第五章 遥感图像的校正与定标 1
1 第五章 遥感图像的校正与定标 UESTC-RSIP
图像几何形变 INCLINATION OF LANDSAT ORBIT TO C-RSIP Orbit 16,day 2 Orbit 2.day I MAINTAIN SYNCHRONOUS ORBIT Orbit 15,dey 2 LANDSAT AT12为NO0 Orbit 1.day I LOCAL TIME EQUATORIAL AN 1851 LANDSAT AT 042 AM LOCAL TIME 2875 km at the Equator 159hm 2
2 图像几何形变 UESTC-RSIP
Equatorial 98.29 plane and direction of Earth rotation: west to cast Landsats 4.5.7 ocal time Pixels in a Landsat Thematic Pixels in a Landsat Thematic Mapper dataset prior to correcting Mapper dataset corrected for Earth rotation effects for Earth rotation effects Landsat Earth rotates satellite TC-RSIP west to east line of flight ↓ 23456 Entire scan consisting of 16 lines offset to correct for Earth rotation effects Usually padded with null values (e.g.BVij=0) 3 ■■■■■■■■■■■■■ contimed continued
3 UESTC-RSIP
Corrected image scene orientation 'map' Uncorrected data 'path USGS 1 millionth Landsat scene downloaded G时C我SA Ladh减5 = 4
4 Corrected image scene orientation ‘map’ Uncorrected data ‘path’ UESTC-RSIP
Scanning System-induced Variation in Ground Resolution Cell Size The ground resolution cell size along a single across-track scan is a function of a) the distance from the aircraft to the observation where H is the altitude of the aircraft above ground level (AGL)at nadir and H sec f off-nadir; Total field b) the instantaneous-field-of-view of the of view of sensor,b,measured in radians;and one scan line c) the scan angle off-nadir,f.Pixels off- =Hsec nadir have semi-major and semi-minor B axes (diameters)that define the Instantaneous 4 field of view resolution cell size.The total field of Scan angle view of one scan line is q. off-nadir (H sec B (H sec)B D=BxH at nadir Lime of flight 5
5 Scanning System-induced Variation in Ground Resolution Cell Size The ground resolution cell size along a single across-track scan is a function of a) the distance from the aircraft to the observation where H is the altitude of the aircraft above ground level (AGL) at nadir and H sec f off-nadir; b) the instantaneous-field-of-view of the sensor, b, measured in radians; and c) the scan angle off-nadir, f. Pixels offnadir have semi-major and semi-minor axes (diameters) that define the resolution cell size. The total field of UESTC-RSIP view of one scan line is q