Date of Award
Spring 5-2011
Degree Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Computing
School
Computing Sciences and Computer Engineering
Committee Chair
Benjamin Seyfarth
Committee Chair Department
Computing
Committee Member 2
Dia Ali
Committee Member 2 Department
Computing
Committee Member 3
Beddhu Murali
Committee Member 3 Department
Computing
Committee Member 4
Ras Pandey
Committee Member 4 Department
Physics and Astronomy
Committee Member 5
Chaoyang Zhang
Committee Member 5 Department
Computing
Abstract
The process of creating aerial photo mosaics can be severely affected by clouds and the shadows they create. In the CZMIL project discussed in this work, the aerial survey aircraft flies below the clouds, but the shadows cast from clouds above the aircraft cause the resultant mosaic image to have sub-optimal results. Large intensity variations, caused both from the cloud shadow within a single image and the juxtaposition of areas of cloud shadow and no cloud shadow during the image stitching process, create an image that may not be as useful to the concerned research scientist. Ideally, we would like to be able to detect such distortions and correct for them, effectively removing the effects of the cloud shadow from the mosaic.
In this work, we present a method for identifying areas of cloud shadow within the image mosaic process, using supervised classification methods, and subsequently correcting these areas via several image matching and color correction techniques. Although the available data contained many extreme circumstances, we show that, in general, our decision to use LIDAR reflectance images to correctly classify cloud and not cloud pixels has been very successful, and is the fundamental basis for any color correction used to remove the cloud shadows. We also implement and discuss several color transformation methods which are used to correct the cloud shadow covered pixels, with the goal of producing a mosaic image which is free from cloud shadow effects.
Copyright
2011, Glover Eugene George
Recommended Citation
George, Glover Eugene, "Cloud Shadow Detection and Removal from Aerial Photo Mosaics Using Light Detection and Ranging (LIDAR) Reflectance Images" (2011). Dissertations. 522.
https://aquila.usm.edu/dissertations/522