faster_rcnn

Faster R-CNN

Faster R-CNN: Towards Real-Time Object Detection with Region Proposal Networks

Abstract

State-of-the-art object detection networks depend on region proposal algorithms to hypothesize object locations. Advances like SPPnet and Fast R-CNN have reduced the running time of these detection networks, exposing region proposal computation as a bottleneck. In this work, we introduce a Region Proposal Network (RPN) that shares full-image convolutional features with the detection network, thus enabling nearly cost-free region proposals. An RPN is a fully convolutional network that simultaneously predicts object bounds and objectness scores at each position. The RPN is trained end-to-end to generate high-quality region proposals, which are used by Fast R-CNN for detection. We further merge RPN and Fast R-CNN into a single network by sharing their convolutional features---using the recently popular terminology of neural networks with 'attention' mechanisms, the RPN component tells the unified network where to look. For the very deep VGG-16 model, our detection system has a frame rate of 5fps (including all steps) on a GPU, while achieving state-of-the-art object detection accuracy on PASCAL VOC 2007, 2012, and MS COCO datasets with only 300 proposals per image. In ILSVRC and COCO 2015 competitions, Faster R-CNN and RPN are the foundations of the 1st-place winning entries in several tracks.

Results and Models

Backbone	Style	Lr schd	Mem (GB)	Inf time (fps)	box AP	Config	Download
R-50-C4	caffe	1x	-	-	35.6	config	model | log
R-50-DC5	caffe	1x	-	-	37.2	config	model | log
R-50-FPN	caffe	1x	3.8		37.8	config	model | log
R-50-FPN	pytorch	1x	4.0	21.4	37.4	config	model | log
R-50-FPN (FP16)	pytorch	1x	3.4	28.8	37.5	config	model | log
R-50-FPN	pytorch	2x	-	-	38.4	config	model | log
R-101-FPN	caffe	1x	5.7		39.8	config	model | log
R-101-FPN	pytorch	1x	6.0	15.6	39.4	config	model | log
R-101-FPN	pytorch	2x	-	-	39.8	config	model | log
X-101-32x4d-FPN	pytorch	1x	7.2	13.8	41.2	config	model | log
X-101-32x4d-FPN	pytorch	2x	-	-	41.2	config	model | log
X-101-64x4d-FPN	pytorch	1x	10.3	9.4	42.1	config	model | log
X-101-64x4d-FPN	pytorch	2x	-	-	41.6	config	model | log

Different regression loss

We trained with R-50-FPN pytorch style backbone for 1x schedule.

Backbone	Loss type	Mem (GB)	Inf time (fps)	box AP	Config	Download
R-50-FPN	L1Loss	4.0	21.4	37.4	config	model | log
R-50-FPN	IoULoss			37.9	config	model | log
R-50-FPN	GIoULoss			37.6	config	model | log
R-50-FPN	BoundedIoULoss			37.4	config	model | log

Pre-trained Models

We also train some models with longer schedules and multi-scale training. The users could finetune them for downstream tasks.

Backbone	Style	Lr schd	Mem (GB)	Inf time (fps)	box AP	Config	Download
R-50-C4	caffe	1x	-		35.9	config	model | log
R-50-DC5	caffe	1x	-		37.4	config	model | log
R-50-DC5	caffe	3x	-		38.7	config	model | log
R-50-FPN	caffe	2x	3.7		39.7	config	model | log
R-50-FPN	caffe	3x	3.7		39.9	config	model | log
R-50-FPN	pytorch	3x	3.9		40.3	config	model | log
R-101-FPN	caffe	3x	5.6		42.0	config	model | log
R-101-FPN	pytorch	3x	5.8		41.8	config	model | log
X-101-32x4d-FPN	pytorch	3x	7.0		42.5	config	model | log
X-101-32x8d-FPN	pytorch	3x	10.1		42.4	config	model | log
X-101-64x4d-FPN	pytorch	3x	10.0		43.1	config	model | log

We further finetune some pre-trained models on the COCO subsets, which only contain only a few of the 80 categories.

Backbone	Style	Class name	Pre-traind model	Mem (GB)	box AP	Config	Download
R-50-FPN	caffe	person	R-50-FPN-Caffe-3x	3.7	55.8	config	model | log
R-50-FPN	caffe	person-bicycle-car	R-50-FPN-Caffe-3x	3.7	44.1	config	model | log

Torchvision New Receipe (TNR)

Torchvision released its high-precision ResNet models. The training details can be found on the Pytorch website. Here, we have done grid searches on learning rate and weight decay and found the optimal hyper-parameter on the detection task.

Backbone	Style	Lr schd	Mem (GB)	Inf time (fps)	box AP	Config	Download
R-50-TNR	pytorch	1x	-		40.2	config	model | log

Citation

@article{Ren_2017,
   title={Faster R-CNN: Towards Real-Time Object Detection with Region Proposal Networks},
   journal={IEEE Transactions on Pattern Analysis and Machine Intelligence},
   publisher={Institute of Electrical and Electronics Engineers (IEEE)},
   author={Ren, Shaoqing and He, Kaiming and Girshick, Ross and Sun, Jian},
   year={2017},
   month={Jun},
}