How to classify using PCA ("pcares" function)

Hello.

I want to do a video classification.

I found some function about PCA.

https://www.mathworks.com/help/stats/pcares.html

[residuals,reconstructed] = pcares(X,5)

After using pcares(X,5), Can I classify data using "reconstructed"?

I mean, "reconstructed" is 3600 x 25.

1. After flattening each data, I got 90000 X 1.

2. I have 90 data, so I got 90 X 90001 (the last column is class).

3. Using classification methods like SVM, KNN, etc.

4. calculate the accuracy of the classification.

Is it a reasonable approach? or do I need to use other methods as PCA not "pcares".

When I use "reconstructed" data after "pcares", the accuracy of classification is so low.

Please let me know how to deal with this issue.