We present region-based, fully convolutional networks for accurate and efficient object detection. In contrast to previous region-based detectors such as Fast/Faster R-CNN that apply a costly per-region subnetwork hundreds of times, our region-based detector is fully convolutional with almost all computation shared on the entire image. To achieve this goal, we propose position-sensitive score maps to address a dilemma between translation-invariance in image classification and translation-variance in object detection. Our method can thus naturally adopt fully convolutional image classifier backbones, such as the latest Residual Networks (ResNets), for object detection. We show competitive results on the PASCAL VOC datasets (e.g., 83.6% mAP on the 2007 set) with the 101-layer ResNet. Meanwhile, our result is achieved at a test-time speed of 170ms per image, 2.5-20x faster than the Faster R-CNN counterpart. Code will be made publicly available.

本论文涉及基于区域的检测器，使用卷积网络实现高效的物体检测，使用位置敏感的得分图解决分类中的平移不变性和物体检测中的平移可变性的问题，可自然地采用全卷积图像分类器骨干网进行物体检测，以101层残差网络(ResNet)在PASCAL VOC数据集上取得83.6%mAP的竞争性结果，测试时间为每张图像170ms，比Faster R-CNN快2.5-20倍。

基于区域全卷积网络的物体检测