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Image interpolation online

Hello,

URL of experiment: https://run.pavlovia.org/atomsrivet/test_image_interpolation/html/

Description of the problem:
My online experiment appears to always use linear interpolation even when I set interpolation to nearest/False. I would appreciate any help/tips on how to solve this. I’ve attached screenshots from the experiment (attached url) when I run it in the builder vs when I run it online.

The screenshot consists of the same image displayed twice side by side. On the left, I’ve specified interpolation as nearest neighbor, on the right - i’ve specified it as linear. While in the builder, the image appears appreciably different between the two settings, in the browser, the image appears the same - and as linear interpolation rather than nearest neighbor.

here is a screenshot as the images appear in the builder:

here is a screenshot as the images appear in the browser:

Thank you in advance for the assistance!

Issue solved! Unfortunately, it appears that options.interpolate in PsychoJS ImageStim doesn’t function as expected (images are always interpolates linearly, regardless of setting options.interpolate to true or false). However, I found a workaround which serves my purposes - since the rendering of ImageStim is based on PixiJs, I directly edited the PixiJs interpolation setting by inserting

PIXI.settings.SCALE_MODE = PIXI.SCALE_MODES.NEAREST;

via the code component.

Note that this workaround works great for me since I want all my stimuli to not be linearly interpolated. It wouldn’t work if you wanted to simultaneously present one image with applied linear interpolation, the other without. To go back to linear interpolation, inserting

PIXI.settings.SCALE_MODE = PIXI.SCALE_MODES.LINEAR;

in the code component does the trick!