Should unique vectors (SIFT descriptors) be used in K-Means Clustering? I'm doing image classification by extracting SIFT features, clustering them and then finding BOVW histogram and classifying.

I have around 180 training images from which I'm extracting SIFT descriptors. I need to cluster these features using k-Means clustering. Now, among the SIFT descriptors, some are duplicate. Before applying K-Means, should I remove these duplicate vectors or should I not? Or does it not make any difference?

Thanks!
It does make a difference.

If you have many duplicates, you can merge them into weighted vectors. It's straightforward to add to existing code.