CitySegmentation - Dataset Ninja

Summary #

CitySegmentation is a dataset for instance segmentation, semantic segmentation, and object detection tasks. Possible applications of the dataset could be in the geospatial domain.

The dataset consists of 50 images with 9306 labeled objects belonging to 2 different classes including building and road.

Images in the CitySegmentation dataset have pixel-level instance segmentation annotations. Due to the nature of the instance segmentation task, it can be automatically transformed into a semantic segmentation (only one mask for every class) or object detection (bounding boxes for every object) tasks. All images are labeled (i.e. with annotations). There are no pre-defined train/val/test splits in the dataset. Additionally, images have city tag: Berlin or London. The dataset was released in 2019.

Explore #

CitySegmentation dataset has 50 images. Click on one of the examples below or open "Explore" tool anytime you need to view dataset images with annotations. This tool has extended visualization capabilities like zoom, translation, objects table, custom filters and more. Hover the mouse over the images to hide or show annotations.

Sample annotation mask from CitySegmentation

👀

Have a look at 50 images

View images along with annotations and tags, search and filter by various parameters

Class balance #

There are 2 annotation classes in the dataset. Find the general statistics and balances for every class in the table below. Click any row to preview images that have labels of the selected class. Sort by column to find the most rare or prevalent classes.

Rows 1-2 of 2

Class ㅤ	Images ㅤ	Objects ㅤ	Count on image average	Area on image average
road➔ mask	50	955	19.1	9.83%
building➔ mask	50	8351	167.02	31.78%

Co-occurrence matrix #

Co-occurrence matrix is an extremely valuable tool that shows you the images for every pair of classes: how many images have objects of both classes at the same time. If you click any cell, you will see those images. We added the tooltip with an explanation for every cell for your convenience, just hover the mouse over a cell to preview the description.

Images #

Explore every single image in the dataset with respect to the number of annotations of each class it has. Click a row to preview selected image. Sort by any column to find anomalies and edge cases. Use horizontal scroll if the table has many columns for a large number of classes in the dataset.

Class sizes #

The table below gives various size properties of objects for every class. Click a row to see the image with annotations of the selected class. Sort columns to find classes with the smallest or largest objects or understand the size differences between classes.

Rows 1-2 of 2

Class	Object count	Avg area	Max area	Min area	Min height	Min height	Max height	Max height	Avg height	Avg height	Min width	Min width	Max width	Max width
building mask	8351	0.19%	7.06%	0%	2px	0.06%	2871px	59.81%	164px	4.36%	3px	0.06%	3994px	79.5%
road mask	955	0.52%	14.05%	0%	2px	0.06%	4800px	100%	379px	9.27%	9px	0.18%	5024px	100%

Spatial Heatmap #

The heatmaps below give the spatial distributions of all objects for every class. These visualizations provide insights into the most probable and rare object locations on the image. It helps analyze objects' placements in a dataset.

Objects #

Table contains all 9306 objects. Click a row to preview an image with annotations, and use search or pagination to navigate. Sort columns to find outliers in the dataset.

Rows 1-10 of 9306

Object ID ㅤ	Class ㅤ	Image name click row to open	Image size height x width	Height ㅤ	Height ㅤ	Width ㅤ	Width ㅤ	Area ㅤ
1➔	building mask	london_4_1_raster.png.tiff	3216 x 4288	107px	3.33%	245px	5.71%	0.05%
2➔	building mask	london_4_1_raster.png.tiff	3216 x 4288	51px	1.59%	175px	4.08%	0.03%
3➔	building mask	london_4_1_raster.png.tiff	3216 x 4288	114px	3.54%	353px	8.23%	0.11%
4➔	building mask	london_4_1_raster.png.tiff	3216 x 4288	29px	0.9%	132px	3.08%	0.02%
5➔	building mask	london_4_1_raster.png.tiff	3216 x 4288	377px	11.72%	198px	4.62%	0.13%
6➔	building mask	london_4_1_raster.png.tiff	3216 x 4288	351px	10.91%	638px	14.88%	0.11%
7➔	building mask	london_4_1_raster.png.tiff	3216 x 4288	51px	1.59%	212px	4.94%	0.04%
8➔	building mask	london_4_1_raster.png.tiff	3216 x 4288	127px	3.95%	340px	7.93%	0.21%
9➔	building mask	london_4_1_raster.png.tiff	3216 x 4288	454px	14.12%	903px	21.06%	0.43%
10➔	building mask	london_4_1_raster.png.tiff	3216 x 4288	47px	1.46%	238px	5.55%	0.03%

License #

CitySegmentation is under ODbL v1.0 license.

Source

Citation #

If you make use of the CitySegmentation data, please cite the following reference:

@dataset{CitySegmentation,
  author={},
  title={CitySegmentation},
  year={2019},
  url={https://www.kaggle.com/datasets/cceekkigg/berlin-aoi-dataset}
}

Source

If you are happy with Dataset Ninja and use provided visualizations and tools in your work, please cite us:

@misc{ visualization-tools-for-city-segmentation-dataset,
  title = { Visualization Tools for CitySegmentation Dataset },
  type = { Computer Vision Tools },
  author = { Dataset Ninja },
  howpublished = { \url{ https://datasetninja.com/city-segmentation } },
  url = { https://datasetninja.com/city-segmentation },
  journal = { Dataset Ninja },
  publisher = { Dataset Ninja },
  year = { 2024 },
  month = { jul },
  note = { visited on 2024-07-27 },
}

Download #

Dataset CitySegmentation can be downloaded in Supervisely format:

As an alternative, it can be downloaded with dataset-tools package:

pip install --upgrade dataset-tools

… using following python code:

import dataset_tools as dtools

dtools.download(dataset='CitySegmentation', dst_dir='~/dataset-ninja/')

Make sure not to overlook the python code example available on the Supervisely Developer Portal. It will give you a clear idea of how to effortlessly work with the downloaded dataset.

The data in original format can be downloaded here.

. . .

Disclaimer #

Our gal from the legal dep told us we need to post this:

Dataset Ninja provides visualizations and statistics for some datasets that can be found online and can be downloaded by general audience. Dataset Ninja is not a dataset hosting platform and can only be used for informational purposes. The platform does not claim any rights for the original content, including images, videos, annotations and descriptions. Joint publishing is prohibited.

You take full responsibility when you use datasets presented at Dataset Ninja, as well as other information, including visualizations and statistics we provide. You are in charge of compliance with any dataset license and all other permissions. You are required to navigate datasets homepage and make sure that you can use it. In case of any questions, get in touch with us at hello@datasetninja.com.