1 / 20

Beyond Spectral and Spatial data: Exploring other domains of information: 1

Beyond Spectral and Spatial data: Exploring other domains of information: 1. GEOG3010 Remote Sensing and Image Processing Lewis RSU. Domains of Information. spectral angular multi-temporal distance-resolved spatial. Domains of Information.

robertmwheeler
Télécharger la présentation

Beyond Spectral and Spatial data: Exploring other domains of information: 1

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Beyond Spectral and Spatial data:Exploring other domains of information: 1 GEOG3010 Remote Sensing and Image Processing Lewis RSU

  2. Domains of Information • spectral • angular • multi-temporal • distance-resolved • spatial

  3. Domains of Information • consider physical basis for information

  4. Spectral - Physical Basis • Optical • reflectance varies with wavelength • spectral reflectance of different cover types / properties vary

  5. Spectral reflectance • Related to: • how much (projected, illuminated) material seen

  6. Spectral reflectance • Related to: • reflectance / absorptance characteristics of materials

  7. Plus multiple scattering where absorptance low

  8. Leaves • Absorbtance by leaf pigments, water etc • Acting in different parts of the spectrum

  9. Leaves Factors affecting reflectance/transmittance of plant elements • pigment type/concentration • e.g. Chlorophyll a,b - absorb visible radiation • surface features: • hairs, spines, veins, cuticular wax - scattering (e.g. specular) • cell morphology and content • NIR - high refl. due to scattering at refractive index discontinuities (nair = 0; ncell=1.47) • MIR - water absorption features

  10. So …attempt to take RS measurement and relate to • cover type • different spectral properties • amount of material (eg vegetation) • eg leaf • high NIR, low visible (basis of VIs)

  11. Interpretation complicated by: • variations in Sun/view angle

  12. -60 -30 0 30 60 e.g. 5m mean tree spacing SZA = 0 degrees

  13. -60 -30 0 30 60

  14. Interpretation complicated by: projection of objects • orientation (leaf angle distribution)

  15. Interpretation complicated by: projection of objects

  16. Interpretation complicated So relationship between eg VI and canopy variables (LAI) depends on cover type (different canopy structure)

  17. Microwave • Similar ‘spectral’ concepts (frequency c = f ) • again generally related to amount of material • but very much driven by: • water content • size of objects (relative to wavelength) • orientation • effect dept. on polarisation

  18. Summary • Spectral • cover type variation • spectral properties (of leaves, soil etc.) • projected towards viewer, illuminated • depends on amount of material • Vis - e.g. NDVI - quantify amount • relationships depend on cover type

More Related