ISO 20462-3:2005, definition 3.4]
3.84
International Color Consortium profile connection space (ICC PCS)
standard colour image encoding defined by the International Color Consortium providing a standard connection
point for combining ICC profiles
NOTE The ICC.1:2001 specification defines two variations of the PCS, an original-referred variation for colorimetric
intent profiles, and a standard output-referred variation for perceptual intent profiles.
[ISO 22028-1:2004, definition 3.26]
3.85
International Imaging Industry Association
I3A
organization that serves to represent the common interests among manufacturers of imaging technology products
NOTE See http://www.i3a.org.
[ISO 15740:2008, definition 3.21]
3.86
ISO DSC dynamic range
ratio of the maximum luminance level that appears unclipped to the minimum luminance level that can be
reproduced with an incremental signal-to-temporal-noise ratio of at least 1, as determined according to ISO 15739
[ISO 15739:2003, definition 3.9]
3.87
ISO scanner dynamic range
difference of the maximum density where the incremental gain is higher than 0,5, as determined according to
ISO 21550, and the minimum density that appears unclipped
[ISO 21550:2004, definition 3.13]
3.88
ISO speed
numerical value calculated from the exposure provided at the focal plane of a DSC to produce specified
camera output signal characteristics using the methods described in ISO 12232
NOTE 1 The ISO speed is usually the highest exposure index value that still provides peak image quality for normal
scenes. However, a DSC does not necessarily use the ISO speed value as the exposure index value when capturing images.
NOTE 2 This term is also defined in ISO 12232.
3.89
ISO speed latitude
set of two numerical values calculated from the exposure provided at the focal plane of an electronic camera to
produce specified camera output signal characteristics using the methods described in ISO 12232
NOTE 1 The ISO speed latitude is expected to correlate with the range of exposure index values that provide acceptable
image quality for normal scenes.
NOTE 2 This term is also defined in ISO 12232.
3.90
Joint Photographic Experts Group
JPEG
specific image compression method defined in ISO/IEC 10918-1
[ISO 15740:2008, definition 3.23]
3.91
just noticeable difference
JND
stimulus difference that leads to a 75:25 proportion of responses in a paired comparison task
NOTE 1 See also attribute JND (3.15) and quality JND (3.143).
NOTE 2 This term is also defined in ISO 20462-3.
[ISO 20462-1:2005, definition 3.7]
3.92
limiting resolution
value of that portion of a specified resolution test pattern, measured in line widths per picture height, which
corresponds to an average modulation value equal to some specified percentage of the modulation value at a
specified reference frequency
EXAMPLE The limiting resolution could be the test pattern value, in line widths per picture height (LW/PH), corresponding
to a camera output modulation level of 5 % of the camera output modulation level at a reference frequency of 10 LW/PH.
NOTE This term is also defined in ISO 12233.
3.93
line pairs per millimetre
lp/mm
metric for specifying resolution in terms of the number of equal width black and white line pairs per millimetre
that can be resolved according to some criterion, such as visual resolution or limiting resolution
NOTE 1 Distance units other than millimetres can also be used.
NOTE 2 This term is also defined in ISO 12233.
3.94
line spread function
LSF
normalized spatial signal distribution in the linearized output of an imaging system resulting from imaging a
theoretical infinitely thin line
NOTE If the imaging system is operating in an isoplanatic region and in its linear range, the LSF is equal to the first
derivative of the ESF.
[ISO 12233:2000, definition 3.16]
16 © ISO 2012 – All rights reserved

---------------------
...

INTERNATIONAL ISO
STANDARD 12231
Third edition
2012-02-01
Photography — Electronic still picture
imaging — Vocabulary
Photographie — Prises de vue électroniques — Vocabulaire
Reference number
©
ISO 2012
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISO’s
member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail [e-mail]
Web www.iso.org
Published in Switzerland
ii © ISO 2012 – All rights reserved

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International
Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 12231 was prepared by Technical Committee ISO/TC 42, Photography.
This third edition cancels and replaces the second edition (ISO 12231:2005), which has been technically revised.
Introduction
Electronic still picture imaging concepts are drawn from traditional photography, electronics, video, and
information technology. In some cases the concepts are redefined to apply to electronic still picture imaging.
For example, unlike traditional photography, measurements cannot be defined in terms of “film” or “sensitized
material”, since images acquired by digital image capture devices are stored electronically and are not
immediately exposed on film. The meaning of shutter and exposure time is also different for digital image
capture devices, because an electronic imaging sensor typically has image acquisition characteristics that are
different from those of film.
This International Standard provides a vocabulary which standardizes the use and meaning of terms associated
with electronic still picture imaging. It is organized alphabetically and follows natural (English) word order
wherever possible. The source documents for most of the definitions provided in this International Standard are
International Standards on electronic still picture imaging developed by ISO/TC 42 and ISO/TC 130.
Where possible, users are advised to verify if a more recent edition of the source document has been published,
which contains an updated version of the term and definition. Future revisions of this International Standard will
include updated terms and definitions consistent with the source documents at the time the revision is prepared.
iv © ISO 2012 – All rights reserved

INTERNATIONAL STANDARD ISO 12231:2012(E)
Photography — Electronic still picture imaging — Vocabulary
1 Scope
This International Standard defines terms used in electronic still picture imaging.
Only terms related to electronic still picture imaging are defined. These terms are relevant to current tasks or
are of general interest in electronic still picture imaging.
2 Normative references
The following referenced documents are indispensable for the application 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 10918-1, Information technology — Digital compression and coding of continuous-tone still images:
Requirements and guidelines
ISO 12232, Photography — Digital still cameras — Determination of exposure index, ISO speed ratings,
standard output sensitivity, and recommended exposure index
ISO 12234-2, Electronic still-picture imaging — Removable memory — Part 2: TIFF/EP image data format
ISO 15739, Photography — Electronic still-picture imaging — Noise measurements
ISO 21550, Photography — Electronic scanners for photographic images — Dynamic range measurements
IEC 61966-2-1, Multimedia systems and equipment — Colour measurement and management — Part 2-1:
Colour management — Default RGB colour space — sRGB
3 Terms and definitions
3.1
absolute colorimetric coordinates
tristimulus values, or other colorimetric coordinates derived from tristimulus values, where the numerical values
correspond to the magnitude of the physical stimulus
EXAMPLE When CIE 1931 standard colour-matching functions are used, the Y-coordinate value corresponds to the
luminance, not the luminance factor (or some scaled value thereof).
[ISO 22028-1:2004, definition 3.1]
3.2
adapted white
colour stimulus that an observer who is adapted to the viewing environment would judge to be perfectly
achromatic and to have a luminance factor of unity; i.e. absolute colorimetric coordinates that an observer
would consider to be a perfect white diffuser
NOTE 1 The adapted white can vary within a scene.
NOTE 2 See also adopted white (3.5).
NOTE 3 This term is also defined in ISO 22028-1 and ISO/TS 22028-3.
[ISO/TS 22028-2:2006, definition 3.1]
3.3
additive RGB colour space
colorimetric colour space having three colour primaries (generally red, green and blue) such that CIE XYZ
tristimulus values can be determined from the RGB colour space values by forming a weighted combination
of the CIE XYZ tristimulus values for the individual colour primaries, where the weights are proportional to the
radiometrically linear colour space values for the corresponding colour primaries
NOTE 1 A simple linear 3x3 matrix transformation can be used to transform between CIE XYZ tristimulus values and
the radiometrically linear colour space values for an additive RGB colour space.
NOTE 2 Additive RGB colour spaces are defined by specifying the CIE chromaticity values for a set of additive RGB
primaries and a colour space white point, together with a colour component transfer function.
NOTE 3 This term is also defined in ISO 22028-1 and ISO/TS 22028-3.
[ISO/TS 22028-2:2006, definition 3.2]
3.4
addressable photoelements
number of active photoelements in an image, which is equal to the number of active lines of photoelements
multiplied by the number of active photoelements per line
NOTE 1 It is possible that the number of addressable photoelements may be different for the different colour records
of an image. When the signal values of the photoelements are digitized, the digitized code values may be referred to as
picture elements, or pixels.
NOTE 2 This term is also defined in ISO 16067-1, ISO 16067-2 and ISO 21550.
[ISO 12233:2000, definition 3.1]
3.5
adopted white
spectral radiance distribution as seen by an image capture or measurement device and converted to colour
signals that are considered to be perfectly achromatic and to have an observer adaptive luminance factor of
unity, i.e. colour signals that are considered to correspond to a perfect white diffuser
NOTE 1 The adopted white can vary within a scene.
NOTE 2 No assumptions can be made concerning the relation between the adapted or adopted white and measurements
of near perfectly reflecting diffusers in a scene, because measurements of such diffusers will depend on the illumination
and viewing geometry, and other elements in the scene that can affect perception. It is easy to arrange conditions for
which a near perfectly reflecting diffuser will appear to be grey or coloured.
NOTE 3 See also adapted white (3.2).
NOTE 4 This term is also defined in ISO 17321-1 and ISO 22028-1.
3.6
album
end-user created object used to logically group data objects according to some user-defined criteria
NOTE An album might or might not be a physical folder in a file system. In this International Standard, an album is a
type of association.
[ISO 15740:2008, definition 3.1]
3.7
aliasing
output image artefacts that occur in a sampled imaging system for input images having significant energy at
frequencies higher than the Nyquist frequency of the system
NOTE 1 These artefacts usually manifest themselves as moiré patterns in repetitive image features or as jagged
“stairstepping” at edge transitions.
2 © ISO 2012 – All rights reserved

NOTE 2 This term is also defined in ISO 12233, ISO 16067-2 and ISO 21550.
[ISO 16067-1:2003, definition 3.2]
3.8
aliasing ratio
value equal to the “maximum minus minimum” modulation divided by the “average” modulation of an electronic
still picture camera when imaging a frequency burst of constant spatial frequency
NOTE The aliasing ratio is described in 6.4 of ISO 12233:2000.
[ISO 12233:2000, definition 3.4]
3.9
application
image application software for use on a personal computer
[ISO 12231:2005, definition 3.5]
3.10
Application Programming Interface
API
high-level functional description of a software interface
NOTE 1 An API is typically language-dependent.
NOTE 2 This was taken from ISO 15740:2005, definition 3.2, which has been cancelled and replaced by ISO 15740:2008.
3.11
artefactual attribute
attribute of image quality that, when evident in an image, nearly always leads to a loss of overall image quality
NOTE The commonly used terms defect and impairment are similar in meaning.
EXAMPLE Examples of artefactual attributes include noise and aliasing.
[ISO 20462-1:2005, definition 3.1, ISO 20462-3:2005, definition 3.1]
3.12 aspect ratio
3.12.1
image aspect ratio
ratio of the image width to the image height
[ISO 12233:2000, definition 3.10, ISO 15740:2008, definition 3.16]
3.12.2
pixel aspect ratio
ratio of the distance between sampling points in the two orthogonal sampling directions
NOTE 1 If the distances are equal, the pixel aspect ratio equals 1:1, and is said to be “square”.
NOTE 2 See also image aspect ratio (3.12.1).
[ISO 12231:2005, definition 2.6.2]
3.13
association
logical construct used to expose a relationship between discrete objects
NOTE Associations are used to indicate that separate data objects are related. Associations are represented like
folders, and may be nested using a standard branched hierarchical tree structure.
EXAMPLE A time sequence or user-defined groupings by content or capture session.
[ISO 15740:2008, definition 3.2]
3.14
attribute
aspect, dimension, or component of overall image quality
NOTE 1 See also artefactual attribute (3.11) and preferential attribute (3.138).
NOTE 2 This term is also defined in ISO 20462-1 and ISO 20462-3.
EXAMPLE Examples of image quality attributes include image structure properties such as sharpness and noise;
colour and tone reproduction properties such as contrast, colour balance, and relative colourfulness; and digital artefacts
such as aliasing, contouring, and compression defects.
3.15
attribute just noticeable difference
attribute JND
measure of the detectability of appearance variations, corresponding to a stimulus difference that would lead
to a 75:25 proportion of responses in a paired comparison task in which univariate stimuli pairs were assessed
in terms of a single attribute identified in the instructions
NOTE 1 As an example, a paired comparison identifying the sharper of two stimuli that differed only in their generating
system modulation transfer function (MTF) would yield results in terms of sharpness attribute JNDs. If the MTF curves
differed monotonically and did not cross, the outcome of the paired comparison would depend primarily upon the observers’
ability to detect changes in the appearance of the stimuli as a function of MTF variations, with little or no value judgement
required of the observers.
NOTE 2 If observers are instead asked to choose which of a pair of stimuli is higher in overall image quality, and if the
stimuli in aggregate are multivariate, such that the observer must make value judgements of the importance of a number
of attributes, rather than focusing on one aspect of image appearance, it is observed experimentally that larger objective
stimulus differences (for example, MTF changes) are required to obtain a 75:25 proportion of responses, which in this case
corresponds to a quality JND.
NOTE 3 A JND is a statistical quantity, derived from a number of observations. An observer assessing a single pair
of images differing by one attribute JND is unlikely to be confident that he or she has detected the sample difference. A
stimulus difference of approximately three JNDs is usually needed for an observer of average sensitivity to feel reasonably
certain of his or her assessment.
NOTE 4 See also quality JND (3.143).
NOTE 5 Adapted from ISO 20462-1.
3.16
categorical sort method
psychophysical method involving the classification of a stimulus into one of several ordered categories, at least some
of which are identified by adjectives or phrases that describe different levels of image quality or attributes thereof
NOTE The application of adjectival descriptors is strongly affected by the range of stimuli presented, so that it is
difficult to compare the results of one categorical sort experiment to another. Range effects and the coarse quantization
of categorical sort experiments also hinder conversion of the responses to JND units. Given these limitations, it is not
possible to unambiguously map adjectival descriptors to JND units, but it is worth noting that in some experiments where
a broad range of stimuli have been presented, the categories excellent, very good, good, fair, poor, and not worth keeping
have been found to provide very roughly comparable intervals that average about six quality JNDs in width.
[ISO 20462-1:2005, definition 3.4, ISO 20462-2:2005, definition 2.5]
3.17
colorimetric colour space
colour space having an exact and simple relationship to CIE colorimetric values
NOTE 1 Colorimetric colour spaces include those defined by CIE (e.g. CIE XYZ, CIELAB, CIELUV, etc.), as well as
colour spaces that are simple transformations of those colour spaces (e.g. additive RGB colour spaces).
NOTE 2 This term is also defined in ISO/TS 22028-2.
[ISO 22028-1:2004, definition 3.5, ISO/TS 22028-3:2006, definition 3.3]
4 © ISO 2012 – All rights reserved

3.18
colour component transfer function
single variable, monotonic mathematical function applied individually to one or more colour channels of
a colour space
NOTE 1 Colour component transfer functions are frequently used to account for the nonlinear response of a reference
device and/or to improve the visual uniformity of a colour space.
NOTE 2 Generally, colour component transfer functions will be nonlinear functions such as a power-law (i.e. “gamma”)
function or a logarithmic function. However, in some cases a linear colour component transfer function may be used.
[ISO 22028-1:2004, definition 3.6, ISO/TS 22028-2:2006, definition 3.4, ISO/TS 22028-3:2006, definition 3.4]
3.19
colour encoding
generic term for a quantized digital encoding of a colour space, encompassing both colour space encodings
and colour image encodings
[ISO 22028-1:2004, definition 3.7, ISO/TS 22028-2:2006, definition 3.5, ISO/TS 22028-3:2006, definition 3.5]
3.20
colour gamut
solid in a colour space, consisting of all those colours that are either: present in a specific scene, artwork,
photograph, photomechanical, or other reproduction; or capable of being created using a particular output
device and/or medium
NOTE See also luminance ratio (3.100).
[ISO 22028-1:2004, definition 3.8, ISO/TS 22028-2:2006, definition 3.6, ISO/TS 22028-3:2006, definition 3.6]
3.21
colour image encoding
digital encoding of the colour values for a digital image, including the specification of a colour space encoding,
together with any information necessary to properly interpret the colour values such as the image state, the
intended image viewing environment and the reference medium
NOTE 1 In some cases the intended image viewing environment will be explicitly defined for the colour image encoding.
In other cases, the intended image viewing environment may be specified on an image-by-image basis using metadata
associated with the digital image.
NOTE 2 Some colour image encodings will indicate particular reference medium characteristics, such as a reflection
print with a specified density range. In other cases the reference medium will not be applicable, such as with a scene-
referred colour image encoding, or will be specified using image metadata.
NOTE 3 Colour image encodings are not limited to pictorial digital images that originate from an original scene, but are
also applicable to digital images with content such as text, line art, vector graphics and other forms of original artwork.
[ISO 22028-1:2004, definition 3.9, ISO/TS 22028-2:2006, definition 3.7, ISO/TS 22028-3:2006, definition 3.7]
3.22
colour matching functions
tristimulus values of monochromatic stimuli of equal radiant power
NOTE See also tristimulus value (3.186).
[CIE Publication 17.4 (845-03-23), ISO 22028-1:2004, definition 3.10]
3.23
colour rendering
mapping of image data representing the colour-space coordinates of the elements of a scene to output-referred
image data representing the colour-space coordinates of the elements of a reproduction
NOTE Colour rendering generally consists of one or more of the following: compensating for differences in the input
and output viewing conditions, tone scale and gamut mapping to map the scene colours onto the dynamic range and
colour gamut of the reproduction, and applying preference adjustments.
[ISO 22028-1:2004, definition 3.11, ISO/TS 22028-2:2006, definition 3.8, ISO/TS 22028-3:2006, definition 3.8]
3.24
colour re-rendering
mapping of picture-referred image data appropriate for one specified real or virtual imaging medium and
viewing conditions to picture-referred image data appropriate for a different real or virtual imaging medium
and/or viewing conditions
NOTE Colour re-rendering generally consists of one or more of the following: compensating for differences in the
viewing conditions, compensating for differences in the dynamic range and/or colour gamut of the imaging media, and
applying preference adjustments.
[ISO 22028-1:2004, definition 3.12]
3.25
colour space
geometric representation of colours in space, usually of three dimensions
[CIE Publication 17.4 (845-03-25), ISO 22028-1:2004, definition 3.13, ISO/TS 22028-2:2006, definition 3.9,
ISO/TS 22028-3:2006, definition 3.9]
3.26
colour space encoding
digital encoding of a colour space, including the specification of a digital encoding method, and a colour
space value range
NOTE 1 Multiple colour space encodings can be defined based on a single colour space where the different colour
space encodings have different digital encoding methods and/or colour space value ranges. (For example, 8-bit sRGB and
10 bit e-sRGB are different colour space encodings based on a particular RGB colour space.)
NOTE 2 This term is also defined in ISO 22028-1, ISO/TS 22028-2 and ISO/TS 22028-3.
3.27
colour space white point
colour stimulus to which colour space values are normalized
NOTE 1 It is not necessary that the colour space white point correspond to the assumed adapted white point and/or the
reference medium white point for a colour image encoding.
NOTE 2 This term is also defined in ISO 22028-1.
[ISO/TS 22028-2:2006, definition 3.11, ISO/TS 22028-3:2006, definition 3.11]
3.28 compression
3.28.1
image compression
process that alters the way digital image data is encoded in order to reduce the size of an image file
[ISO 12233:2000, definition 3.11]
6 © ISO 2012 – All rights reserved

3.28.2
sound compression
process of altering the sound data coding in order to reduce the size of a sound file in the electronic still
picture camera
NOTE See also sound recording (3.167).
[ISO 12234-1:2007, definition 3.8]
3.29
connection
transport-provided mechanism for establishing paths for transferring data between devices
[ISO 15740:2008, definition 3.3]
3.30
continuous colour space values
real-valued, unbounded colour space values that have not been encoded using a digital encoding method
NOTE This term is also defined in ISO 22028-1.
[ISO/TS 22028-2:2006, definition 3.12, ISO/TS 22028-3:2006, definition 3.12]
3.31
cycles per millimetre
cy/mm
unit used for specifying resolution characteristics in terms of the response of an imaging system to a linear
radiance sine wave input, as a function of the frequency of the sine wave
NOTE 1 A range of input sine wave frequencies is obtained in ISO 12233 through the use of a sharp edge target.
NOTE 2 Most pictorial imaging systems exhibit nonlinear behaviour, which can result in the nature of the target affecting
the measured resolution characteristics. Distance units other than millimetres are also used.
NOTE 3 This term is also defined in ISO 12233.
3.32
datacode
16-bit unsigned integer whose Most Significant Nibble (4 bits) is used to indicate the category of code and
whether the code value is standard or vendor-extended
[ISO 15740:2008, definition 3.4]
3.33
dataset
transport-independent collection of one or more individual data items with known interpretations
NOTE Data sets are not necessarily opaque or atomic to transport implementations.
[ISO 15740:2008, definition 3.6]
3.34
data object
image or other type of data that typically exists in persistent storage of a DSPD or other device
[ISO 15740:2008, definition 3.5]
3.35
design rule for camera filesystem
DCF
standard convention for camera filesystems which specifies the file format, foldering and naming conventions
in order to promote file interoperability between conforming digital photography devices
[ISO 15740:2008, definition 3.7]
3.36
device-dependent colour space
colour space defined by the characteristics of a real or idealized imaging device
NOTE Device-dependent colour spaces having a simple functional relationship to CIE colorimetry can also be
categorized as colorimetric colour spaces. For example, additive RGB colour spaces corresponding to real or idealized
CRT displays can be treated as colorimetric colour spaces.
[ISO 22028-1:2004, definition 3.17]
3.37
device discovery
act of determining the set of all devices present on a particular transport or platform that are physically or
logically accessible
[ISO 15740:2008, definition 3.8]
3.38
digital imaging system
system that records and/or produces images using digital data
[ISO 22028-1:2004, definition 3.18, ISO/TS 22028-3:2006, definition 3.13]
3.39
digital output level
digital code value
numerical value assigned to a particular output level
NOTE This term is also defined in ISO 16067-2 and ISO 21550.
[ISO 14524:2009, definition 3.2, ISO 15739:2003, definition 3.2, ISO 16067-1:2003, definition 3.3]
3.40
digital still camera
DSC
device which incorporates an image sensor and produces a digital signal representing a still picture
NOTE 1 A digital still camera is typically a portable, hand-held device. The digital signal is usually recorded on a
removable memory, such as a solid-state memory card or magnetic disk.
NOTE 2 This term is also defined in ISO 12232, ISO 15739 and ISO 17321-1.
3.41
digital print order format
DPOF
standardized ASCII file stored on removable media along with the image files that indicates how many copies
of which images should be printed
NOTE DPOF also allows index prints, cropping, and text overlays to be specified.
[ISO 15740:2008, definition 3.10]
3.42
digital still photography device
DSPD
device with persistent storage that captures a two-dimensional digital still image
[ISO 15740:2008, definition 3.9]
8 © ISO 2012 – All rights reserved

3.43
edge spread function
ESF
normalized spatial signal distribution in the linearized output of an imaging system resulting from imaging a
theoretical infinitely sharp edge
NOTE See also line spread function (3.94), point spread function (3.136).
[ISO 12233:2000, definition 3.5, ISO 16067-1:2003, definition 3.4, ISO 16067-2:2004, definition 3.4,
ISO 21550:2004, definition 3.4]
3.44
effectively spectrally neutral
having spectral characteristics which result in a specific imaging system producing the same output as for a
spectrally neutral object
NOTE 1 See also spectrally neutral (3.169).
NOTE 2 This term is also defined in ISO 21550.
[ISO 12233:2000, definition 3.6, ISO 16067-1:2003, definition 3.5, ISO 16067-2:2004, definition 3.5]
3.45
electronic scanner for photographic films
scanner incorporating an image sensor that outputs a digital signal representing a still film image
NOTE This term is also defined in ISO 21550.
[ISO 16067-2:2004, definition 3.6]
3.46
electronic scanner for photographic prints
scanner incorporating an image sensor that outputs a digital signal representing a still print image
[ISO 16067-1:2003, definition 3.6]
3.47
electromechanical shutter
mechanical shutter which is electronically controlled
[ISO 14524:2009, definition 3.3]
3.48
electronic still-picture camera
camera incorporating an image sensor that outputs an analogue or digital signal representing a still-picture, or
records an analog or digital signal representing a still picture on a removable media, such as a memory card
or magnetic disk
NOTE This term is also defined in ISO 14524 and ISO 15739.
[ISO 12233:2000, definition 3.7]
3.49
enumeration
act of creating an ordered increasing numerical list that contains one representative element for each
member of a set
[ISO 15740:2008, definition 3.11]
3.50
Exif/JPEG
compressed file format for digital cameras in which the images are compressed using the baseline JPEG
standard described in ISO 12234-2
NOTE In Exif, metadata and thumbnail images are stored using TIFF tags within an application segment at the
beginning of the JPEG file.
[ISO 15740:2008, definition 3.12]
3.51
exposure index
EI
numerical value that is inversely proportional to the exposure provided to an image sensor to obtain an image
NOTE Images obtained from a DSC using a range of exposure index values will normally provide a range of image
quality levels.
[ISO 12232:2006, definition 3.2]
3.52
exposure process
various methods to capture images in the electronic still picture camera
3.52.1
single exposure
acquisition of a picture by a single exposure, with one or more image sensors, that exposes all sensor pixels,
all colours, and all image locations at the same time
3.52.2
colour sequential exposure
acquisition of a picture by combining repeated exposures to capture different colour components
NOTE Colour sequential exposure can be by means of three colour illuminations, or by three colour filters.
3.52.3
time sequential exposure
acquisition of a picture by combining repeated exposures to capture different spatial components
NOTE Time sequential exposure can be with a line array (line scanning) or an area array. With a line array, the picture
is acquired by optical or physical sub-scanning with an image sensor in one dimension. With an area array, repeated
exposures may integrate smaller pictures into a larger picture by means of image sensor shifting.
3.53
exposure series
series of images of the same subject taken using different exposure index values
[ISO 12232:2006, definition 3.3]
3.54
extended gamut
colour gamut extending outside that of the standard sRGB CRT display as defined by IEC 61966-2-1
[ISO 22028-1:2004, definition 3.19, ISO/TS 22028-2:2006, definition 3.13, ISO/TS 22028-3:2006, definition 3.14]
3.55
fast scan direction
scan direction corresponding to the direction of the alignment of the addressable photoelements in a linear
array image sensor
[ISO 16067-1:2003, definition 3.7, ISO 16067-2:2004, definition 3.7, ISO 21550:2004, definition 3.7]
10 © ISO 2012 – All rights reserved

3.56
file system
filing system
software structure which specifies how the data are logically organized on a given storage medium
NOTE This term is also defined in ISO 12234-1 and ISO 12234-2.
3.57
film rendering transform
mapping of image data representing measurements of a photographic negative to output-referred image data
representing the colour-space coordinates of the elements of a reproduction
[ISO 22028-1:2004, definition 3.20]
3.58
film unrendering transform
mapping of image data representing measurements of a photographic negative to scene-referred image data
representing estimates of the colour-space coordinates of the elements of the original scene
[ISO 22028-1:2004, definition 3.21]
3.59
flare
light falling on an image, in an imaging system, which does not emanate from the subject point
NOTE 1 Flare is also sometimes referred to as veiling glare.
NOTE 2 See also image flare (3.59.1), veiling flare (3.59.2), veiling glare (3.189).
3.59.1
image flare
light from a subject point that is scattered by the optical system to areas of the image plane other than the
appropriate image point
NOTE The distinction of image-flare light resulting from any subject point is specified by the image point spread
function. Point spread functions tend to fall off rapidly as the distance from the image point is increased, are variable for
different image-point locations and are typically not radially symmetric for image points some distance from the optical
systems axis.
3.59.2
veiling flare
relatively uniform but unwanted irradiation in the image plane of an optical system, caused by the scattering
and reflection of a proportion of the radiation which enters the system through its normal entrance aperture
where the radiation may be from inside or outside the field of view of the system
NOTE Light leaks in an optical system housing can cause additional unwanted irradiation of the image plane. This
irradiation can resemble veiling flare.
[ISO 3664:2009, definition 3.19]
3.60
FlashPix
image file format, defined in FlashPix Format Specification, using a structured storage file containing metadata
and a tiled, hierarchical image representation
NOTE The tiles in a FlashPix image are normally baseline JPEG images, and individual image tiles of a particular
resolution can be easily accessed for rapid display and editing.
[ISO 15740:2008, definition 3.14]
3.61
folder
optional sub-structure in a hierarchical storage area that can contain data objects
[ISO 15740:2008, definition 3.13]
3.62
gamma correction
process that alters the image data in order to modify the tone reproduction
NOTE 1 Gamma correction is performed in part to correct for the nonlinear light-output versus signal input characteristic
of the display. The relationship between the light input level and the output signal level, called the OECF, provides the
gamma correction curveshape for an image capture device.
NOTE 2 The gamma correction is usually an algorithm, lookup table, or circuit which operates separately on each
colour component of an image.
NOTE 3 This term is also defined in ISO 12233, ISO 16067-1, ISO 16067-2 and ISO 21550.
3.63
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 to compensate for differences in the source and output medium colour gamut capability
NOTE The term “gamut mapping” is somewhat more restrictive than the term “colour rendering” because gamut
mapping is performed on colorimetry that has already been adjusted to compensate for viewing condition differences
and viewer preferences, although these processing operations are frequently combined in reproduction and preferred
reproduction models.
[ISO 22028-1:2004, definition 3.22, ISO/TS 22028-2:2006, definition 3.14]
3.64
hardcopy
representation of an image on a substrate which is self-sustaining and reasonably permanent
EXAMPLE Prints, transparencies.
NOTE See also softcopy (3.166).
[ISO 3664:2009, definition 3.4, ISO 22028-1:2004, definition 3.23]
3.65
horizontal resolution
resolution value measured in the longer image dimension, corresponding to the horizontal direction for a
“landscape” image orientation, typically using a vertically oriented test-chart feature
[ISO 12233:2000, definition 3.9]
3.66
ICC profile
International Color Consortium’s file format, used to store transforms from one colour encoding to another, e.g.
from device colour coordinates to profile connection space, as part of a colour management system
[ISO 22028-1:2004, definition 3.24]
3.67
IEEE 1394
high-speed serial bus standardized by the IEEE (Institute of Electrical and Electronics Engineers) currently
having clock rates of 100, 200 and 400 Mbits/sec
NOTE IEEE 1394 is often referred to as FireWire.
[ISO 15740:2008, definition 3.17]
12 © ISO 2012 – All rights reserved

3.68
illuminance scale exposure series
series of exposures produced using a constant exposure time and a varying focal plane illuminance
NOTE See also time scale exposure series (3.181).
[ISO 14524:2009, definition 3.6]
3.69
image capture device
device for converting a scene or a fixed image such as a print, film or transparency, to digital image data
[ISO 15740:2008, definition 3.17]
3.70
image compression
process that alters the way digital image data is encoded in order to reduce the size of an image file
[ISO 12233:2000, definition 3.11]
3.71
image data format
structure and content which specify image and the organization of the image related data in a device
independent manner
NOTE This term is also defined in ISO 12234-2.
[ISO 12234-1:2007, definition 3.2]
3.72
image output device
device that can render a digital image to hardcopy or softcopy media
[ISO 15740:2008, definition 3.18]
3.73
image quality
impression of the overall merit or excellence of an image, as perceived by an observer neither associated with
the act of photography, nor closely involved with the subject matter depicted
NOTE The purpose of defining image quality in terms of third-party (uninvolved) observers is to eliminate sources of
variability that arise from more idiosyncratic aspects of image perception and pertain to attributes outside the control of
imaging system designers.
[ISO 20462-1:2005, definition 3.5, ISO 20462-3:2005, definition 3.3]
3.74
image sensor
electronic device that converts an optical image into an electronic signal; for example a charge coupled
device (CCD) array
NOTE This term is also defined in ISO 12232, ISO 15739, ISO 16067-1, ISO 16067-2 and ISO 21550.
[ISO 12233:2000, definition 3.12]
3.75
image state
attribute of a colour image encoding indicating the rendering state of the image data
NOTE The primary image states defined in this document are the scene-referred image state, the original-referred
image state and the output-referred image state.
[ISO 22028-1:2004, definition 3.25, ISO/TS 22028-2:2006, definition 3.16, ISO/TS 22028-3:2006, definition 3.15]
3.76
image storage application profile
ISAP
media profile, the filing system and the image data format
NOTE The ISAP specifies all the information necessary to completely implement the removable memory.
[ISO 12234-1:2007, definition 3.3]
3.77
in-band event
event transmitted on the same logical connection as operations and responses
NOTE Events are only asynchronous to the degree of data precision for which the transport implementation allows
event interleaving.
[ISO 15740:2008, definition 3.19]
3.78
incremental gain function
change in the output level (digital code value) divided by the change in the input level (luminance or exposure)
as a function of input level
NOTE 1 For the determination of incremental gain values, log input values are not used.
NOTE 2 If the input exposure points are very finely spaced and the output noise is small compared to the quantization
interval, the incremental gain function may have a jagged shape. Such behaviour is an artefact of the quantization process
and should be removed by using an appropriate smoothing algorithm, or by fitting a smooth curve to the data. In some
cases, it may be desirable to fit a curve to the input-output data and then determine the incremental gain function by taking
the first derivative of the function used for the curve fit.
NOTE 3 This term is also defined in ISO 15739 and ISO 21550.
[ISO 14524:2009, definition 3.7]
3.79
incremental output signal
input level (luminance or exposure, not logged) multiplied by the system incremental gain at that level
NOTE 1 See also incremental gain function (3.78).
NOTE 2 This term is also defined in ISO 21550.
[ISO 14524:2009, definition 3.8, ISO 15739:2003, definition 3.7]
3.80
incremental signal to noise ratio
ratio of the incremental output signal to the root mean square (rms) noise level, at a particular signal level
NOTE 1 The incremental signal to noise ratio is typically expressed as a graph or table showing the rms noise level
versus output signal level for the full range of output signal levels.
NOTE 2 This term is also defined in ISO 15739 and ISO 21550.
3.81
Infrared Data Association
IrDA
infrared wireless communication system that currently supports wireless communication at data rates between
9600 bps and 4 Mbps
[ISO 15740:2008, definition 3.22]
14 © ISO 2012 – All rights reserved

3.82
initiator
device that initiates a conversation by opening a session, and issues all formal operations to the responder
NOTE The initiator is analogous to the client in the client/server paradigm.
[ISO 15740:2008, definition 3.20]
3.83
instructions
set of directions given to the observer for performing the psychophysical evaluation task
[ISO 20462-1:2005, definition 3.6, ISO 20462-3:2005, definition 3.4]
3.84
International Color Consortium profile connection space (ICC PCS)
standard colour image encoding defined by the International Color Consortium providing a standard connection
point for combining ICC profiles
NOTE The ICC.1:2001 specification defines two variations of the PCS, an original-referred variation for colorimetric
intent profiles, and a standard output-referred variation for perceptual intent profiles.
[ISO 22028-1:2004, definition 3.26]
3.85
International Imaging Industry Association
I3A
organization that serves to represent the common interests among manufacturers of imaging technology products
NOTE See http://www.i3a.org.
[ISO 15740:2008, definition 3.21]
3.86
ISO DSC dynamic range
ratio of the maximum luminance level that appears unclipped to the minimum luminance level that can be
reproduced with an incremental signal-to-temporal-noise ratio of at least 1, as determined according to ISO 15739
[ISO 15739:2003, definition 3.9]
3.87
ISO scanner dynamic range
difference of the maximum density where the incremental gain is higher than 0,5, as determined according to
ISO 21550, and the minimum density that appears unclipped
[ISO 21550:2004, definition 3.13]
3.88
ISO speed
numerical value calculated from the exposure provided at the focal plane of a DSC to produce specified
camera output signal characteristics using the methods described in ISO 12232
NOTE 1 The ISO speed is usually the highest exposure index value that still provides peak image quality for normal
scenes. However, a DSC does not necessarily use the ISO speed value as the exposure index value when capturing images.
NOTE 2 This term is also defined in ISO 12232.
3.89
ISO speed latitude
set of two numerical values calculated from the exposure provided at the focal plane of an electronic camera to
produce specified camera output signal characteristics using the methods described in ISO 12232
NOTE 1 The ISO speed latitude is expected to correlate with the range of exposure index values that provide acceptable
image quality for normal scenes.
NOTE 2 This term is also defined in ISO 12232.
3.90
Joint Photographic Experts Group
JPEG
specific image compression method defined in ISO/IEC 10918-1
[ISO 15740:2008, definition 3.23]
3.91
just noticeable difference
JND
stimulus difference that leads to a 75:25 proportion of responses in a paired comparison task
NOTE 1 See also attribute JND (3.15) and quality JND (3.143).
NOTE 2 This term is also defined in ISO 20462-3.
[ISO 20462-1:2005, definition 3.7]
3.92
limiting resolution
value of that portion of a specified resolution test pattern, measured in line widths per picture height, which
corresponds to an average modulation value equal to some specified percentage of the modulation value at a
specified reference frequency
EXAMPLE The limiting resolution could be the test pattern value, in line widths per picture height (LW/PH), corresponding
to a camera output modulation level of 5 % of the camera output modulation level at a reference frequency of 10 LW/PH.
NOTE This term is also defined in ISO 12233.
3.93
line pairs per millimetre
lp/mm
metric for specifying resolution in terms of the number of equal width black and white line pairs per millimetre
that can be resolved according to some criterion, such as visual resolution or limiting resolution
NOTE 1 Distance units other than millimetres can also be used.
NOTE 2 This term is also defined in ISO 12233.
3.94
line spread function
LSF
normalized spatial signal distribution in the linearized output of an imaging system resulting from imaging a
theoretical infinitely thin line
NOTE If the imaging system is operating in an isoplanatic region and in its linear range, the LSF is equal to the first
derivative of the ESF.
[ISO 12233:2000, definition 3.16]
16 © ISO 2012 – All rights reserved

3.95
LogicalStorageID
least significant sixteen bits of a Storage ID
NOTE This value uniquely identifies one logical storage area within the physical store indicated in the PhysicalStorageID.
[ISO 15740:2008, definition 3.24]
3.96
line widths per picture height
LW/PH
metric for specifying the width of a feature on a test chart, relative to the height of the active area of the chart,
which is equal to the height of the active area of the test chart divided by the width of a black line, that is equal to
the total number of lines of the same width which can be placed edge to edge within the height of a test target,
or within the vertical field of view of a camera
NOTE If the height of the active area of the chart equals 20 cm, a black line of 1 000 LW/PH has a width equal to 20/1 000 cm.
[ISO 12233:2000, definition 3.17]
3.97
linearized
digital signal conversion performed to invert the camera opto-electronic conversion function (OECF) so that
the resulting signal is approximately linearly proportional to the scene luminance
[ISO 12233:2000, definition 3.18]
3.98
lines per millimetre
lines/mm
m
...