Cloud-shadow suppression technique for enhancement of Airborne Thematic Mapper imagery

Journal Article · Sun Aug 01 04:00:00 EDT 1993 · Photogrammetric Engineering and Remote Sensing; (United States)

OSTI ID:5548052

Guo, L J; Moore, J M ^[1]

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1. Imperial College of Science, Technology, and Medicine, London (United Kingdom)

Airborne Thematic Mapper (ATM) data are often degraded by the shadows from clouds above the aircraft during the flight. The spectral information in cloud-shadowed areas is reduced but not totally lost because the reflected energy of diffuse illumination (sky light) reaches the sensors from the shadowed ground despite obstruction of direct solar radiation. The thermal band image is almost unaffected by the temporary change of radiation caused by clouds. An enhancement technique for cloud-shadow suppression has been developed based on differencing, RGB-HSI-RGB transformation, and thermal band modulation. The method suppresses cloud shadows with topographic shading retained; spectral information is retrieved and enhanced. The result is a nearly normal color composite with full topographic expression but without cloud shadows. Such a color composite is easy to interpret for geological structures and lithologies. 6 refs.

• OSTI ID: 5548052
• Journal Information: Photogrammetric Engineering and Remote Sensing; (United States), Journal Name: Photogrammetric Engineering and Remote Sensing; (United States) Vol. 59:8; ISSN PERSDV; ISSN 0099-1112
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
540210 -- Environment
Terrestrial-- Basic Studies-- (1990-)
CLOUD COVER
IMAGE PROCESSING
MULTISPECTRAL PHOTOGRAPHY
PHOTOGRAPHY
PROCESSING
REMOTE SENSING