The performance of object detection, to a great extent, depends on the availability of large annotated datasets. To alleviate the annotation cost, the research community has explored a number of ways to exploit unlabeled or weakly labeled data. However, such efforts have met with limited success so far. In this work, we revisit the problem with a pragmatic standpoint, trying to explore a new balance between detection performance and annotation cost by jointly exploiting fully and weakly annotated data. Specifically, we propose a weakly- and semi-supervised object detection framework (WSSOD), which involves a two-stage learning procedure. An agent detector is first trained on a joint dataset and then used to predict pseudo bounding boxes on weakly-annotated images. The underlying assumptions in the current as well as common semi-supervised pipelines are also carefully examined under a unified EM formulation. On top of this framework, weakly-supervised loss (WSL), label attention and random pseudo-label sampling (RPS) strategies are introduced to relax these assumptions, bringing additional improvement on the efficacy of the detection pipeline. The proposed framework demonstrates remarkable performance on PASCAL-VOC and MSCOCO benchmark, achieving a high performance comparable to those obtained in fully-supervised settings, with only one third of the annotations.

本文提出了一种弱/半监督目标检测框架(WSSOD)，通过在联合数据集上训练代理检测器，进而在弱标注图像上预测伪包围框，提出了弱监督损失(WSL)、标签注意力和随机伪标签采样策略来放宽当前半监督流程的假设，并为检测管道的有效性带来额外的改进。这个框架在PASCAL-VOC和MSCOCO基准测试中展示了显著的性能，只有三分之一的注释数据就能达到与完全监督相同的高性能。

WSSOD: 弱监督和半监督目标检测的新流水线