{'loss_classifier': tensor(0.2094, grad_fn=<NllLossBackward0>), 'loss_box_reg': tensor(0.0927, grad_fn=<DivBackward0>), 'loss_objectness': tensor(0.0407, grad_fn=<BinaryCrossEntropyWithLogitsBackward0>), 'loss_rpn_box_reg': tensor(0.0073, grad_fn=<DivBackward0>)}
{'boxes': tensor([], size=(0, 4), grad_fn=<StackBackward0>), 'labels': tensor([], dtype=torch.int64), 'scores': tensor([], grad_fn=<IndexBackward0>)}