rhodricusack / diffeomorph Goto Github PK

Hi,

I am a undergraduate student at Western Sydney University wanting to create controlled scrambled stimulus images for a python coded psychology experiment using your code to create diffeomorphic transformations in MatLabs. My stimulus images are Mooney faces that I have created using a parametric machine model algorithm with JavaScript in VCS from another author. The problem however is that i am very inexperienced at using MatLabs and cannot figure out how to use your code. I have read the associated paper you provided in the GitHub description to try better understanding how the code works however that did not translate into anything helpful when it came down to me actually trying to run the code. Do you have any detailed instructions or tips that could help me use your code?

Kind regards,
Kiran.

Hi! I've been looking at your Time to wave good-bye to phase scrambling paper and I've noticed a couple potential issues with your calculation of the diffeomorphed coordinates on lines 141 and 142 but wanted to check my understanding before submitting a pull request.

First, according to formula (2) in your paper (which is missing a cosine maybe?) it seems that there are different random amplitude scalings (a_i) chosen for each flow field calculation ( f_i ). The value for a_i used in both lines 141 and 142 are the same, should a also have a page subscript in the same way that your p_i values do?

Second, you seem to be doing matrix multiplication on the matrices, but from my reading of the logic, is it perhaps an elementwise multiplication that's needed?

Thanks for any clarifications on this!

Hi,

I am trying to run your code on Matlab to diffeomorph some .jpg files for an fMRI task. However, I get this error

**Index in position 1 is invalid. Array indices must be positive integers or logical
values.

Error in diffeomorphic (line 63)
Im((x1+1):(x1+Psz(1)),(y1+1):(y1+Psz(2)),:)=P;**

Since I am new to Matlab, can you give me a hint on how to make it work?
Thank you so much :)

Hi there,

I am attempting to use your code to create diffeomorphed versions of 92 images.
I have attempted changing my root folders where the images are stored, but when I run the code, Figure 10 is blank and no images are passed to the output directory.

Is there anything obvious I am doing wrong? Would really appreciate your input!

Many thanks

Hello,

I am trying to scramble some images using your code. I am setting a picpath and outpicpath

picpath='Z:\15\A_44_RL\Projekt 2 fNIRS\Bilder'
outpicpath='Z:\15\A_44_RL\Projekt 2 fNIRS\Bilder\scrambled'

The outpicpath gets created correctly, and then a figure window opens named "figure 10" which I suppose, corresponds to this line of code

figure(10);

However, no scrambled image is being created in my outpicpath.

How exactly is this code supposed to be run?

Happy if you find time for assistance.

Best,

Raphael Lorenz-de Laigue