240605 (hand) 1L2L0X0E_(I), http://farbe.li.tu-berlin.de/AEAI.HTM or http://color.li.tu-berlin.de/AEAI.HTM
For this main page with general information and special images, see
AEAI in English,
AGAI in German.
For this main page with general information and special images
Chapter A: Colour Image Technology and Colour Management (2019),
Main part AEAI
Remark: Until today there is no specific text on the following pages:
AEII, AEJI, up to AEVI.
Specific text is on the pages:
AEBI bis AEHI und
AEWI bis AEZI.
For links to the next chapter B, see
BEAI in English,
BGAI in German.
of the corresponding image page with 10 colour series, see
AEAI in English,
AGAI in German.
For links to this chapter A
Colour Image Technology and Colour Management (2019),,
see
Content list of chapter A:
AEA_I in English or
AGA_I in German.
Example image part of 26 parts AEAS to AEZS:
AEAS in English or
AGAS in German.
For links to the next chapter B
Colour Vision and Colorimetry (2020),,
see
Content list of chapter B:
BEA_I in English or
BGA_I in German.
Example image part of 26 parts feas to fezs:
BEAS in English or
BGAS in German.
Since about 2000 the colour-information technology has developed
in different directions.
The ISO Committees TC 42 (Photography), TC 130 (Professional print),
TC 159 (Ergonomics - Display requirement), TC 171 (Document management),
and ISO/IEC SC28 (Office system) have developed many specific
isolated colour standards for their devices.
In 2017, and after about 15 years the ISO Committee ISO-SCIT
(Steering Committee for Image Technology)
was closed. The members could not reach the goal for more common
instead of isolated standards.
For example the interests of industrial members are too different.
Since 2019 a new ISO guide for ISO standardization requires a balance
of the net benefit of users and of industrial interests.
For example ergonomic requirements are described in rules
for display-work places, see
ISO 9241-306. Applications of ergonomic rules for colour printers,
professional print, colour cameras,
and scanners can improve the net benefit and the health of all users.
This is also true for the home office with display workplaces.
Often a fast fatigue of users
can be avoided by an ergonomic design.
2. Colour reproduction loop
The reproduction of the colour data rgb* and cmyk*
of 1080 colours
in the ISO file AG49 is possible after print and scan with a high precision.
Figure 1 shows the reproduction loop for this general goal.
For the download of Figure 1 in the VG-PDF format, see
AEA21-4N.PDF.
In Figure 1 the abbreviation 100% Under Colour Removal (UCR) means, that all grey colours are only printed with the colorant black N, and not with three chromatic colorants C, M, and Y. If the three chromatic colorants C, M, and Y are twice as expensive as black N, then the print costs reduce with 100% UCR by up to a factor 6. In addition the important achromatic stability of the print is increased. In the case of an illuminant change a chromatic tint of the image is usually avoided.
3. ISO file AG49 according to ISO 9241-306:2018
The realisation of the colour-reproduction loop is managed
with the ISO rgb*-colour file.
This file is reproduced on the display and in the print by colorimetric
and at the same time
ergonomic criteria. A colorimetric scanner produces approximately
the rgb*-colour data
of the ISO-start file.
Figure 2 shows a 1MR-modification of the ISO file which is referred
in Figure 1.
For the download of Figure 2 in the VG-PDF format, see
AEA21-3N.PDF.
For the download of the ISO file in the VG-PDF format, see
http://standards.iso.org/iso/9241/306/ed-2/AE49/AE490-7N.PDF
.
4. 1-Minus-Relation (1MR) for rgb and cmyk
colour data
In Figure 2 all cmyk-colour data in this ISO file are changed
by the 1-Minus-Relation (1MR)
into rgb-colour data. For example it is valid:
r = 1 - c, g = 1 - m, b = 1 - y.
[1]
There is software, for example Win Adobe FrameMaker V8,
which does the changes according to 1MR automatically.
Then the output file includes only rgb data similar as in Figure 2.
The necessary second change of rgb- into cmyk-colour data
is done internally
by the printer manufacturers within the so called RGB printers.
The intended output steering with 100% UCR is possible for proof printers
in the graphical area,
and with all PostScript printers
A output steering by users is therefore not possible with the RGB
printers in the consumer area.
However, consumers request ergonomic printers with colorimetric possibilities
for output steering.
Methods are known and can not be applied for RGB printers.
5. Standardisation in colour-information technology:
Devices and colorimetric ergonomy
Many properties of printers and displays can be tested
with the standard series DIN 33872-1 to 6:2010, see
http://farbe.li.tu-berlin.de/A/33872E.html.
For additional ISO-test charts according to ISO/IEC 15775:1999,
and ISO/IEC TR 24705:2005 see
http://farbe.li.tu-berlin.de/A/24705TE.html.
For the ergonomic output on displays the same test charts are described
according to
ISO 9241-306:2018 in english, french and german with many output questions,
see
http://standards.iso.org/iso/9241/306/ed-2/index.html.
Figure 3 shows the relations of many standard documents.
For the download of Figure 3 in the VG-PDF format, see
EE680-3N.PDF.
Figure 4 shows the relations of many standard documents with links.
For the download of Figure 4 in the VG-PDF format, see
EE681-3N.PDF.
There is free download of many of these standard documents and test charts.
For a part of the German standards international standards
(for example ISO/IEC DIS 19839-1 to -4)
were not possible. The corresponding ISO/IEC TR 24705 was deleted in 2019.
The interests of the industry and of users are opposite,
for example the industry tries to
sell much colour materials. For the ergonomic output
the users need usually much less
colour material. A balance and steering according to the
ISO net-benefit criteria seems not possible up to now.
Additional remarks and papers
Information about test charts of ISO, IEC, CEN, and DIN
according to ISO CEN 9241-306:2018 for the test of display output,
and for eight contrast steps in english (E), german (G), and french (F).
The test charts are on the ISO Standards Maintenance Portal
in the file formats PDF, and PostScript (PS, TXT), see
http://standards.iso.org/iso/9241/306/ed-2/index.html
Richter, Klaus (2019), Colour Topics in the CIE and Applications,
Annual conference of the German Society for Color Science (DfwG),
Leipzig, October 2019, 21 slides, 900 KB, see
_DfwGE_19.PDF
Richter, Klaus (2019), Colorimetric scan, display, and print for
archiving based on
the ergonomic International Standard ISO 9241-306:2018 at work places,
paper ARCH2019_Richter_PG_111.pdf within the book Archiving2019, Lisbon,
Portugal, Society for Imaging Science and Technology.
For the application of the "anti chromatic
Ostwald-Optimal colours"
see the following two reports for free download. If the first link
in the standard-MLA format
from the CIE web site does not work, then the second link produces
the download from the WBM-archive server.
Thorstein Seim (2009), Reportership Report CIE R1-47, Hue angles
of elementary colours,
see (35 pages),
[
http://files.cie.co.at/526.pdf]._Internet Archive_.[
http://web.archive.org/web/20160304130704/http://files.cie.co.at/526.pdf].
Thorstein Seim (2013), Reportership Report CIE R1-57, Border between Blackish
and Luminous Colours,
see (23 pages),
[
http://files.cie.co.at/716_CIE%20R1-57%20Report%20Jul-13%20v.2.pdf]
._Internet Archive_.[
http://web.archive.org/web/20150413002133/http://files.cie.co.at
/716_CIE%20R1-57%20Report%20Jul-13%20v.2.pdf].
Richter, Klaus (2016), Output linearization method OLM16
for displays, printers, and offset print
(61 pages, 1,3 MB, Format A4) with updated links in 2019, see
OUTLIN16_01.PDF
The technical content of this paper is approximately equal to the
Reportership Report CIE R8-09:2015.
This report is freely available only for members of CIE Division 8
"Image Technology".
CIE 230:2019, Validity of formulae for prediction small colour differences,
developed by CIE TC1-81 with the chairman: Richter, Klaus,
see for a summary at
http://www.cie.co.at/publications
/validity-formulae-predicting-small-colour-differences.
The last four papers include device independent rgb*-, cmyk*-,
and Lab*-colour data for the definition of standard metadata.
Standard metadata are necessary for the 1080 colours
of the ISO-test chart AE49.
Standard metadata are used for input linearization of scanners and cameras
and the output linearization of printers and displays.
For output and input linearization in a general case 16,7 million
(=256 x 256 x 256) colour data
shall be changed to 16,7 million other data. With a laptop computer
this is possible within less than a second.
The transformation table (Look_up_table) is calculated
from the Lab*-measurement data of
729 (=9 x 9 x 9) colours in the rows 1 to 27 and the columns A to X
of the test chart AE49, see K. Richter (2016).
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For the archive information (2000-2009) of the BAM server "www.ps.bam.de"
(2000-2018)
about colour test charts, colorimetric calculations,
standards, and publications, see
indexAE.html in English,
indexAG.html in German.
Back to the main page of this TUB web site (NOT archive), see
index.html in English,
indexDE.html in German.