Hello, I am trying to use SVM for face recognition. Since SVM is highly dependent to the parameters, accurate parameter estimation is crucial. I tried to use train_auto with a pre 3.0 version, but I got error "Bad argument (While cross-validation one or more of the classes have been fell out of the sample. Try to enlarge <cvsvmparams::k_fold>) in CvSVM::do_train". I have 200 subjects of 2 samples for each class (ba, bj subset of FERET database). What could be done to overcome this error? I tried different k 's for cross validation but did not work.