Texture and Change detection

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• Texture and Change detection
• Dave Nys
• Prof Pol Coppin, Dr Stefan Fleck, Dr Kris
  Nackaerts
• K.U.Leuven
• Laboratory for Forest, Nature and Landscape
  Research
• Vital De Costerstraat 102 B-3000 Leuven
• Tel. [phone] Fax. [phone]
• email Dave.Nys_at_agr.kuleuven.ac.be

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Pijnven

• Pine forest
• Corsican Pine
• Scots Pine
• Situated in northern part of Belgium
• Flemish government

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Pijnven 2

• Vitality Problem
• Change detection
• CHRIS Hyperspectral
• Multi-temporal
• Variety of homogeneous stands
• Age
• Plantation
• Thinning
• Texture analysis
• CHRIS Multiple View Angle

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Vitality

• Corsican pine
• Defoliation
• Discolouring of needles
• But normal to high production of wood
• Main objective cross-correlate spectral
  characteristics to biophysical properties of the
  stands
• Wavelength of Red edge chlorophyll ?
• Area of Red edge peak LAI ?

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Vitality 2

• Similar task on orchard trees
• Problem
• Damage at individual trees
• Chris image resolution

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Texture

• Image texture
• not only surface reflectance
• also from height variations
• 3D texture depends on illumination and viewing
  angle
• Bi-directional Texture Function (BTF) BRDF
• Forest
• Discontinued canopy
• Structural variability
• ?different stands will have different BTF

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Texture 2

• Objective relationship between
• 3D image texture parameters
• Structural parameters of forest stand
• biophysical forest parameters (e.g. LAI)
• Up to now Modelling
• Canopy-level

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In situ data collection

• Texture On different stands
• Biophysical
• LAI
• LICOR2000
• TRAC
• Hemispherical photography
• Structural
• Height , dbh
• Crown dimensions
• Stem density
• Vitality On the infected stands
• Chlorophyll
• Fluorescence

http//www.ccrs.nrcan.gc.ca/ccrs/rd/apps/landcov/b
eps/trac_e.html
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CHRIS

• Mode 4
• 19 bands _at_ ?20m
• Vitality
• Hyperspectral images at different times in the
  year
• April, June, July, August
• Texture
• Multiple view angles
• 5 angles
• 4 times a serie of 5 mva images of Pijnven forest