@param class_ids a set of corresponding class ids. Ids are integer and usually start from 0.
.        * @param score_threshold a threshold used to filter boxes by score.
.        * @param nms_threshold a threshold used in non maximum suppression.
.        * @param indices the kept indices of bboxes after NMS.
.        * @param eta a coefficient in adaptive threshold formula: \f$nms\_threshold_{i+1}=eta\cdot nms\_threshold_i\f$.
.        * @param top_k if `>0`, keep at most @p top_k picked indices.