Request for Changes-101: Optimization of SampleExtraction
Contents
[Request for Changes - 101] Optimization of SampleExtraction
Status
- Author: Guillaume Pasero
- Additional Contributors (if different than authors)
- Submitted on dd.mm.yyyy
- Proposed target release
- Adopted / Rejected (with vote results)
- Branch : optim_sample_extract
Summary
This RFC introduces optimization in the sample extraction process.
Rationale
The sample extraction step is often performed after having computed a set of features on the initial image. This feature extraction step can be demanding in computation time. If there are areas where no sample has been selected, then these areas can also be skipped when computing classification features.
Implementation details
Classes and files
M Modules/Learning/Sampling/include/otbImageSampleExtractorFilter.txx M Modules/Learning/Sampling/include/otbPersistentSamplingFilterBase.txx
The main idea of this optimization is to skip tile where there is no sample, and also to compute the useful extent of non-empty tiles
The changes made to the base class otb::PersistentSamplingFilterBase should allow to detect empty tiles (tiles without selected samples) during the GenerateInputRequestedRegion() step. This way, when an empty tile is found, the requested region for the feature image is set empty.
