Principal Component Analysis for feature extraction

Hi. I'm learning about PCA and wanted to learn how it can be used for feature extraction and if it is feasible to extract features using PCA? Also I don't understand when exactly is PCA used in image processing. From what I understand it is used to reduce the size of a dataset and then features are extracted from that dataset using some other methods such as GLCM. Am I correct?

[Aya Ahmed]

Have you reached a solution?

Answer 1

[deepak panday]

[coff,score]=pca(data) newData = data*coff(:,1:n)

where n is number of feature to selected.

[Aya Ahmed]

deepak panday

this line code only for PCA feature extraction?

[Aya Ahmed]

how can i apply this code on real images??