How can i convert some of images Matrices to be square symmetric Matrices?

Plz help ..How can i convert some of images Matrices to be square symmetric Matrices To apply PCA on them ,, because principal component analysis is performed on a square symmetric matrix.

Answer 1

[Image Analyst]

Matrices do not need to be square to do PCA on them. Attached is an example where I do PCA on the 3-D color gamut of an RGB image. Plus another example on a point cloud.

[Aya Ahmed]

Image Analyst..i want to make feature extraction using PCA on some images , and this images with different dimentions , and i want to make them standard dimentions ,, what can i do that ?

when i read about PCA for feature extraction i found that the PCA deal with square symmetric matrix

can i apply PCA on different dimentions images?

[Image Analyst]

PCA doesn't depend on the image dimensions. Do you mean that you have some features that don't have the same number of observations as in other images? What are your features?

[Aya Ahmed]

I want to make feature extraction on some images using Fusion between Morphological features(iam macking that using matalb code and get result)+ PCA features (i cant do that any more )

I want io make:

Morphological features with 4pc containing 70 % of original image ,

Morphological features with 8pc containing 75 % of original image,

Morphological features with 16pc containing 80 % of original image,

Morphological features with 24pc containing 85 % of original image) ,

and those images were with standard dimentions 255*255 before macking to them rotated cropped. after making rotate and crop, they become like this image with different dimentions in wide and high.

how can i make pca matlab code to do that please ??

i resarched about pca alot to make that , but i cant reach to any result , I kept looking for two months in this point

[Aya Ahmed]

Do you anow any another efficient method to make feature extraction ?