1) The document describes several use cases for processing and analyzing satellite images using the Orfeo Toolbox framework and Monteverdi application.
2) The use cases include opening an image and exploring the viewer tools, creating an ROI, thresholding, mean-shift segmentation, feature extraction, image concatenation, supervised SVM classification, unsupervised k-means clustering, and orthorectifying images with and without a DEM.
3) Advanced functions covered include superimposing a XS image over a higher resolution THR image using their geometric models.
1. Use cases with the Orfeo Toolbox
framework Monteverdi
orfeo-toolbox.org
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2. Use case 1 : open an image, and discover the viewer
Menu File > Open
.//theme2/IM2/Im2_C_02112006_169_388/372596101/SPVIEW01
/IMAGERY.TIF
Menu Visualization > Viewer
(Alternative – right click on the module in the pipeline)
Discover the viewer functionalities
orfeo-toolbox.org
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7. Use case 2 : create a pipeline, save an image
Menu File > Open
./theme2/IM2/Im2_C_02112006_169_388/372596101/SPVIEW01/
IMAGERY.TIF
Menu Visualization > Viewer (lock the pipeline !)
File > Extract ROI from dataset
Positions (x,y) = [1600,1000], sizeX=2000 (w), sizeY=1500 (h)
File > Save dataset
File > Save dataset (advanced)
Save only Channel 1 in Float type
Seel also :
Right click on pipeline module ExtractROI > Show module
Cache dataset
orfeo-toolbox.org
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12. Use case 4 : segmentation with mean-shift
Menu File > Open
./data_tp/theme2/IM2/extraitIm2_C/Im2_c_extrait.tif
Menu Filtering > Mean-shift clustering
Change radius : 5
Spectral radius : 15
Min region size : 15
Clusters : ON
Change values and Click on Run button
Click on Close button after selecting right set of parameters
See also :
➢ Image filtered / Image clustered
➢ See OTB-Software-Guide_V3.0.pdf p 174 orfeo-toolbox.org
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14. Use case 5 : Feature extraction (1/2)
Menu File > Open
./theme2/IM2/extraitIm2_C/Im2_c_extrait.tif
Menu Filtering > Feature extraction
Test the following features (See OTB-Software-Guide_V3.0.pdf for
technical details on algorithms)
➢ Edge detection : Touzi
➢ Spectral angle : choose one vegetation pixel
➢ Variance
➢ Mean
➢ Rec. gradient
➢ Morphology > Morphology opening
➢ Edge density > Sobel
➢ Original data (=> no need to concatenate channels after filtering)
orfeo-toolbox.org
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15. Use case 5 : Feature extraction (2/2)
Menu Filtering > Feature extraction
Test the following features (See OTB-Software-Guide_V3.0.pdf for
technical details on algorithms) :
➢ Radiometric indexes
Vegetation
• NDVI, RVI, PVI, etc
Soil
• BI2
Built up
• ISU
Further work :
➢ Rename output image channels
➢ Save your result
➢ Build Mean, variance image on a Touzi image orfeo-toolbox.org
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18. Monteverdi – Feather extraction
Solution : mean, variance over Touzi image
Reader
Feature Extraction (Reader0) > Touzi
Feature Extraction (FeatureExtraction1) > Mean, Variance
Save your result
orfeo-toolbox.org
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19. Use case 6 : concatenate your results
Menu File > Open
./theme1/IM2/Extraits/Ext_IM2_04102008_10mC.tif
Menu Filtering > Feature extraction > NDVI
Menu File > Concatenate Image
Add Reader0 → Channel 1
Add Reader0 → Channel 2
Add FeatureExtraction1 → OutputImage
View the result
orfeo-toolbox.org
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21. Use case 7 : supervised classification with SVM
Menu File > Open
./theme2/IM2/extraitIm2_C/Im2_c_extrait.tif
Menu Learning > SVM Classification
Create several classes (4-5)
➢ Edit names
➢ Change colors
➢ Select polygons
Learn
Validate
Display
Further work :
Same case with concatenated NDVI channel orfeo-toolbox.org
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25. Use case 8 : unsupervised clustering with k-means
Menu File > Open
./theme2/IM2/extraitIm2_C/Im2_c_extrait.tif
Menu Learning > k-means clustering (doc
OTBSoftwareGuide_V3.0.pdf p 448)
Training 15%
Number of classes : 5
Iteration number : 1
Convergence : 0.0001
Further work :
Compare with SVM supervised classification
orfeo-toolbox.org
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27. Use case 9 : orthorectify an image (Spot 5 level 1A)
without DEM
Menu File > Open
./reunion_S5/thr1a/imagery.tif
Menu Geometry > Orthorectification
Size X : 220, Size Y : 200
(try larger size with powerful computers)
Spacing X : 10, Spacing Y : -10 (m)
Longitude : -55.4, Latitude : -21.0
UTM / Linear
(=> Module created in pipeline)
Visualization > Viewer (Orthorectifcation0) > Click on
Streamed / Cache (This launches the orthorectification).
“Cached” : click on OK to view the image
orfeo-toolbox.org
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30. Use case 10 : orthorectify an image (Spot 5 level 1A)
with DEM
Menu File > Open
./reunion_S5/thr1a/imagery.tif
Menu Geometry > Orthorectification
Size X : 220, Size Y : 200
(try larger size with powerful computers)
Spacing X : 10, Spacing Y : -10 (m)
Longitude : -55.4, Latitude : -21.0
UTM / Linear
DEM : enter the directory where .hgt files are
Visualization > Viewer (Orthorectifcation0) > Click on
Streamed / Cache (This launches the orthorectification).
“Cached” : click on OK to view the image
orfeo-toolbox.org
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31. Use case 11 : Superimpose XS image over THR one (1/2)
Menu Geometry > Superimpose two images
Combination of geometric models of the two images (note : works with
images with geometric model)
➢ Image to be superimposed : use of the direct geometric model to
build Longitude/Latitude projection
➢ Combination with the inverse model of the reference image.
➢ Reprojection
orfeo-toolbox.org
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32. Use case 11 : Superimpose XS image over THR one (2/2)
Menu File > Open
./reunion_S5/thr1a/imagery.tif
Menu Geometry > Orthorectification
Size X : 220, Size Y : 200
Spacing X : 10, Spacing Y : -10 (m)
Longitude : -55.4, Latitude : -21.0
UTM / Linear
Menu Geometry > Superimpose two images
Image to reproject : J1A / XS image
Reference Image : ortho of THR1A / Panchromatic image
Choose the same DEM model
Visualization > Viewer (Reprojected Image) > Stream /
Caching... / Cached orfeo-toolbox.org
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