Identifiers and Keywords

ANZLIC Id

ANZVI0008107158 

Topic category

• Elevation

Resource Constraints

Use limitation

General 

Classification

Unclassified  

Other Dataset Details

Format

TIFF 

Spatial

Spatial representation type

Grid  

Reference system identifier

MGA Zone 54 GDA2020

Quality

Conceptual Consistency

All raster values are within expected data ranges. 

Missing Data

The raster data set consists of full data tiles (no null space) and the extent and coverage is common with the other datasets in this project. 

Lineage

Description

Digital Elevation Model (DEM) - The DEM was generated from the point cloud (class 2 - Ground). Terrain Grids were derived using LasTools las2dem. This software reads LIDAR points from the LAS/LAZformat, triangulates them temporarily into a TIN, and then rasterises the TIN onto a DEM. Standard linear interpolation is used. Bridge Removal – bridges have been classified and excluded from DEM generation. Additional synthetic points were collected to support the DEM shape when bridges and culverts were removed. These points have only been introduced into the DEM processing, to avoid triangulation across the bridge or culvert. Hydro-flattening was undertaken as per DELWP guidelines. Hydro-flattening features are drawn manually to define the following: Non-tidal water bodies with surface area greater than 625m2 Non-tidal water courses greater than 30m nominal width are hydroflattened as appropriate for the gradient of the river. Braided rivers with shingle beds are treated as ground. Tidal variation – AAM recommend clipping/masking coastal water from the DEM, while retaining all valid offshore rocks and islands. This gives a clean presentation around the coastline and includes all valid ground data. Areas outside the coastal boundary have "no data” value applied to the full tile extents. Hydro Features are drawn with reference to the point cloud and intensity images to define water boundaries and ocean clipping boundaries for tidal water areas. These are used to generate points to fill the water bodies with height extracted from the lowest surrounding ground points. For sloping rivers, a manual approach is required to define cross-sections of river where the gradient changes to apply sloping heights accordingly. Ground classified points, hydro-flattening points and synthetic points for bridge and culvert removal are combined to form the input data for DEM generation using Point to TIN, and TIN to Raster Natural Neighbour interpolation. 

Acquisition Date

Begin date

2022-02-11 

End date

2022-02-12 

Instrument

Name

Optech Galaxy Prime 

Type

LIDAR 

Platform Type

Aerial 

Acquisition Data (Common)

Status

complete  

Assembly

Single  

Tile Size

1 km  

Raster Details

Number of Bands

1 

Band List

1  

Resampling Kernel

Not Entered  

Platform Name

Fixed Wing Aircraft  

Seamlessness

Full  

Rectification Type

Not Entered  

DEM Details

DEM Creator

Supplier  

Aerial Survey Details

Runs

29 

Run Orientation

N-S  

Swath Width

1000 

Flying Height Unit

agl metre  

Flight Height

1000 

About the Metadata Record

Metadata identifier

2e882e6b-5c5f-5fd2-b25f-ca876d097417

Resource Type

Dataset  

Date info ( Revision )

2023-03-22T00:22:23

Standard Name

ISO 19115-3:2018 

Profile Name

DELWP Profile 

Profile Version

Version 1 

Profile Date

2019-05-24  

Metadata Constraints

Classification

Unclassified