Contacts

 

Identifiers and Keywords

ANZLIC Id

ANZVI0008102531 

Topic category

• Elevation

 

Resource Constraints

Use limitation

General 

Classification

Unclassified  

 

Other Dataset Details

Format

LAS 1.3 

 

Spatial

Spatial representation type

Point Cloud  

Reference system identifier

MGA Zone 55 GDA94

 

Resolution

Horizontal Accuracy

0.3m  

Vertical Accuracy

0.1m  

 

Quality

Conceptual Consistency

Accuracy of the ground surface under dense canopy may be reduced due to diminished returns. Laser accuracy at swath edges may be reduced. Classification algorithms have been tailored for common terrain/vegetation combinations across the project area. Classification accuracy and ground definition may be less accurate in uncommon or mixed terrain/vegetation/land use combinations. This data has been classified to an ICSM level 2 standard where there is an emphasis on ground classification accuracy only. 

Missing Data

The point cloud data is complete for the defined project extent. Gaps may occur due to diminished returns over water, under canopy and on materials with low laser reflectivity, such as black roofing or swimming pools. 

 

Lineage

Description

An instrument calibration issue was encountered with the LiDAR system during initial pre-processing. The issue was caused by an internal calibration error between channel 1 and channel 2. It manifests itself by producing a fluctuating, vertical, misalignment between both channels in the range of 0.05 - 0.20m (relative accuracy). It was resolved by an internal calibration correction (provided by sensor manufacturer - Riegl) being applied to all flights of LiDAR data in this project. This delayed production for approximately three weeks. Reduction of the LiDAR data proceeded without any significant problems, Laser strikes were classified into ground and non-ground points using a single algorithm across the project area. Manual checking and editing of the data classification further improved the quality of the terrain model. 

 

Acquisition Date

Begin date

2016-01-11 

End date

2016-01-11 

 

Instrument

Name

Riegl Q1560 

Type

LIDAR 

Platform Type

Aerial 

 

Acquisition Data (Common)

Status

complete  

Assembly

Single  

Tile Size

2 km  

Cloud Cover Percentage

0 

 

Point Cloud Details

Pulse Mode

Multi Pulse 

Scan Rate (Hz)

102Hz  

Scan Frequency (kHz)

330kHz  

Scan Angle (degrees)

60degrees  

Footprint Size (m)

0.33500001m  

Point Density Actual (pts/m2)

0.06points/m2  

Point Spacing Actual (pts/m)

4points/m2  

Ellipsoid Provided

1 

Ellipsoid Vertical Datum

AUSGEOID09  

Ellipsoid Format

LAS 1.3  

Geoid Vertical Datum

AUSGEOID09  

Additional Adjustments

Ground data in this volume has been compared to 270 test points obtained by field survey and assumed to be error-free. The test points were distributed in three groups across the mapping area and located on open clear ground. Comparison of the field test points with elevations interpolated from measured data for the three sites resulted in 0.943, 0.891 & 0.885 RMS (m). The mean difference at each site has been removed from the data. Final accuracy estimates after removing the mean offsets yielded 0.031, 0.032 & 0.016 RMS(m). 

Class Level

2 

Classification Accuracy

98 

Classification

Class Level	Classification Accuracy	Class 0 - Unclassified	Class 1 - Default	Class 2 - Ground	Class 3 - Low Vegetation	Class 4 - Medium Vegetation	Class 5 - High Vegetation	Class 6 - Buildings/Structures	Class 7 - Low/High Points	Class 8 - Model Key Points	Class 9- Water	Class 10 - Bridge	Class 12 - Flightline Overlap Points
2	98	1	1	1	1	1	1	1	1	1	1	1	1

 

Aerial Survey Details

Runs

9 

Run Orientation

NE-SW  

Swath Width

2300 

Side Overlap

20 

Forward Overlap

60 

Flying Height Unit

agl metre  

Flight Height

2000 

 

About the Metadata Record

Metadata identifier

ad0fe145-797a-58bc-94c0-49e8713180ad

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