CIE Primary System

Hello,

we would like to transform colormeasurementpictures, where the chromaticity coordinates are in the CIE-RGB primary system, into a format, that can be used in the radiance program. Unfortunately the used colorspace of the radiance program is not the CIE-RGB-system. So the displayed luminance values are not correct. We have tryed to change the primary values in the header of the convertet .pic file, but the result of the shown picture and the shown luminance value is not correct. In the below-mentioned diagram i've shown you both used RGB-primary-systems. In the diagram the orange triangle is the CIE-RGB-System and the blue one the radianceused system. As you can see they do not fit very well.
Could you please tell me, which primarysystem is used for radiance? Do you have an idea how we can make our measurementfile with the radiance program compartible?

sincerely<http://dict.leo.org/ende/index_de.html#/search=sincerely&searchLoc=0&resultOrder=basic&multiwordShowSingle=on&pos=0> yours<http://dict.leo.org/ende/index_de.html#/search=yours&searchLoc=0&resultOrder=basic&multiwordShowSingle=on&pos=0>
Dipl. -Ing. Katharina Jungnitsch

[cid:[email protected]]

TechnoTeam Bildverarbeitung GmbH
Werner - von - Siemens - Strasse 5
98693 Ilmenau

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Email: [email protected]<mailto:[email protected]>
Phone: +49 3677 4624 0

Hi Katharina,

maybe this little-known converter may already do the job:

http://radsite.lbl.gov/radiance/man_html/ra_xyze.1.html

The header of a compressed Radiance hdr-image with pixel values in XYZ (2 deg. observer) looks like:

FORMAT=32-bit_rle_xyze

While the RGB counterpart would be lack this format-line.

Paul Bourke wrote a nice overview on the format: http://paulbourke.net/dataformats/pic/

For some further reading, discussions on color in Radiance show up from time to time on the list, e.g.:

http://www.radiance-online.org:82/pipermail/radiance-general/2015-June/010999.html

The standard primaries are in src/common/color.h and set to

R: 0.640 0.330
G: 0.290 0.600
B: 0.150 0.060
W: 0.333 0.333

Cheers,
Lars.

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Am 11.10.16 um 14:52 schrieb Katharina Jungnitsch:

Hello,

we would like to transform colormeasurementpictures, where the chromaticity coordinates are in the CIE-RGB primary system, into a format, that can be used in the /radiance/ program. Unfortunately the used colorspace of the /radiance/ program is not the CIE-RGB-system. So the displayed luminance values are not correct. We have tryed to change the primary values in the header of the convertet .pic file, but the result of the shown picture and the shown luminance value is not correct. In the below-mentioned diagram i�ve shown you both used RGB-primary-systems. In the diagram the orange triangle is the CIE-RGB-System and the blue one the /radiance/used system. As you can see they do not fit very well.

Could you please tell me, which primarysystem is used for /radiance/? Do you have an idea how we can make our measurementfile with the /radiance /program compartible?

sincerely <http://dict.leo.org/ende/index_de.html#/search=sincerely&searchLoc=0&resultOrder=basic&multiwordShowSingle=on&pos=0> yours <http://dict.leo.org/ende/index_de.html#/search=yours&searchLoc=0&resultOrder=basic&multiwordShowSingle=on&pos=0>

Dipl. �Ing. Katharina Jungnitsch

TechnoTeam Bildverarbeitung GmbH
Werner - von - Siemens - Strasse 5
98693 Ilmenau
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Email: [email protected] <mailto:[email protected]>

Phone: +49 3677 4624 0

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