Atmospheric correction of satellite data with haze removal including a haze/clear transition region

High spatial resolution satellite imagery such as LANDSAT TM and SPOT HRV may contain large regions covered with haze. By applying suitable thresholds, clear areas as well as haze and cloud regions can be separated and stored as binary images. Cloud areas are identified in the method presented here, but are not included in the haze correction, because ground information cannot be retrieved in optically thick regions. For each spectral band, the haze removal algorithm matches the histogram of the haze areas to the histogram of the clear part of the scene. Because of the binary nature of thresholding, this algorithm may cause sharply defined edges at the borders of haze regions. Therefore, a haze boundary region is introduced to generate a smoother transition from haze to clear areas. Two transition methods with a leveled boundary are presented: with fixed weighting and with histogram-dependent weighting. Additionally, the image is corrected atmospherically to remove the remaining atmospheric influence and obtain ground reflectance data. Copyright (C) 1996 Elsevier Science Ltd