RETIRED Pixel Quality 25 v. 2

<b>This record was retired 29/03/2022 with approval from S.Oliver as it has been superseded by eCat 132317 GA Landsat 8 OLI/TIRS Analysis Ready Data Collection 3</b>


The PQ25 product facilitates interpretation and processing of Surface Reflectance (SR-N/NT), Fractional Cover 25 (FC25) and all derivative products.

PQ25 is an assessment of each image pixel to determine if it is an unobscured, unsaturated observation of the Earth's surface and also whether the pixel is represented in each spectral band. The PQ product allows users to produce masks which can be used to exclude pixels which don't meet their quality criteria from analysis . The capacity to automatically exclude such pixels is essential for emerging multi-temporal analysis techniques that make use of every quality assured pixel within a time series of observations.

Users can choose to process only land pixels, or only sea pixels depending on their analytical requirements, leading to enhanced computationally efficient.

Simple

Identification info

Date (Publication)
2016-06-17T00:00:00
Date (Revision)
2017-11-09T05:14:00
Date (Revision)
2018-06-14T05:15:21
Date (Superseded)
2022-03-29
Edition

1

Citation identifier
Geoscience Australia Persistent Identifier/https://pid.geoscience.gov.au/dataset/ga/102290

Cited responsible party
Role Organisation / Individual Name Details
Owner

Commonwealth of Australia (Geoscience Australia)

 Voice
Status
Superseded
Point of contact
Role Organisation / Individual Name Details
Owner

Commonwealth of Australia (Geoscience Australia)

 Voice
Custodian

Commonwealth of Australia (Geoscience Australia)

 Voice
Point of contact

Commonwealth of Australia (Geoscience Australia)

 Voice
Point of contact

Commonwealth of Australia (Geoscience Australia)

 Voice
Point of contact

Commonwealth of Australia (Geoscience Australia)

 Voice
Point of contact

Commonwealth of Australia (Geoscience Australia)

 Voice
Point of contact

Commonwealth of Australia (Geoscience Australia)

 Voice
Point of contact

Commonwealth of Australia (Geoscience Australia)

 Voice
Topic category
  • Geoscientific information

Extent

N
S
E
W


Temporal extent

Time period
2016-09-13
Maintenance and update frequency
As needed
Keywords

  • NCI

Keywords

  • Satellite imagery

Keywords

  • Landsat 5

Keywords

  • Landsat 7

Keywords

  • Landsat 8

Keywords

  • Earth Observations from Space

Keywords

  • rs0

Keywords

  • Pixel Quality

Keywords

  • Data

Australian and New Zealand Standard Research Classification: Fields of Research

  • Earth Sciences

Keywords

  • Published_External

Resource constraints

Title

Creative Commons Attribution 4.0 International Licence

Alternate title

CC-BY

Edition

4.0

Website

http://creativecommons.org/licenses/

Access constraints
License
Use constraints
License

Resource constraints

Title

Australian Government Security ClassificationSystem

Edition date
2018-11-01T00:00:00
Website

https://www.protectivesecurity.gov.au/Pages/default.aspx

Classification
Unclassified
Language
English
Character encoding
UTF8

Distribution Information

Distributor contact
Role Organisation / Individual Name Details
Distributor

Commonwealth of Australia (Geoscience Australia)

 Voice
OnLine resource

GA Landsat 8 OLI/TIRS Analysis Ready Data Collection 3

GA Landsat 8 OLI/TIRS Analysis Ready Data Collection 3

Distribution format

Resource lineage

Statement

As Landsat Imagery becomes more readily available, there has been a rapid increase in the amount of analyses undertaken by researchers around the globe. Most researchers use some form of quality masking schema in order to remove undesirable pixels from analysis, whether that be cloud, cloud shadow, observations over the ocean, or saturated pixels. In the past, researchers would reject partly cloud-affected scenes in favour of cloud-free scenes. However, Landsat time series analysis using all cloud-free pixels has become a valuable technique and has increased the demand for automation of cloud, cloud shadow and saturation detection. Emergency response applications such as flood mapping typically have to contend with individual cloud affected scenes and therefore rely on effective cloud and cloud shadow removal techniques.

The PQ25 product combines established algorithms that detect clouds including the Automated Cloud Cover Assessment (ACCA) (Irish et al. 2006) and Function of mask (Fmask) (Zhu and Woodcock 2012) . ACCA is already widely used within the remote sensing community; it is fast and relatively accurate. Fmask on the other hand is newer, but is rapidly becoming more established, and can provide a more accurate cloud mask than ACCA in certain cloud environments.

The sensor saturation flagging protocols developed for the Web Enabled Landsat Data (WELD) product as described in Roy et al. (2011) are used to flag sensor saturation.

The PQ25 product has similarities to the QAB layer packaged with OLI data, however it uses additional algorithms to detect cloud and cloud shadow, and is available for Landsats 5, 7 and 8.

Hierarchy level
Dataset
Description

Please refer to the lineage section.

Reference System Information

Reference system identifier
EPSG/GDA94 / Australian Albers (EPSG: 3577)

Title

European Petroleum Survey Group (EPSG) Geodetic Parameter Registry

Date (Publication)
2008-11-12T00:00:00
Cited responsible party
Role Organisation / Individual Name Details

European Petroleum Survey Group

 http://www.epsg-registry.org/

Metadata constraints

Title

Australian Government Security ClassificationSystem

Edition date
2018-11-01T00:00:00
Website

https://www.protectivesecurity.gov.au/Pages/default.aspx

Classification
Unclassified

Metadata

Metadata identifier
urn:uuid/7ba82c39-e9aa-418c-9a6b-9d6dd543b665

Title

GeoNetwork UUID

Language
English
Character encoding
UTF8
Contact
Role Organisation / Individual Name Details
Point of contact

Geoscience Australia

 Voice
Title

GA Earth Observation - Data

Edition date
2016-01-01T00:00:00
Citation identifier
3a2cd509-0e82-4381-98c7-522756da533b

Type of resource

Resource scope
Dataset

Alternative metadata reference

Title

Geoscience Australia - short identifier for metadata record with

uuid

Citation identifier
eCatId/102290

Metadata linkage

https://ecat.ga.gov.au/geonetwork/srv/eng/catalog.search#/metadata/7ba82c39-e9aa-418c-9a6b-9d6dd543b665

Date info (Revision)
2018-06-14T05:16:53
Date info (Creation)
2016-09-13T10:12:13

Metadata standard

Title

AU/NZS ISO 19115-1:2014

Metadata standard

Title

ISO 19115-1:2014

Metadata standard

Title

ISO 19115-3

Title

Geoscience Australia Community Metadata Profile of ISO 19115-1:2014

Edition

Version 2.0, September 2018

Citation identifier
https://pid.geoscience.gov.au/dataset/ga/122551

 
 

Spatial extent

N
S
E
W


Keywords

Australian and New Zealand Standard Research Classification: Fields of Research
Earth Sciences

Provided by

Access to the portal

Associated resources

Not available