Deep convolutional neural networks for pedestrian detection with skip pooling

Abstract

With the big success of deep convolutional neural networks (CNN) in image classification task, many proposal based networks are proposed to detect given objects in an image. Faster R-CNN is such a network that uses a region proposal network (RPN) to generate nearly cost-free region proposals, which has shown excellent performance in ILSVRC and MS COCO datasets. However, Faster R-CNN does not behave so well for the task of pedestrian detection since the images in popular pedestrian detection datasets have more complicated background and contain a lot of small foreground objects. In this work, we leverage the RPN architecture of Faster R-CNN and extend it to a multi-layer version combined with skip pooling to tackle the pedestrian detection problem. Skip pooling is a kind of network connection that combines multiple ROI pooling results from lower layers to form a single input to a higher layer while bypassing intermediate layers. We comprehensively evaluate our network, referred to as SP-CNN, on the Caltech pedestrian detection benchmark and KITTI object detection benchmark. Our method achieves state-of-the-art accuracy on Caltech dataset and presents a comparable result on KITTI dataset while maintaining a good speed.