Remote Sensing with Multiple Types of Photographs

Shuntaro Otsubo, Susumu Ogawa, Haruhiro Hidaka, Tran Thanh Dan,

Yoichi Imamura

Nagasaki University

IntroductionRecently, UAV (Unmanned Aerial Vehicle) technology are developed rapidly. UAV may work at lower cost than satellite or aerial photos. The expansion of research for UAV is expected. However, the number of bands for UAV is less than satellite images. In this study, UAV, a digital camera, aerial photos, and satellite data were used in multiple types.

Phantom 4

Objectives• To get RGB, near infrared, and short infrared images with high resolution in multiple types by UAV and a digital camera.

• To obtain NDVI and NDWI images with UAV and a digital camera. NDWI is a normalized difference water index.

• To monitor vegetation covers and to make a land-use map with UAV and a digital camera.

Photographing methods with UAV

• IR72 filter is a band pass filter more than 720 nm. Near infrared photos are taken with UAV and a digital camera with an IR 72 filter. Additionally, IR90 filter is a band pass filter more than 900 nm. Short infrared photos are taken with UAV and a digital camera with an IR 90 filter.

IR72 filter

Methods: Paddy field map•Band 3 distributions were calculated in the survey field with PhotoScan. Band 3 distribution made paddy field maps because vegetation absorbed Band 3, red.

Study area

Onigi paddy fields

NDVI at Onigi village (July 30 2016)

RGB image with UAV

NIR image with UAV

NDVI image in Hasami with UAV

Orthogonal images with UAV (left) and aerial photos (right) at Onigi village

Resolution: 6 cm

Fine resolution DEM at Onigi

Resolution: ~10 cm

NDWI at Onigi village (July 30 2016)

Rice paddy fields

Detecting a land use map at Onigi village

Tea plantatio

ns

Rice paddy fields

Abandoned Fields

CONCLUSIONS•RGB, near infrared, and short infrared images were obtained by a digital camera with band pass filters, while RGB and near infrared were inquired by UAV with 6 cm resolution.

•NDVI images were obtained by a digital camera and UAV with IR72, while NDWI images were estimated by a digital camera with IR72 and IR90, which estimates water contents and permeability in soils.

•Vegetation cover was monitored in any time and also land use map was obtained with fine-resolution DEM.

Thank you for your attention