Lightness perception in
high-dynamic range images: local and remote effects
Supplemental Material
Sarah R. Allred, Ana Radonjic, Alan Gilchrist &
David H. Brainard
This page contains links
to the supplementary material associated with the manuscript "Lightness
perception in high-dynamic range images:local and remote effects"
Stimulus
characterization
- Checkerboard
Luminance: Each column contains luminance values for the checks in
the labeled context. Each row contains the luminance values for a
different location in the 5 by 5 checkerboard. Locations
are ordered from top left (1) to bottom right 25) in columns, so the
the first row corresponds to location (1,1), second row to location
(2,1), sixth row to location (1,2) etc. Location 13 (center of the
checkerboard) is the target patch location, labeled here as NaN.
- Inner Ring Checkerboard
Luminance: As above, each column contains luminance values for the
checks in the labeled context. Each row contains values for a different
checkerboard location. Here locations are those immediately surrounding
the center target patch. Referenced to the full checkerboard, this file
contains ordered values (7, 8, 9,12, 14, 17, 18, 19);
- Outer Ring Checkerboard
Luminance: As
above, each column contains luminance values for the checks in the
labeled context. Each row contains values for a different checkerboard
location. Here locations are those in the outer ring of the
checkerboard, remote from the center patch. Referenced to the
full checkerboard, this file contains
ordered values (1, 2, 3, 4, 5, 6, 10, 11, 15, 16, 20, 21, 22, 23, 24);
- Palette
Measurements: Each row contains data for one of the 16 Munsell
papers. The first column is the Munsell value for that paper (2.0 -
9.5). The second column is the nominal reflectance of the paper. The
third column is the measured reflectance of the paper, and the fourth
column is the measured luminance of the paper under fluorescent
illumination. Note that this is not the same illumination as that under
which the experimental data were collected.
- Target
patch characterization:
In addition to the regular lab calibration routines, we made 97
luminance and chromaticity measurements (using PR-650) of different
target patches. Each row contains data for a different
measurement: the first column is the requested intensity [between 0 and
1], the second column is the luminance of the displayed value, and the
third and fourth columns represent x and y chromaticity values,
respectively.
Data
The following files contain average luminance
of target patches matched to different Munsell papers. Each row
represents data matched to a different Munsell paper, sorted in
ascending order (first row is Munsell 2.0, second row is Munsell 2.5
... last row is Munsel 9.5). Each column contains data for the
labeled checkerboard context. Data were recorded as log10 luminance.
Each checkerboard
file below contains the matches for each observer. The first word
indicates the luminance profile of the inner ring, and the second word
indicates luminance profile of the outer ring. Each row contains
data for a different Munsell paper (as above), and each value
represents the average of all target patches matched to a Munsell paper
for the labeled observer.
The following files contain the out of range
judgments (darker than 2.0, lighter than 9.5). Each row represents a
different target patch, sorted in ascending order from lowest to
highest. Each column represents the labeled checkerboard context, and
the integer indicates the total number of trials on which that target
patch was judged as out of range. There are 21 judgments for each
stimulus (3 trials x 7 observers).