FasterRCnn use DetectionOutput as inference results. In source code it is written

// num() and channels() are 1.
// Since the number of bboxes to be kept is unknown before nms, we manually
// set it to maximal number of detections, [keep_top_k] parameter multiplied by batch size.
// Each row is a 7 dimension std::vector, which stores
// [image_id, label, confidence, xmin, ymin, xmax, ymax]

Can we add this comment in detectionOutput layer doc?