@greeness answer の助けを借りて、サブクラスを作成しましたCvBoost
std::vector<int> RSCvBoost::getFeatureIndexes() {
CvSeqReader reader;
cvStartReadSeq( weak, &reader );
cvSetSeqReaderPos( &reader, 0 );
std::vector<int> featureIndexes;
int weak_count = weak->total;
for( int i = 0; i < weak_count; i++ ) {
CvBoostTree* wtree;
CV_READ_SEQ_ELEM( wtree, reader );
const CvDTreeNode* node = wtree->get_root();
CvDTreeSplit* split = node->split;
const int index = split->condensed_idx;
// Only add features that are not already added
if (std::find(featureIndexes.begin(),
featureIndexes.end(),
index) == featureIndexes.end()) {
featureIndexes.push_back(index);
}
}
return featureIndexes;
}