GBDX

ENVI® Thematic Change

This task takes two classification images of the same scene taken at different times and identifies differences between them. The resulting classification image shows class transitions, for example, from class 1 to class 2. Thematic change detection can be used to analyze land use, land cover change, deforestation, urbanization, agricultural expansion, water variability, and more.

GBDX Registered Name: ENVI_ThematicChange

Provider: Harris Geospatial Solutions

Inputs

The following table lists all ENVI_ThematicChange inputs.
Mandatory (optional) settings are listed as Required = True (Required = False).

Name Required Default Valid Values Description
file_types False N/A string GBDX Option. Comma seperated list of permitted file type extensions. Use this to filter input files -- Value Type: STRING[*]
input_raster1 True N/A See ENVIRASTER input type Specify a classification raster representing the earliest time. -- Value Type: ENVIRASTER
input_raster1_format False N/A string Provide the format of the image, for example: landsat-8. -- Value Type: STRING
input_raster1_band_grouping False N/A string Provide the name of the band grouping to be used in the task, ie - panchromatic. -- Value Type: STRING
input_raster1_filename False N/A string Provide the explicit relative raster filename that ENVI will open. This overrides any file lookup in the task runner. -- Value Type: STRING
input_raster1_raw_output False False See ENVIRASTER input type Provide True to output an ENVI Binary instead of a tif. -- Value Type: STRING
merge_no_change False true string If the two input classification images have the same number of classes that use the same class name, set to true to group them into a class named no change if there was no difference detected during processing. Set to false if the output is a new classification image that includes all class transition information. -- Value Type: BOOLEAN -- Default Value: true
input_raster2 True N/A See ENVIRASTER input type Specify a classification raster representing the latest time. -- Value Type: ENVIRASTER
input_raster2_format False N/A string Provide the format of the image, for example: landsat-8. -- Value Type: STRING
input_raster2_band_grouping False N/A string Provide the name of the band grouping to be used in the task, ie - panchromatic. -- Value Type: STRING
input_raster2_filename False N/A string Provide the explicit relative raster filename that ENVI will open. This overrides any file lookup in the task runner. -- Value Type: STRING
input_raster2_raw_output False False See ENVIRASTER input type Provide True to output an ENVI Binary instead of a tif. -- Value Type: STRING
output_raster_uri_filename False N/A string Specify a string with the fully-qualified path and filename for OUTPUT_RASTER. -- Value Type: STRING

Outputs

The following table lists all ENVI_ThematicChange outputs.
Mandatory (optional) settings are listed as Required = True (Required = False).

Name Required Default Valid Values Description
task_meta_data False N/A directory GBDX Option. Output location for task meta data such as execution log and output JSON
output_raster_uri True N/A directory Output for OUTPUT_RASTER. -- Value Type: ENVIURI

Output structure

The output_raster_uri file will be written to the specified S3 Customer Account Location.

Background

For additional background information on this task please refer to the Harris Geospatial ENVI documentation and
ENVI® Thematic Change.

Contact

If you have any questions or issues with this task, please contact gbdx-support@digitalglobe.com.