Remote sensing. Introduction, application & examples of optical satellite imagery. Ge /Week-4

Transcription

1 Remote sensing Introduction, application & examples of optical satellite imagery Ge /Week-4

2 Mapping What can we use it for? The remote sensing data can be used in Geologic mapping, vegetations etc. Monitor Tectonic deformation, deforestation.. etc. Quick response Hazard estimations etc. Make DEM (Digital Elevation Model) and more

3 Common types of remote sensing s s data source Active system Radar Lidar Sonar Passive system Aerial photo Satellite image Google Earth history image

4 Common types of remote sensing s s data source Active system Radar Lidar Sonar Passive system Aerial photo Satellite image

5 What do we need to know.. Image Acquisition Image Processing Image Interpretation

6 What do we need to know.. Image Acquisition Image Processing Image Interpretation Across-Track Scanner Push-broom Scanner Framing Camera

7 What do we need to know.. Image Acquisition Image Processing Image Interpretation Across-Track Scanner Push-broom Scanner Framing Camera

8 What do we need to know.. Image Acquisition Image Processing Image Interpretation ENVI ERDAS IMAGINE Matlab, IDL PCI Geomatics.. etc.

9 What do we need to know.. Image Acquisition Image Processing Image Interpretation Your brain Tools

10 Satellite (sensor) you should know Landsat (Landsat-1 1 to Landsat-7) ASTER (Terra) MODIS (Terra / Aqua) SPOT (SPOT1 to SPOT5) IKONOS Quickbird etc. You can find more information from

11 Satellite (sensor) you should know Landsat (15 120m) ASTER (15 90m) MODIS ( m) SPOT (2.5 20m) IKONOS ( m) Quickbird ( m) You can find more information from

12 Swath (KM) Res(min) Res(MAX) Landsat Landsat ASTER MODIS ALOS(PRISM) SPOT SPOT SPOT FORMOSAT QuickBird WorldView WorldView Geoeye IKONOS OrbView AVHRR Corona KH KH

13 Swath (KM) Geoeye-1 WorldView 0 KH-7 KH-9 IKONOS QuickBird ALOS(PRISM) Price FORMOSAT-2 SPOT5 5 Corona Resolution (m) SPOT1-3 SPOT4 ASTER Landsat 7 20 MODIS AVHRR 25

14 Please keep in mind.. Satellite image Photo Image color real color (CORONA) (Quick Brid, from Google Map)

15 Please keep in mind.. Satellite image Photo Image color real color Landsat L0R

16 Please keep in mind.. Satellite image Photo Image color real color Aster data level Level Product Description 1A 1B Radiance at sensor Registered radiance at sensor Image data plus radiometric and geometric coefficients. Data are separated by telescope 1A data with radiometric and geometric coefficients applied 2 AST09 Surface radiance Radiance corrected for atmospheric effects 3 AST14 Digital elevation model AST14OTH AST14DMO DEM produced by stereo correlation of nadir and aft Band 3 data 15 orthorectified L1B radiance images, in GeoTiff 15 orthorectified L1B images + DEM

17 Please keep in mind.. Satellite image Photo Image color real color

18 Please keep in mind.. Satellite image Photo Image color real color Landsat 7 (ETM+ sensor) Wavelength (micrometers) Resolution (m) Band Blue Band Green Band Red Band Near IR Band Mid IR Band Thermal Band Mid IR Pan Band VIN Near IR

19 True Color R/G/B = R/G/B Natural looking Provides the best water penetration

20 False Color R/G/B = NIR/R/G Most common false color combination. It gives results similar to traditional color infrared aerial photo.

21 Band combinations: Why we want to use different band combinations in the satellite image? (From: ASTER Mineral Index Processing Manual) Different types of surface/material are sensitive in different wavelength, false color image can let our research target stands out.

22 MODIS (Moderate Resolution Imaging Spectroradiometer) MODIS Wavelength (nm) Res (m) Band R Band N IR Band B Band G Band N IR Band M IR Band M IR

23 R/G/B = 1/4/3 (R/G/B)

24 R/G/B = 7/2/1 (M IR/N IR/R)

25 R/G/B = 1/4/3 (R/G/B)

26 R/G/B = 7/2/1 (M IR/N IR/R)

27 Other than single band combinations: There are other way to display (analysis) our satellite image.. R-G-B = R-G-B = Band Ratio R-G-B = 6-3/2-4/5 PCA analysis R-G-B = PC

28 False-colour images sometimes is a kind of standard imagery. False-colour doesn't mean that it must looks weird Landsat 7 (ETM+ sensor) Wavelength (micrometers) Band B Band G Band R Band N IR Band M IR Band Th Band M IR Pan Band ASTER (sensor) Wavelength (micrometers) B1 VNIR_Band B2 VNIR_Band B3 VNIR_Band3N/B B5 SWIR_Band B6 SWIR_Band B7 SWIR_Band B8 SWIR_Band B9 SWIR_Band B10 SWIR_Band B11 TIR_Band B12 TIR_Band B13 TIR_Band B14 TIR_Band B15 TIR_Band

29 False Color RGB = 321 R = N-IR G = Red B = Green

30 False Color RGB = 231 R = Red G = N-IR B = Green

31 How about satellite that provides the high-res image? They usually provides good imagery, but not as many bands as those satellite Sensor spectrum pixel size spectral bands SPOT 5 SPOT 4 SPOT 1 SPOT 2 SPOT 3 Panchromatic B1 : green B2 : red B3 : near infrared B4 : mid infrared (MIR) Monospectral B1 : green B2 : red B3 : near infrared B4 : mid infrared (MIR) Panchromatic B1 : green B2 : red B3 : near infrared 2.5 or 5 m 10 m 10 m 10 m 20 m 10 m 20 m 20 m 20 m 20 m 10 m 20 m 20 m 20 m µm µm µm µm µm µm µm µm µm µm µm µm µm µm Sensor QuickBird IKONOS spectrum Panchromatic B1 : Blue B2 : Green B3 : Red B4 : near infrared (NIR) Panchromatic B1 : Blue B2 : Green B3 : Red B4 : near infrared (NIR) pixel size 0.6 m 2.4 m 2.4 m 2.4 m 2.4 m 0.8 m 3.2 m 3.2 m 3.2 m 3.2 m spectral bands µm µm µm µm µm µm µm µm µm µm PRISM Panchromatic 2.5 m µm

32 Enhanced color image FORMOSAT 2 (Panchromatic, 2m)

33 Enhanced color image FORMOSAT 2 (Multispectral, 8m)

34 Enhanced color image FORMOSAT 2 (Pansharp image, 2m)

35 Other satellite image products from modern satellites

36 Try yourself Open LANDSAT and ASTER image in ENVI Make a false color image Band combinations / Band Ratios / PCA Output your image to Arc-Map

37 Work with ENVI

38 Open LANDSAT 1. Upzip all the.gz files 2. Find and open.met file 3. If your don t have.met file, open all.tiff files 4. Select the band you want to display, and load.

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41 RGB = 321

42 RGB = 321 RGB = 753

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44 Output the Geotiff

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46 Band transformations Band ratio PC transformation (PCA) MNF transformation

47 Make a pan-sharpening image LANDSAT-7 Band 8 (15m) LANDSAT-7 Band 3 (30m)

48 Make a pan-sharpening image LANDSAT-7 15m Color (Pan) LANDSAT-7 30m RGB (7,3,1)

49 Make a pan-sharpening image B/W High-Res Color Low-Res Intensity Color info Colored image

50 Make a pan-sharpening image B/W High-Res Color Low-Res Intensity Color info Colored image

51 Make a pan-sharpening image B/W High-Res Color Low-Res Intensity Color info Colored image

52 Make a pan-sharpening image