Contacts

Identifiers and Keywords

ANZLIC Id

ANZVI0803009756 

Jurisdiction

Victoria 

Topic category

• Elevation
• Environment
• Geoscientific information

Resource Constraints

Use limitation

Vicmap Elevation LiDAR Points are subject to licensed use. Data Access License Agreements (DALA) are used to provide the terms and conditions of use, including license fees determined by the coverage and extent of the data purchased. Commercial use licenses may also be negotiated with businesses wishing to become a licensed Value-Added Reseller (VAR) or licensed Data Service Provider (DSP). VARs and DSPs offer data ordering and sale services for Vicmap LIDAR DEM datasets. VARs and DSPs offer data ordering and sale services for Vicmap LIDAR DEM datasets. 

Classification

Unclassified  

Other Dataset Details

Date ( Revision )

2023-03-07

Status

Completed  

Purpose

The Vicmap LiDAR Points collection contains high accuracy, LiDAR derived point cloud datasets designed for many and varied applications including: generation of surface datasets such as terrain models to support 3D and digital twin environments, Canopy Height Models (CHM) and Digital Surface Models (DSM). Increasingly, LiDAR point clouds are being for feature extraction including trees and buildings with precise heights and for evaluating slopes and aspects for geolocating infrastructure and services. 

Format

Ranging from Ascii Text, LAS and LAZ 

Supplemental Information

Relationship to other Datasets: ANZVI0803002639 Related Documents: Please see Vicmap Elevation LiDAR Points Collection product description for more detailed information on this product. This can be found on the Vicmap Elevation Webpage. https://www.land.vic.gov.au/maps-and-spatial/spatial-data/vicmap-catalogue 

Maintenance and update frequency

Irregular  

Spatial

Spatial representation type

Vector  

Description

General - Victoria 

Reference system identifier

28355

N

S

E

W

Temporal

Begin date

2007-04-24 

End date

now  

Quality

Conceptual Consistency

The LiDAR DEM datasets are all consistent in their data representation of AHD. As described, variations exist in resolution and vertical accuracy. Additionally, there will be variation in the degree to which older datasets have been hydro flattened and bridges treated, as surface modelling improvements have evolved over time. 

Missing Data

The collection covers approximately 60% of the land area of Victoria and approximately 99% of the populated areas. As an expanding collection, coverage continues to grow in temporal and spatial terms as new datasets are added. Completeness Verification: Each dataset in the collection has been verified for conformity with the vertical accuracy specifications for the LiDAR survey under which the data collected. Vertical accuracy requirements vary between projects from +/-10cm RMSE to +/-50cm RMSE. 

Excess Data

Point classes used in Vicmap LiDAR Points datasets are based on the Australian Intergovernmental Committee for Survey and Mapping (ICSM) LiDAR classification schema. These classes are described in Table 2. Not all classes in the schema have been equally applied across all datasets in the Collection. The designation of classes used in a dataset has always been subject to the specific project requirements of the LiDAR survey and these have not always been the same across projects from which the Collection derives. However, in general, it is true that early Vicmap LiDAR Points datasets will have a lower level of classification detail and thematic accuracy than later datasets. The improvement in classification detail and accuracy in more recent datasets is governed by several interconnected factors. Sensor and positioning technologies have improved over time delivering higher point densities, improved positional representation of points and greater definition of landscape and built features. Improved feature representation allows automated classification algorithms to be more successfully applied across a broader range of classes, reducing the amount of manual editing required and reducing cost. 

Attribute Quality

As the LiDAR DEMs represent the bare earth ground surface, the attribution of the dataset is reflected in the vertical elevation values of the dataset. In this sense, the attribute accuracy is commensurate with the vertical accuracy of the surface which ranges between +/- 10cm RMSE and +/- 50cm RMSE for different datasets in the collection. Vicmap Elevation LiDAR DEMs are most correct when used in their native datums and projections. Transforming and reprojecting DEMs may alter and reduce the fidelity of the elevation values for the transformed or reprojected coordinate. 

Positional Accuracy

Horizontal Accuracy is greater than or equal to +/- 30cm RMSE All LiDAR surveys from which the LiDAR DEM datasets are derived are rated at +/-30cm RMSE horizontal accuracy. Greater horizontal accuracies are now achievable and have been demonstrated in the more recent LiDAR surveys that have contributed LiDAR DEM datasets. Vertical Accuracy ranges between +/- 10cm RMSE and +/- 50cm RMSE Vertical accuracy has historically been a commonly varied LiDAR survey specification. Within the LiDAR DEMs collection, vertical accuracy ranges from +/-50cm RMSE for some of the older datasets to +/-10cm for later datasets. The increase in vertical accuracy is due to improved sensor technology as well as better positioning and aerial survey inertial management technology. 

Lineage

Description

Following airborne LiDAR survey, production methods for generation of point cloud datasets broadly follow a generic processing workflow, although the implementation of some of these stages may vary between commercial suppliers. 1. GNSS/INS Trajectory Processing 2. LiDAR strip alignment 3. LiDAR adjustment to AHD 4. LiDAR classification The surface models exclude road and rail bridges as well as major culverts. If these features were incorrectly classified as LiDAR ground points and automatically included in the DEM, they are subsequently edited out of the model in a manner that ensures the underlaying terrain is continuous and not left as a gap or void in the surface. 

Statement

Dataset Source: Vicmap LiDAR Points derive from LiDAR survey projects undertaken through the States Coordinated Imagery Program (CIP). LiDAR surveys are conducted on behalf of the State by commercial aerial survey companies that have qualified for the relevant State services panels. Acquisition planning is driven by purchase partner investment in the CIP program and is implemented in an on-demand basis. Aerial survey most often occurs as a single project achievable within one flying season by a single commercial supplier. As investment and funding allows, larger capture programs may occur that span multiple flying seasons and require multiple commercial suppliers to complete. LiDAR survey within Victoria is achievable throughout the whole calendar year, however most data capture has been conducted during the spring, summer, and autumn seasons (November through to May). Dataset Originality: Primary 

About the Metadata Record

Metadata identifier

urn:uuid / 6b117598-ba99-5b90-bda7-e0a0d800b26f