CAJ | 학술논문

针对单尺度固定函数的滤波器难以有效剔除杂波和提高小弱目标检测性能的不足，文中研究建立多尺度自适应稀疏字典，提出了一种多尺度自适应形态稀疏字典检测小弱目标方法。首先根据图像信号内容建立多尺度自适应形态稀疏字典，并将图像信号在多尺度稀疏字典中进行稀疏分解；然后在分析小原子稀疏表示系数的基础上建立稀疏表示系数直方图，并利用指数函数拟合小尺度原子的稀疏表示系数直方图；最后，根据指数函数拟合参数在杂波、噪声和目标表现出的差异检测小弱目标。该多尺度稀疏字典利用大尺度原子描述图像背景杂波，小尺度原子捕获图像细小特征。实验结果表明，与小波算法和Contourlet算法相比，文中方法能更为有效地抑制背景杂波，减少背景残留，从而提高小弱目标检测性能。
침대단척도고정함수적려파기난이유효척제잡파화제고소약목표검측성능적불족，문중연구건립다척도자괄응희소자전，제출료일충다척도자괄응형태희소자전검측소약목표방법。수선근거도상신호내용건립다척도자괄응형태희소자전，병장도상신호재다척도희소자전중진행희소분해；연후재분석소원자희소표시계수적기출상건립희소표시계수직방도，병이용지수함수의합소척도원자적희소표시계수직방도；최후，근거지수함수의합삼수재잡파、조성화목표표현출적차이검측소약목표。해다척도희소자전이용대척도원자묘술도상배경잡파，소척도원자포획도상세소특정。실험결과표명，여소파산법화Contourlet산법상비，문중방법능경위유효지억제배경잡파，감소배경잔류，종이제고소약목표검측성능。
To overcome the deficiency that the fixed filter with single-scale cannot effectively remove the clutter and improve the performance of dim target detection, a dim target detection method based on a multi-scale adaptive sparse dictionary was proposed in this paper. Firstly, an adaptive multi-scale sparse dictionary was learned based on the sparse coding theory, and the sparse coefficient of the original image at different scales was decomposed. Then exponential fitting function was adopted to fit the statistical sparse representation coefficient histogram at the small-scale atom. Finally, the differences in the exponential fitting function for the target and noise in the multi-scale adaptive sparse dictionary could be extracted and applied to detect the target. This sparse dictionary contained the atoms with different scale, the large-scale atom can describe the background of the image, and the small-scale atom can capture the subtle feature. The results show that this proposed method based multi-scale adaptive sparse dictionary could suppress the clutter more greatly and improve the performance of dim target detection more effectively compared to wavelet and Contourlet method.