The key operation in airports extraction from remote sensing images is to extract the airport edges and obtain their approximate strait lines. For example, the Canny can be used to extract image edges and the result edges can be used to obtain approximate strait lines by Hough Transform or other strait line fitting methods. However, background of airport target is so complex that large numbers of useless edge pixels will be extracted from surroundings by Canny algorithm and those disheveled edge pixels will interfere with the following analysis. For example, it is difficult to use Hough Transform to extract useful strait lines of airport edges from the binary image composed of airport edges and other useless edge pixels because the proportion of disheveled edges is far larger than the one of airport edges. One solution is to smooth the image before edges detection. Unfortunately, most of image smoothing operation cannot weaken useless edges effectively. Moreover, it will also damage the useful ones and makes it more difficult to extract useful strait lines. Though some edge-preserve smoothing algorithms have been proposed, it is still difficult to solve this problem because too many disheveled but robust edges will be preserved together. In this paper, a novel edge-preserve image smoothing algorithm based on Convexity Model is discussed with its practical application in airport extraction. This smoothing algorithm will whittle or restrain those regions whose features accord with the Convexity Model and whose sizes are smaller than the specified one. The experimental results show that the algorithm is effective in removing noises and small regions with few influences on those edges of interested targets whose scales are larger than the specified one. The practical applications show that this smoothing algorithm can increase the efficiency and precision of airports extraction.

Date Published: 8 August 2007
PDF: 11 pages
Proc. SPIE 6752, Geoinformatics 2007: Remotely Sensed Data and Information, 67520M (8 August 2007); doi: 10.1117/12.760448

Published in SPIE Proceedings Vol. 6752:
Geoinformatics 2007: Remotely Sensed Data and Information
Weimin Ju; Shuhe Zhao, Editor(s)