Hi Curious Thinker,
I understand that you want to extract independent subspace components (ISA) from independent component analysis (ICA) components of an image and then perform an inverse operation to reconstruct the image.
I assume you have already computed the ICA components.
In order to find the independent subspace components and perform the inverse operation, you can follow the below steps:
Compute ICA Components:
First, ensure you have the ICA components of your image. You can use the “fastica” function to achieve this.
[icaComponents, ~, ~] = fastica(imageData);
Group ICA Components:
Group the ICA components into subspaces. This can be done by clustering or manually defining groups based on your understanding of the data.
% Example: Group first two components together
subspace1 = icaComponents(1:2, :);
Compute ISA Components:
For each subspace, compute the ISA components by projecting the ICA components onto the subspace.
isaComponents = subspace1 * subspace1';
Inverse ISA Transformation:
To reconstruct the image, perform an inverse transformation using the ISA components and the mixing matrix.
reconstructedImage = isaComponents * mixingMatrix';
Example Reconstruction:
Display the reconstructed image to verify the inverse transformation.
imshow(uint8(reconstructedImage));
Refer to the documentation of “fastica” function to know more about its usage:
Hope this helps!
