Making a graph with images

Hello!

I have a set of 5 images, all different degrees of a scrambled image named scrambled_10.png [...] scrambled_50.png. I have it set so that people have to respond 1 for 'no image' and 2 for 'image present'. I want to create a graph with the degree of scrambled image on the X axis going from 10-50 and the Y axis to be the proportion of times the person responds 2. The issue is I do not know how to create the X axis as my values are associated to images. Is there a way to have MatLab create an associated numerical value to each image?

I also want to find the absolute threshiold at which the person said '2' 50 of the time, and the X axis value can be a number between 2 images, so say I only have images for 30% and 40%, the absolute threshold could equal a value of 35% if that makes sense?

Please send me any links that might help me with this problem! Thank you!

Answer 1

[Walter Roberson]

The following shows how to convert everything from after the first _ to the extension as a number. The degree can include fractions. (If you do not need fractions then the code can be simplified.)

Note: this particular implementation will fail if you have additional underscore in the basic file name.

ImageName = 'scrambled_47.2.png';

[~, basename] = fileparts(ImageName);
ScrambleDegree = str2double(regexp(basename, '(?<=_).*$', 'match'))

ScrambleDegree = 47.2000