Monitoring tropical forest cover - Activities of ONFI in remote sensing, Anne-Cécile Capel

1. ©ONF International©ONF International
ONF International
1
Monitoring tropical forest cover
Activities of ONFI in remote sensing
OTB Hackfest 2015
Anne-Cécile Capel
Forest GIS & Remote Sensing Expert
ac.capel@onfinternational.com

2. ©ONF International©ONF International
• REDD+ projects / Carbon sink projects
• Historical scenario for deforestation
• Regular forest monitoring every 5 years
• Impact assessment of logging activities on certified concessions with very
high resolution data from satellite or drone
• Plantations monitoring (agroforestry / CDM projects from Kyoto protocol)
• Quality assessment of land cover maps (more than 700 000 km2 in 2 years)
• Capacity building in remote sensing to support countries in the monitoring of
their forests (Burkina Faso, Cameroun, Maroc, Suriname, Guyana, AMAPA
state, Colombia…)
International firm of foresters and remote sensing experts specialized in
forest management in tropical regions
2
ONFI activities

3. ©ONF International©ONF International
3
Data and Software
Priority given to free data and open source software
• OTB via processing toolbox in QGIS interface
• Sentinel1-Toolbox and PolSARPro to process SAR data
• Pansharpening
• SVM classifier – Land Cover maps from optical or radar data / clouds detection
• Anysotropic filtering – to reduce noise from VHR data
• Meanshift segmentation
• Texture analysis (Haralic) – to process VHR data
• Band Math

4. ©ONF International©ONF International
Support countries to use satellite images to monitor their forests
4
Capacity building
• Training sessions on QGIS /OTB
• OTB Installation via QGIS – simplification via portable QGIS in USB key
including all libraries and parameters – ready to play
• OTB Tools are still complicated to use for new users
• Menu simplification for SVM classification (reduce number of fields, file
extensions suggested)
• Menus personalization in Processing toolbox (as processing chain)
• Creating models when it’s possible (doesn’t work for SVM)
• Online video tutorials on Youtube:
https://www.youtube.com/channel/UCQGbTotYoV6SBN-
Qr0AN69Q/videos

5. ©ONF International©ONF International
5
To improve… and missing tools
Functionalities for OTB GUI / CLI
To improve:
• In OTB 4.2 Linux the projection information on big files (to confirm…) is lost after
a classification
• In OTB 4.2 the conditional syntax ? : is not recognized on Windows
• Models on QGIS Processing toolbox doesn’t work due to missing file extension
• Compilation by default (in OSGEO4W and otb-bin package)
of speckle filter and SVM growing (Win + linux)
To add:
• SVM : Stratified random points for training and cross validation
• SVM : Get access to intermediate product containing distance of each class to
hyperplan – similar to probability map by class

6. ©ONF International©ONF International
6
To improve… and missing tools
Functionalities for OTB GUI / CLI
To add:
• Adding shape factor (flusser moment) in segmented vector file to start with
OBIA (ex: otbgui_LSMSVectorization)
• OBIA processing chain (not only on Monteverdi 1) without image size constraint
• Active learning: be able to reallocate misclassified pixels – easy way to improve
ROI
Methodology improvement and axes of research for ONFI
• Improve change detection method
• How improve the detection of tracks in tropical forest?
• How improve the forest segmentation with VHR images (from drone or satellite)
• One single interface to work with vectors / optical data / SAR data