The development of the OCTA toolbox:
An accessible, open-source tool to create
flexible and reproducible visual displays
Eline Van Geert, Christophe Bossens, & Johan WagemansLaboratory of Experimental Psychology, KU Leuven, Belgium
Aim of OCTA
Create reproducible and flexible multi-element displays varying qualitatively and quantitatively in:
ORDER 
structure and organization
structure and organization
COMPLEXITY 
quantity and variety
quantity and variety
available as a free tool for programmers (as a Python library) and non-programmers (as an online Shiny app)
1 Create stimulus & 2 Add positions
Specify stimulus type (Grid, Outline, Concentric) and stimulus features (e.g., orientation, background color)
Specify position pattern for elements
Create2DGrid
CreateSineGrid
CreateRandomPositions
CreateCircle
CreateShape
CreateCustomPositions
Test OCTA
but can also be used by broader public
to easily create interesting visual displays
3 Add feature patterns and pattern values & 4 Add deviations & 5 Save and recreate the stimulus
Features (including dynamic feature options!)
shapes
fillcolors
boundingboxes
orientations
borderwidths
bordercolors
opacities
mirrorvalues
shapes
fillcolors
boundingboxes
orientations
borderwidths
bordercolors
opacities
mirrorvalues
additional non-visual features: links, classlabels, idlabels
Pattern types
Repeat
ElementRepeat
Mirror
Gradient
Random
TiledGrid
TiledElementGrid
Repeat
ElementRepeat
Mirror
Gradient
Random
TiledGrid
TiledElementGrid
Pattern directions
AcrossElements
AcrossRows
AcrossColumns
AcrossLeftDiagonal
AcrossRightDiagonal
AcrossLayers
AcrossElements
AcrossRows
AcrossColumns
AcrossLeftDiagonal
AcrossRightDiagonal
AcrossLayers
Position and element deviations
position jitter
position deviations
swap elements
randomize elements
remove elements
Feature deviations
swap features
change features
randomize features
jitter features
position jitter
position deviations
swap elements
randomize elements
remove elements
swap features
change features
randomize features
jitter features
Output options
- stimulus as vector or raster image
- computer-readable output to recreate the stimulus in Python with the LoadFromJSON function
- in the online app: download or view the Python code
Interactive online applications
Make research data available for exploration by a broader audience in an easy and interactive way: OCTA ratings app
Why use OCTA?
- varying qualitatively or quantitatively in order and/or complexity
- reproducible, adjustable, and open source
- easy to create
- tailored for online use
- static or dynamic
- multimodal (adding sound is possible using Javascript)
- …
Contact
Eline Van Geert - eline.vangeert@kuleuven.be
supported by a Ph.D. fellowship of the Research Foundation - Flanders (FWO)
supported by a Ph.D. fellowship of the Research Foundation - Flanders (FWO)
DigiSoc Launch Event 2021 - October 26th - Leuven