TrackFormer: Multi-Object Tracking with Transformers

This repository provides the official implementation of the TrackFormer: Multi-Object Tracking with Transformers paper by Tim Meinhardt, Alexander Kirillov, Laura Leal-Taixe and Christoph Feichtenhofer. The codebase builds upon DETR, Deformable DETR and Tracktor.

Abstract

The challenging task of multi-object tracking (MOT) requires simultaneous reasoning about track initialization, identity, and spatiotemporal trajectories. We formulate this task as a frame-to-frame set prediction problem and introduce TrackFormer, an end-to-end MOT approach based on an encoder-decoder Transformer architecture. Our model achieves data association between frames via attention by evolving a set of track predictions through a video sequence. The Transformer decoder initializes new tracks from static object queries and autoregressively follows existing tracks in space and time with the new concept of identity preserving track queries. Both decoder query types benefit from self- and encoder-decoder attention on global frame-level features, thereby omitting any additional graph optimization and matching or modeling of motion and appearance. TrackFormer represents a new tracking-by-attention paradigm and yields state-of-the-art performance on the task of multi-object tracking (MOT17) and segmentation (MOTS20).

TrackFormer casts multi-object tracking as a set prediction problem performing joint detection and tracking-by-attention. The architecture consists of a CNN for image feature extraction, a Transformer encoder for image feature encoding and a Transformer decoder which applies self- and encoder-decoder attention to produce output embeddings with bounding box and class information.

Installation

We refer to our docs/INSTALL.md for detailed installation instructions.

Train TrackFormer

We refer to our docs/TRAIN.md for detailed training instructions.

Evaluate TrackFormer

In order to evaluate TrackFormer on a multi-object tracking dataset, we provide the src/track.py script which supports several datasets and splits interchangle via the dataset_name argument (See src/datasets/tracking/factory.py for an overview of all datasets.) The default tracking configuration is specified in cfgs/track.yaml. To facilitate the reproducibility of our results, we provide evaluation metrics for both the train and test set.

MOT17

Private detections

python src/track.py with reid

MOT17	MOTA	IDF1	MT	ML	FP	FN	ID SW.
Train	68.1	67.6	816	207	33549	71937	1935
Test	65.0	63.9	1074	324	70443	123552	3528

Public detections (DPM, FRCNN, SDP)

python src/track.py with \
    reid \
    public_detections=min_iou_0_5 \
    obj_detect_checkpoint_file=models/mots20_train_masks/checkpoint.pth

MOT17	MOTA	IDF1	MT	ML	FP	FN	ID SW.
Train	67.2	66.9	663	294	14640	94122	1866
Test	62.5	60.7	702	632	32828	174921	3917

MOTS20

python src/track.py with \
    dataset_name=MOTS20-ALL \
    obj_detect_checkpoint_file=models/mots20_train_masks/checkpoint.pth

Our tracking script only applies MOT17 metrics evaluation but outputs MOTS20 mask prediction files. To evaluate these download the official MOTChallengeEvalKit.

MOTS20	sMOTSA	IDF1	FP	FN	IDs
Train	--	--	--	--	--
Test	54.9	63.6	2233	7195	278

Demo

To facilitate the application of TrackFormer, we provide a demo interface which allows for a quick processing of a given video sequence.

ffmpeg -i data/snakeboard/snakeboard.mp4 -vf fps=30 data/snakeboard/%06d.png

python src/track.py with \
    dataset_name=DEMO \
    data_root_dir=data/snakeboard \
    output_dir=data/snakeboard \
    write_images=pretty

Publication

If you use this software in your research, please cite our publication:

@InProceedings{meinhardt2021trackformer,
    title={TrackFormer: Multi-Object Tracking with Transformers},
    author={Tim Meinhardt and Alexander Kirillov and Laura Leal-Taixe and Christoph Feichtenhofer},
    year={2022},
    month = {June},
    booktitle = {The IEEE Conference on Computer Vision and Pattern Recognition (CVPR)},
}

vvvityaaa/trackformer