# Cityscapes VPS

This dataset is derived from the videos in the *validation* split of the Cityscapes[^1] dataset.
It aggregates the images and metadata from Cityscapes[^1], Cityscapes-VPS[^2] and Cityscapes-DVPS[^3] into a single structured format. 
This comprehensive derivative was created out of the need for a batteries-included variant of the dataset for academic purposes.
Specifically, joining samples from the individual datasets in their original structure (each is organized differently) involves a significant amount of boilerplate code. 

[^1]: `Cordts et al., “The Cityscapes Dataset for Semantic Urban Scene Understanding” (CVPR 2016)`

[^2]: `Kim et al., "Video Panoptic Segmentation" (CVPR 2020)`

[^3]: `Qiao et al., "Learning Visual Perception with Depth-aware Video Panoptic Segmentation" (CVPR 2021)`


This dataset is relevant to computer vision research areas such as:

- Segmentation
- Depth estimation
- Autonomous driving
- Video understanding

## Overview
The following variables are included.

1. **Images.** The input data captured by the left camera from Cityscapes[^1], in 8-bit format. Every sequence has 30 frames.
2. **Segmentation labels.** Derived from Cityscapes[^1] and Cityscapes-DVPS[^3], these labels provide detailed semantic segmentation and instance segmentation information for 6 frames of every sequence.
3. **Depth maps.** Improved depth information from Cityscapes-DVPS[^3], offering enhanced quality over the disparity package from Cityscapes[^1], provided for the same samples as the segmentation labels above.
4. **Camera calibrations.** Includes the intrinsic and extrinsic parameters provided by Cityscapes[^1] for each sequence.
5. **Vehicle odometry.** Odometry data for each frame, a subset of those provided in Cityscapes[^1].

Files are grouped by split, sequence and frame.
This leads to the following structure:
```text
data
    train
        000000
            000000.image.png
            000000.panoptic.png
            000000.depth.png
            000000.vehicle.json
            000000.timestamp.txt
            000000.camera.json
            000001.image.png
            000001.panoptic.png
            000001.depth.png
            000001.vehicle.json
            000001.timestamp.txt
            000001.camera.json
            ...
        000001
            ...
    val
        000000
            ...
        000001
            ....
    test
        000000
            ...
        000001
            ....

```

The `data` directory in this repository only contains the segmentation and depth map annotations.
The remaining data should be downloaded from official sources using the provided preparation script.


## Preparation

1. Install the [Cityscapes developer kit](https://github.com/mcordts/cityscapesScripts) using `pip`.

```bash
python -m pip install cityscapesscripts
```

2. Run the preparation script provided in this repository. 
   Note that this may prompt your [Cityscapes account](https://cityscapes-dataset.com/login/) login credentials.

```bash
python scripts/download.py downloads data manifest.csv
```

3. Remove the downloaded Cityscapes archive files to save disk space (optional).

```bash
rm -r downloads
```


## License

Please refer to the Cityscapes license for more details.


## Citation

If you use this dataset in your research, please cite the original 
[Cityscapes](https://cityscapes-dataset.com), 
[Cityscapes-VPS](https://github.com/mcahny/vps), and
[Cityscapes-DVPS](https://github.com/joe-siyuan-qiao/ViP-DeepLab) datasets.