SIDESCAN SONAR IMAGE PROCESSING: CORRECTING BRIGHTNESS VARIATION AND PATCHING GAPS

NCU Institutional Repository > 地球科學學院 > 地球科學學系 > 期刊論文 > Item 987654321/50550

請使用永久網址來引用或連結此文件: http://ir.lib.ncu.edu.tw/handle/987654321/50550

題名:	SIDESCAN SONAR IMAGE PROCESSING: CORRECTING BRIGHTNESS VARIATION AND PATCHING GAPS
作者:	Chang,YC;Hsu,SK;Tsai,CH
貢獻者:	地球科學系
日期:	2010
上傳時間:	2012-03-27 17:36:37 (UTC+8)
出版者:	國立中央大學
摘要:	Sidescan sonar data are typically presented as gray level images. However, sidescan images often show striking variations in brightness. These variations, caused by the sonar beam pattern and the constantly changing attitude of the towfish, make the images difficult to read as pictures of the seabed. This reduces the utility of the images for marine geologists. In this paper, the effects of the sonar beam pattern across the swath are corrected using a normalization process based on the average signal intensity for each grazing angle. Noise along the track, which is generally caused by changes in the attitude of the towfish, is eliminated using an assumption that the total back-scattered energy from each ping should be similar to adjacent pings in the time series. These two processes allow the production of smooth and clear waterfall displays. However, when the sidescan data are projected onto a map as a high resolution "mosaic" image, gaps appear on the outer edge of the swath where the towfish changes course. To remove the gaps, a patching algorithm is proposed. The patching method is justified theoretically by the shape of the sonar footprint on the sea floor. All the pixels falling inside the sonar footprint can be assigned reasonable values using just the original data series, with no need for interpolation.
關聯:	JOURNAL OF MARINE SCIENCE AND TECHNOLOGY-TAIWAN
顯示於類別:	[地球科學學系] 期刊論文

文件中的檔案:

檔案	描述	大小	格式	瀏覽次數
index.html		0Kb	HTML	639	檢視/開啟

在NCUIR中所有的資料項目都受到原著作權保護.

社群 sharing

資料載入中.....