Victorian Spatial Data Directory

2001 SPOT Panchromatic/Monochromatic - Vicmap Imagery (Satellite) (SPOTP-2001VI10/)

Unique Id

ANZVI0803002709

Custodian

Department of Sustainability and Environments

Jurisdiction

Victoria

Description

Abstract

Vicmap Image represents a suite of statewide satellite image mosaic products. The first Vicmap Image product is a Statewide Landsat 7 Enhanced Thematic Mapper (ETM+) mosaic for the summer of 1999/2000, titled Vicmap Image TM7-2000. The second entitled SPOT MOSAIC 2001 BandW is a mosaic of SPOT Panchromatic and Monochromatic images from December 2000 to March 2002.

Vicmap Image SPOT MOSAIC 2001 BandW is a 1-band, 8-bit Geo-TIFF image.

Vicmap Imagery TM7-2000VI30 has a spatial resolution of 30 metres and a nominal usage scale of 1:50,000 or smaller. It provides an excellent representation of tree cover, agricultural land use, the extent of urban area, and water resources in Victoria.

Search Word(s)

PHOTOGRAPHY AND IMAGERY Satellite

Geographic Extent Name(s)

Victoria

Bounding Box

34.0 S

141.0 E

150.2 E

39.2 S

Dataset Currency

Beginning Date

01DEC2000

Ending Date

30MAR2002

Dataset Status

Progress

Complete

Maintenance and Update

As required

Dataset Access

Stored Data Format(s)

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

Available Format Type(s)

- as above

Access Constraints

Not Documented

Data Quality

Lineage

Data Set 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.

Collection Method:

Processing Steps:
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.

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.

Attribute Accuracy

There are no attributes attached to the Vicmap Imagery SPOT Mosaic 2001 BandW. All associated information is provided through the standard NRE metadata protocol.
Generally, the physical size of the features and the spatial resolution of the SPOT sensors determine the clarity and sharpness with which those features can be identified. However, the colour contrast within and the colour balance between images can be manipulated to produce a mosaic that is both visually appealing and thematically rich in content. The level of success in achieving this outcome is subjective.

Logical 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.

Completeness

Contact

Contact Organisation

Department of Sustainability and Environments

Contact Position

Remote Sensing/GIS Analyst, Custodian - Vicmap Imagery and Vegetation

Address

P O Box 500

East Melbourne VIC 3001

Australia

Phone

(03) 8636 2333

Facsimile

(03) 8636 2813

Email Address

john.white@dse.vic.gov.au

Other

Metadata Date

15MAR2004

Additional Metadata