ChangeSim

Notes on the Dataset

  • RGBD data and poses are available for all runs. However, for the Ref_test sequences, the trajectory.txt files contain more or less entries than there are images available. It is unclear how the poses are to be synced with the image data as no timestamps are provided.
  • The depth images contain banding artifacts (probably from quantization - the images have only one 8 bit channel) that make an accurate reconstruction difficult.
  • While reconstruction from the depth images seems to be difficult, for the query epochs, point cloud reconstructions are available. For the reference epochs, point clouds can be exported from the RTAB-Map database (using the RTAB-Map database viewer). For this, we used a 20m depth limit and removed duplicate points.
  • The dataset can be considered to have 4 epochs per scene - the first and second between which actual changes happen, and the two additional runs for dark and dust, for which only appearance changes happened.
  • While the sequence number generally corresponds to the trajectory followed, Query_Seq_0_dark seems to follow another path than the other runs in Seq_0.

Detailed Information

General Information
NameChangeSim
Release Year2021
Terms of UseUnclear
Access RequirementsNone
Dataset Size167.6 GB | Partial download is possible, i.e. the data is split into several files (e.g., epochs or data types)
DocumentationIn-depth documentation of acquisition and characteristics of the dataset, e.g., via an explicit dataset paper or a comprehensive multi-page metadata document
CodeYes
ApplicationsBuilt environment change detection and classification
Detailed ApplicationsScene change detection in industrial indoor environments
Acquisition
Number of Scenes10
Number of Epochs per Scene (minimum)4
Number of Epochs per Scene (median)4
Number of Epochs per Scene (maximum)4
General Scene TypeIndoor
Specific Scene TypeWarehouse
LocationUnclear
Acquisition TypeDepth camera mounted on vehicle | Synthetic scan
Acquisition DeviceUnreal Engine 4 Renderer
Acquisition PlatformSimulated (drone)
Scan IntervalUndefined
Acquisition Months
Representation
Data RepresentationUnstructured, globally aligned (e.g., point cloud or ray cloud) | Structured, local (e.g., RGBD or range images with poses (and intrinsics)
Specific Data RepresentationPoint cloud | Color and depth images
File Format/EncodingPLY | rtabmap.db
Raw DataRGBD
Additional Data-
Coordinate Systemm
Quality and Usability
RegistrationCoarsely registered
Number of Partial Epochs-
Unusable Data Reason-
SplitsYes
Per-Point Attributes
Intensity/ReflectivityNo
ColorYes
Semantic Labels24 | The labels can be computed from other data/mapped to the point cloud, i.e., it can not trivially be done during point cloud construction
Instance LabelsNo
Change Labels5 | The labels can be computed from other data/mapped to the point cloud, i.e., it can not trivially be done during point cloud construction (at least not for all epochs)
Statistics
Number of Points per Epoch (minimum)299K
Number of Points per Epoch (median)5M
Number of Points per Epoch (maximum)545M
Avg. Point Spacing (minimum)2.7mm
Avg. Point Spacing (median)1.7cm
Avg. Point Spacing (maximum)2.5cm
Avg. Change Points per Epoch8.18%

Paper Reference 1

@inproceedings{park2021datasetchangesim,
    author = {Jin-Man Park and
                  Jae-Hyuk Jang and
                  Sahng-Min Yoo and
                  Sun-Kyung Lee and
                  Ue-Hwan Kim and
                  Jong-Hwan Kim},
    title = {ChangeSim: Towards End-to-End Online Scene Change Detection in Industrial
                  Indoor Environments},
    booktitle = {IEEE/RSJ International Conference on Intelligent Robots and Systems,
                  IROS},
    pages = {8578--8585},
    year = {2021},
    doi = {10.1109/IROS51168.2021.9636350},
}