psychopy.org | Reference | Downloads | Github

Is it possible to make Vanishing optotype (similar to as attached below) using PsychoPy?


#1

Hi All, I would like to make some vanishing optotypes for my experiment and was wondering if I can make them via PsychoPy.

vanishingoptotype-146826C30452425D8A9-thumb400

Thank you so much for your help in advance.

Best Wishes,

Nabin


#2

Can you provide more details?


#3

Basically, I would like to make various optotypes on a grey background with borders consisting of black and white stripes wherein the combined luminance of the border must be similar to the background at a particular distance. (please see picture below) Also I would like the black and white stripe to become narrower and narrower with different difficulty level. vanishingoptotype-146826C30452425D8A9-thumb400


#4

That’s an interesting one. It’s not so much of a PsychoPy-specific question as a Python programming one, though. If each line in your figure can be defined as a mathematical function, then yes, I guess you could in a relatively straightforward way.

If you want to take a pre-existing piece of line art and generate a figure from it, that would require some fancy image processing algorithm I guess. How do others do it? (i.e. are there useful details given in methods sections of relevant papers that could be used a s a guide).


#5

I don’t have it available here, but I have a program where I make a polygon blink by changing the opacity based on time. I set a variable in a code object for the opacity and set it with something like

opacity = 0.5*cos(2*pi*t)+0.5

I suppose you could do something similar to make your optotype vanish.