Zonalstatistics

Summary

Add a new application for zonal statistics.

Rationale

There is currently no such application in the Orfeo ToolBox. This application enables to compute statistics (min, max, mean, standard deviation) of objects in a vector image.

Implementation Details

Input objects can be described from a vector data, or from a label image:

• mode vector: the VectorData is rasterized at the same origin/spacing/size as the input image. Polygons are numbered starting from 0. The statistics are computed using a StreamingStatisticsMapFromLabelImageFilter.
• mode label image: the statistics are directly computed using a StreamingStatisticsMapFromLabelImageFilter, from the input image and the label image.

The application enables to produce output stats in multiple forms:

• as XML (Using a XMLFileWriter as the ComputeImagesStatistics application do),
• VectorData (stats are written in features of each polygons),
• or Raster (stats are stored in bands of the output image)

Classes and files

• A new application in AppClassification: ZonalStatistics (otbZonalStatistics.cxx)
• 5 tests were added in AppClassification/test

Applications

New: ZonalStatistics application (otbZonalStatistics.cxx)

Tests

• Input vector / Output vector
• Input raster / Output XML (without nodata-value for the label image)
• Input raster / Output XML (with nodata-value for the label image)
• Input vector / Output raster
• Input raster / Output raster

I've pushed a new branch in otb-data called "zonalstatistics" which contains new files in baseline and input:

• Baseline/apTvClVectorData_QB1_ter_with_stats.sqlite
• Input/Classification/VectorData_QB1_ter.tif
• Baseline/apTvClVectorData_QB1_ter_stats.xml
• Baseline/apTvClVectorData_QB1_ter_stats_nodata.xml

Additional notes

Please feel free to discuss this feature.

Copyright

The copyright owner is IRSTEA and has signed the ORFEO ToolBox Contributor License Agreement.

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***Check before merging:*** - All discussions are resolved - At least 2 votes from core developers, no vote. - The feature branch is (reasonably) up-to-date with the base branch - Dashboard is green - Copyright owner has signed the ORFEO ToolBox Contributor License Agreement