Contacts

Identifiers and Keywords

ANZLIC Id

ANZVI0803002648 

Jurisdiction

Victoria 

Topic category

• Imagery base maps earth cover

Resource Constraints

Use limitation

VicMap Digital Image products are provided under the terms and conditions of a licence. 

Classification

Limited Distribution  

Other Dataset Details

Date ( Revision )

2008-12-18

Status

Completed  

Purpose

Vicmap Image SPOT MOSAIC 2001 B&W will be useful as a backdrop for many data visualisation purposes including map production, spatial and thematic interrogation of vector datasets and in presentation and demonstration material. It will be useable at scales of 1:25,000 and smaller. Additionally, Vicmap Image SPOT MOSAIC 2001 B&W can be used for visual interpretation of land cover features. Vicmap Image SPOT MOSAIC 2001 B&W is not be applicable for digital classification purposes, as the digital values have been modified for visual appeal. For any such requirements, the raw component imagery should be used. 

Format

1 Band Geo-Tiff Header files for ESRI products and Mapinfo also supplied. 3 

Supplemental Information

Relationship to other Datasets: Vicmap Imagery SPOT Mosaic 2001 B&W is be an updated version of the existing image catalogue images currently provided in the NRE Corporate Geospatial Data Library. Related Documents: VMDIProductDescript4c.doc. - VicMap Digital Image Product Description 

Maintenance and update frequency

As needed  

Spatial

Spatial representation type

Grid  

Description

General - Victoria 

N

S

E

W

Temporal

Begin date

2000-12-01 

End date

2002-03-30 

Resolution

Horizontal Accuracy

10m  

Quality

Conceptual Consistency

Land cover features across the component images have generally been colour-balanced and matched to each other so that a consistent appearance is achieved across the State. In general, forest and tree cover is represented as dark pixels and dry pasture and soils appear light grey to white in colour. 

Missing Data

Statewide coverage is achieved by mosaicing SPOT Panchromatic/Monochramatic images. 

Attribute Quality

Land cover features across the component images have generally been colour-balanced and matched to each other so that a consistent appearance is achieved across the State. In general, forest and tree cover is represented as dark pixels and dry pasture and soils appear light grey to white in colour. 

Positional Accuracy

All component images used in Vicmap Imagery mosaics are georeferenced to the Vicmap Transport - Roads network using an average of twenty evenly spread control points per image. Additionally, component images over the eastern and southern Victorian highlands have been georeferenced using elevation models from the Vicmap Elevation data set. This ensures that Vicmap Imagery mosaics are equally as accurate in high relief terrain as they are on flat terrain. The spatial accuracy of the Vicmap Imagery mosaics is dependant on the accuracy of the Vicmap Transport - Roads network, the accuracy of Vicmap Elevation used in orthorectifications, and the precision with which control points are collected. Individual and average control point root mean square (RMS) errors for each component image are required to be less than or equal to one and half pixels, or fifteen metres. This is usually achieved for all component images with most average control point RMS errors falling under fifteen metres. In general, ninety percent of all Vicmap Transport - Roads should fall within plus or minus 30 metres of Vicmap Imagery. 

Lineage

Description

The process of creating a seamless mosaic from images of different dates requires that the images be enhanced. Image enhancement helps ensure that like features have the same appearances across all images. However, the process may generalise the clarity of some features, as well as increase the sharpness of other features. The process of image enhancement aims to strike a balance between the optimum representation of the major land cover types across the State. 

Statement

Dataset Source: The source SPOT Panchromatic/Monochromatic images were purchased from ACRES via SPOT Imaging Services. The product name for the imagery purchased from ACRES is Level 1A (Path Image) or ortho-corrected. The product name represents the level of radiometric and geometric processing performed by ACRES on the data. The Level 1A, has been radiometrically corrected. Ortho-corrected have undergone radiometric and geometric correction utilising ground control points and a DEM. Dataset Originality: Derived 

About the Metadata Record

Metadata identifier

urn:uuid / 8199e6aa-9d2f-565f-b459-51a2244af76d