Remote Sensing - unina.it · Microsoft PowerPoint - Presentazione1 Author: HP_Proprietario Created...
27
Remote Sensing Prof. Guido D’Urso, Phd University of Naples Federico II
Transcript of Remote Sensing - unina.it · Microsoft PowerPoint - Presentazione1 Author: HP_Proprietario Created...
Remote Sensing
Prof. Guido D’Urso, Phd
University of Naples Federico II
Earth Observation
platforms
Documento Acrobat
Sun-synchronous polar orbit
Sun-synchronous polar orbit
Electromagnetic radiation
Visible spectrum is only 0.3 nm wide
Sensor types
Passive optical systems
• multispectral scanners
• imaging sensors
Whiskbroom
(Landsat)
Pushbroom
(SPOT)
Passive optical systems
• multispectral ?
Surface reflectance
Hyperspectral
Multispectral
Water bodies - reflectance
Snow & Clouds
Jensen, 2000
What is a digital image ?
72808492979485787581
72707478859397888179
71616770768290979387
727479777579798910396
4459778785848897110105
563951839195101100104104
7558435684106106938693
78797541406587867988
78828672453244698280
85858684775938457779
87918881858464415370Pixel
Cosa vediamo noi…Cosa vede il computer…
Digital Number (DN)
I Digital numbers (DNs) 0 -255; 0 - 511; 0 - 1023, etc.Binary ranges 28=256; 29=512; 210=1024.
72808492979485787581
72707478859397888179
71616770768290979387
727479777579798910396
4459778785848897110105
563951839195101100104104
7558435684106106938693
78797541406587867988
78828672453244698280
85858684775938457779
87918881858464415370
A multispectral image
72808492979485787581
72707478859397888179
71616770768290979387
727479777579798910396
4459778785848897110105
563951839195101100104104
7558435684106106938693
78797541406587867988
78828672453244698280
85858684775938457779
87918881858464415370
72808492979485787581
72707478859397888179
71616770768290979387
727479777579798910396
4459778785848897110105
563951839195101100104104
7558435684106106938693
78797541406587867988
78828672453244698280
85858684775938457779
87918881858464415370
columns (x)rows (y)
bands (z)
72808492979485787581
72707478859397888179
71616770768290979387
727479777579798910396
4459778785848897110105
563951839195101100104104
7558435684106106938693
78797541406587867988
78828672453244698280
85858684775938457779
87918881858464415370
72808492979485787581
72707478859397888179
71616770768290979387
727479777579798910396
4459778785848897110105
563951839195101100104104
7558435684106106938693
78797541406587867988
78828672453244698280
85858684775938457779
87918881858464415370
72808492979485787581
72707478859397888179
71616770768290979387
727479777579798910396
4459778785848897110105
563951839195101100104104
7558435684106106938693
78797541406587867988
78828672453244698280
85858684775938457779
87918881858464415370
Synthetic color vision
R = 255
G = 0
B = 0
R = 255
G = 0
B = 0
R = 127
G = 0
B = 0
R = 0
G = 0
B = 0
R = 255
G = 127
B = 255
R = 255
G = 0
B = 255
R = 0
G = 0
B = 127
R = 0
G = 127
B = 0
R = 255
G = 255
B = 255
R = 0
G = 0
B = 255
R = 0
G = 255
B = 255
R = 0
G = 255
B = 0
R = 255
G = 255
B = 255
R = 255
G = 255
B = 255
R = 127
G = 255
B = 255
R = 0
G = 255
B = 0
Banda 3visibile
Banda 4infrarosso vicino
Banda 5infrarosso medio
vegetazione
suolo nudo
Il Molise visto dal satellite Landsat 5; immagini a falsi colori(Rosso= TM 3; Verde=TM4; Blu= TM5)
Foce del Biferno
Autostrada A14
Porto di Termoli
Spatial resolution
Landsat 7 ETM+ => 30 m
SPOT5 => 10 m
Quick Bird => 2,8 m
Temporal resolution: 16 gg.
Swath: 185 km
450 – 515 nm
525 – 605 nm
630 – 690 nm
750 – 900 nm
1.55 – 1.75 µm
2.09 – 2.35 µm
30 m
BandsSpatialresolution
10.4 – 12.5 µm60 m
520 – 900 nm15 m
Landsat ETM+
β
∆
A
Vegetation indexes
NDVI (Normalized Difference Vegetation Index)
rnir
rnirNDVIρρ
ρρ
+
−=
NDVI and vegetation growth
