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Image Data Purchase and Pre-processing. Litia Gaunavou SPC-SOPAC. Pre-Processing. Image Stitching Ortho-Correction Haze removal Atmospheric correction Pan-sharpening. Image Stitching. Stitched Image. Ortho Correction. Ortho correction requires a DTM
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Image Data Purchase and Pre-processing LitiaGaunavou SPC-SOPAC
Pre-Processing • Image Stitching • Ortho-Correction • Haze removal • Atmospheric correction • Pan-sharpening
Image Stitching Stitched Image
Ortho Correction • Ortho correction requires a DTM • the DTM should have similar scale as image data
New Satellites: GeoEye-1WorldView-1, WorldView-2 • High geo-accuracy ~ 5m • Star tracker • Advanced GPS position • Ortho Correction required to activate high geo-accuracy
Haze Removal Raw LandSat 4 TM (Fiji – 1991) Haze Corrected LandSat 4 TM
Atmospheric Correction • - View Angle • - DEM • Sensor type • Calibration data • Sun angle
Corrected Image Raw ALOS Image (Fiji 2007) ALOS Image + atmospheric correction
IHS Transformation • Intensity • Hue • Saturation
IHS Transformation and Re-Transformation in ERDAS Imagine Red Intensity Red Green Hue Green Blue Saturation Blue
Pan-Sharpening IHS Resolution Merge Panchromatic Image Data Red Red Intensity Resolution increase Green Green Hue Hue Blue Saturation Saturation Blue Normal Bands Pan-sharpened IMG
Casuarina Bands: 1, 2, 3, pan-sharpened natural colour combination
Casuarina Bands: 2, 3, 4 pan-sharpened false colour infrared
Casuarina Vegetation Index Bands: 4 – 3 / 4 + 3
Radiometric Resolution Near IR 2 Red Coastal Green Yellow Near IR 1 Blue Red Edge
Current WV-2 Bundle Data Backdrop Products: • Pan-sharpened natural colour • Pan-sharpened false colour IR • Pan-sharpened false colour RE • Vegetation index red / near IR • Vegetation index red / RE