CAJ | 학술논문

针对海洋合成孔径雷达(SAR)图像结构信息不明显、水下目标识别困难这一问题,提出了基于经验模式分解(EMD)的算法和H(o)lder指数调整相融合的框架,该框架可以有效地滤除海洋SAR图像的斑点噪声并增强其结构信息,使得人眼可以分辨其特征信息.该融合框架利用EMD将海洋SAR图像分解成不同频率成分的分量,不同层次的分量根据其结构信息和噪声的特征用不同的H(o)lder指数来调整,H(o)lder指数的大小随着分量层数的增加而减小,即在不同尺度下分别抑制斑点噪声,从而恢复其中所包含的结构信息.试验结果表明,利用该框架可以有效抑制SAR图像中的斑点噪声和增强与水下目标相关的结构信息,使人眼可以分辨海洋SAR图像的特征结构.
침대해양합성공경뢰체(SAR)도상결구신식불명현、수하목표식별곤난저일문제,제출료기우경험모식분해(EMD)적산법화H(o)lder지수조정상융합적광가,해광가가이유효지려제해양SAR도상적반점조성병증강기결구신식,사득인안가이분변기특정신식.해융합광가이용EMD장해양SAR도상분해성불동빈솔성분적분량,불동층차적분량근거기결구신식화조성적특정용불동적H(o)lder지수래조정,H(o)lder지수적대소수착분량층수적증가이감소,즉재불동척도하분별억제반점조성,종이회복기중소포함적결구신식.시험결과표명,이용해광가가이유효억제SAR도상중적반점조성화증강여수하목표상관적결구신식,사인안가이분변해양SAR도상적특정결구.
To solve the problem that underwater objects are difficult to recognize with the method of Synthetic Aperture Radar (SAR) due to the insufficiency of the structure character information of sea SAR images, the paper proposes a noise elimination algorithm based on combining the experiment mode decomposition (EMD) algorithm with the H(o)lder Exponent adjustment. The algorithm can effectively suppress the speckle noise and enhance the structure character information, which finally become visible to the naked eye. Using the different frequency character of each level, the content of each level noise and non-noise are analyzed and the H(o)lder exponent of each level is adjusted. And the speckle noise of simple SAR images in different scale is filtered. At last, the new denoised SAR images can be obtained. The experimental result indicates that the speckle noise is substantially decreased and the structure character and texture of the result is clearer. And human eyes can distinguish the structure character of sea SAR images.