Reconstructs vectors from their PC projections

X = pca.backProject(Y)

Input

• Y coordinates of the vectors in the principal component subspace, the layout and size are the same as of cv.PCA.project output vectors.

Output

• X reconstructed vectors; the layout and size are the same as of cv.PCA.project input vectors.

The method is the inverse operation to cv.PCA.project. It takes PC coordinates of projected vectors and reconstruct the original vectors. Unless all the principal components have been retained, the reconstructed vectors are different from the originals. But typically, the difference is small if the number of components is large enough (but still much smaller than the original vector dimensionality). As a result, PCA is used.