ByteTrack

ByteTrack is a simple, fast and strong multi-object tracker.

ByteTrack: Multi-Object Tracking by Associating Every Detection Box

Yifu Zhang, Peize Sun, Yi Jiang, Dongdong Yu, Zehuan Yuan, Ping Luo, Wenyu Liu, Xinggang Wang

arXiv 2110.06864

Demo Links

Google Colab demo	Huggingface Demo	Original Paper: ByteTrack
		arXiv 2110.06864

• Integrated to Huggingface Spaces with Gradio.

Abstract

Multi-object tracking (MOT) aims at estimating bounding boxes and identities of objects in videos. Most methods obtain identities by associating detection boxes whose scores are higher than a threshold. The objects with low detection scores, e.g. occluded objects, are simply thrown away, which brings non-negligible true object missing and fragmented trajectories. To solve this problem, we present a simple, effective and generic association method, tracking by associating every detection box instead of only the high score ones. For the low score detection boxes, we utilize their similarities with tracklets to recover true objects and filter out the background detections. When applied to 9 different state-of-the-art trackers, our method achieves consistent improvement on IDF1 scores ranging from 1 to 10 points. To put forwards the state-of-the-art performance of MOT, we design a simple and strong tracker, named ByteTrack. For the first time, we achieve 80.3 MOTA, 77.3 IDF1 and 63.1 HOTA on the test set of MOT17 with 30 FPS running speed on a single V100 GPU.

Tracking performance

Results on MOT challenge test set

Dataset	MOTA	IDF1	HOTA	MT	ML	FP	FN	IDs	FPS
MOT17	80.3	77.3	63.1	53.2%	14.5%	25491	83721	2196	29.6
MOT20	77.8	75.2	61.3	69.2%	9.5%	26249	87594	1223	13.7

Visualization results on MOT challenge test set

Installation

1. Installing on the host machine

Step1. Install ByteTrack.

git clone https://github.com/ifzhang/ByteTrack.git
cd ByteTrack
pip3 install -r requirements.txt
python3 setup.py develop

Step2. Install pycocotools.

pip3 install cython; pip3 install 'git+https://github.com/cocodataset/cocoapi.git#subdirectory=PythonAPI'

Step3. Others

pip3 install cython_bbox

2. Docker build

docker build -t bytetrack:latest .

# Startup sample
mkdir -p pretrained && \
mkdir -p YOLOX_outputs && \
xhost +local: && \
docker run --gpus all -it --rm \
-v $PWD/pretrained:/workspace/ByteTrack/pretrained \
-v $PWD/datasets:/workspace/ByteTrack/datasets \
-v $PWD/YOLOX_outputs:/workspace/ByteTrack/YOLOX_outputs \
-v /tmp/.X11-unix/:/tmp/.X11-unix:rw \
--device /dev/video0:/dev/video0:mwr \
--net=host \
-e XDG_RUNTIME_DIR=$XDG_RUNTIME_DIR \
-e DISPLAY=$DISPLAY \
--privileged \
bytetrack:latest

Data preparation

Download MOT17, MOT20, CrowdHuman, Cityperson, ETHZ and put them under /datasets in the following structure:

datasets
   |——————mot
   |        └——————train
   |        └——————test
   └——————crowdhuman
   |         └——————Crowdhuman_train
   |         └——————Crowdhuman_val
   |         └——————annotation_train.odgt
   |         └——————annotation_val.odgt
   └——————MOT20
   |        └——————train
   |        └——————test
   └——————Cityscapes
   |        └——————images
   |        └——————labels_with_ids
   └——————ETHZ
            └——————eth01
            └——————...
            └——————eth07

Then, you need to turn the datasets to COCO format and mix different training data:

cd <ByteTrack_HOME>
python3 tools/convert_mot17_to_coco.py
python3 tools/convert_mot20_to_coco.py
python3 tools/convert_crowdhuman_to_coco.py
python3 tools/convert_cityperson_to_coco.py
python3 tools/convert_ethz_to_coco.py

Before mixing different datasets, you need to follow the operations in mix_xxx.py to create a data folder and link. Finally, you can mix the training data:

cd <ByteTrack_HOME>
python3 tools/mix_data_ablation.py
python3 tools/mix_data_test_mot17.py
python3 tools/mix_data_test_mot20.py

Model zoo

Ablation model

Train on CrowdHuman and MOT17 half train, evaluate on MOT17 half val

Model	MOTA	IDF1	IDs	FPS
ByteTrack_ablation [google], [baidu(code:eeo8)]	76.6	79.3	159	29.6

MOT17 test model

Train on CrowdHuman, MOT17, Cityperson and ETHZ, evaluate on MOT17 train.

• Standard models

Model	MOTA	IDF1	IDs	FPS
bytetrack_x_mot17 [google], [baidu(code:ic0i)]	90.0	83.3	422	29.6
bytetrack_l_mot17 [google], [baidu(code:1cml)]	88.7	80.7	460	43.7
bytetrack_m_mot17 [google], [baidu(code:u3m4)]	87.0	80.1	477	54.1
bytetrack_s_mot17 [google], [baidu(code:qflm)]	79.2	74.3	533	64.5

• Light models

Model	MOTA	IDF1	IDs	Params(M)	FLOPs(G)
bytetrack_nano_mot17 [google], [baidu(code:1ub8)]	69.0	66.3	531	0.90	3.99
bytetrack_tiny_mot17 [google], [baidu(code:cr8i)]	77.1	71.5	519	5.03	24.45

MOT20 test model

Train on CrowdHuman and MOT20, evaluate on MOT20 train.

Model	MOTA	IDF1	IDs	FPS
bytetrack_x_mot20 [google], [baidu(code:3apd)]	93.4	89.3	1057	17.5

Training

The COCO pretrained YOLOX model can be downloaded from their model zoo. After downloading the pretrained models, you can put them under /pretrained.

• Train ablation model (MOT17 half train and CrowdHuman)

cd <ByteTrack_HOME>
python3 tools/train.py -f exps/example/mot/yolox_x_ablation.py -d 8 -b 48 --fp16 -o -c pretrained/yolox_x.pth

• Train MOT17 test model (MOT17 train, CrowdHuman, Cityperson and ETHZ)

cd <ByteTrack_HOME>
python3 tools/train.py -f exps/example/mot/yolox_x_mix_det.py -d 8 -b 48 --fp16 -o -c pretrained/yolox_x.pth

• Train MOT20 test model (MOT20 train, CrowdHuman)

For MOT20, you need to clip the bounding boxes inside the image.

Add clip operation in line 134-135 in data_augment.py, line 122-125 in mosaicdetection.py, line 217-225 in mosaicdetection.py, line 115-118 in boxes.py.

cd <ByteTrack_HOME>
python3 tools/train.py -f exps/example/mot/yolox_x_mix_mot20_ch.py -d 8 -b 48 --fp16 -o -c pretrained/yolox_x.pth

• Train custom dataset

First, you need to prepare your dataset in COCO format. You can refer to MOT-to-COCO or CrowdHuman-to-COCO. Then, you need to create a Exp file for your dataset. You can refer to the CrowdHuman training Exp file. Don’t forget to modify get_data_loader() and get_eval_loader in your Exp file. Finally, you can train bytetrack on your dataset by running:

cd <ByteTrack_HOME>
python3 tools/train.py -f exps/example/mot/your_exp_file.py -d 8 -b 48 --fp16 -o -c pretrained/yolox_x.pth

Tracking

• Evaluation on MOT17 half val

Run ByteTrack:

cd <ByteTrack_HOME>
python3 tools/track.py -f exps/example/mot/yolox_x_ablation.py -c pretrained/bytetrack_ablation.pth.tar -b 1 -d 1 --fp16 --fuse

You can get 76.6 MOTA using our pretrained model.

Run other trackers:

python3 tools/track_sort.py -f exps/example/mot/yolox_x_ablation.py -c pretrained/bytetrack_ablation.pth.tar -b 1 -d 1 --fp16 --fuse
python3 tools/track_deepsort.py -f exps/example/mot/yolox_x_ablation.py -c pretrained/bytetrack_ablation.pth.tar -b 1 -d 1 --fp16 --fuse
python3 tools/track_motdt.py -f exps/example/mot/yolox_x_ablation.py -c pretrained/bytetrack_ablation.pth.tar -b 1 -d 1 --fp16 --fuse

• Test on MOT17

Run ByteTrack:

cd <ByteTrack_HOME>
python3 tools/track.py -f exps/example/mot/yolox_x_mix_det.py -c pretrained/bytetrack_x_mot17.pth.tar -b 1 -d 1 --fp16 --fuse
python3 tools/interpolation.py

Submit the txt files to MOTChallenge website and you can get 79+ MOTA (For 80+ MOTA, you need to carefully tune the test image size and high score detection threshold of each sequence).

• Test on MOT20

We use the input size 1600 x 896 for MOT20-04, MOT20-07 and 1920 x 736 for MOT20-06, MOT20-08. You can edit it in yolox_x_mix_mot20_ch.py

Run ByteTrack:

cd <ByteTrack_HOME>
python3 tools/track.py -f exps/example/mot/yolox_x_mix_mot20_ch.py -c pretrained/bytetrack_x_mot20.pth.tar -b 1 -d 1 --fp16 --fuse --match_thresh 0.7 --mot20
python3 tools/interpolation.py

Submit the txt files to MOTChallenge website and you can get 77+ MOTA (For higher MOTA, you need to carefully tune the test image size and high score detection threshold of each sequence).

Applying BYTE to other trackers

See tutorials.

Combining BYTE with other detectors

Suppose you have already got the detection results ‘dets’ (x1, y1, x2, y2, score) from other detectors, you can simply pass the detection results to BYTETracker (you need to first modify some post-processing code according to the format of your detection results in byte_tracker.py):

from yolox.tracker.byte_tracker import BYTETracker
tracker = BYTETracker(args)
for image in images:
   dets = detector(image)
   online_targets = tracker.update(dets, info_imgs, img_size)

You can get the tracking results in each frame from ‘online_targets’. You can refer to mot_evaluators.py to pass the detection results to BYTETracker.

Demo

cd <ByteTrack_HOME>
python3 tools/demo_track.py video -f exps/example/mot/yolox_x_mix_det.py -c pretrained/bytetrack_x_mot17.pth.tar --fp16 --fuse --save_result

Deploy

1. ONNX export and ONNXRuntime
2. TensorRT in Python
3. TensorRT in C++
4. ncnn in C++

Citation

@article{zhang2021bytetrack,
  title={ByteTrack: Multi-Object Tracking by Associating Every Detection Box},
  author={Zhang, Yifu and Sun, Peize and Jiang, Yi and Yu, Dongdong and Yuan, Zehuan and Luo, Ping and Liu, Wenyu and Wang, Xinggang},
  journal={arXiv preprint arXiv:2110.06864},
  year={2021}
}

Acknowledgement

A large part of the code is borrowed from YOLOX, FairMOT, TransTrack and JDE-Cpp. Many thanks for their wonderful works.