计算机仿真
計算機倣真
계산궤방진
COMPUTER SIMULATION
2010年
3期
215-219
,共5页
葛任伟%吴清文%王运%颜昌翔
葛任偉%吳清文%王運%顏昌翔
갈임위%오청문%왕운%안창상
联合变换相关器%像移测量%傅立叶变换%质量中心算法
聯閤變換相關器%像移測量%傅立葉變換%質量中心算法
연합변환상관기%상이측량%부립협변환%질량중심산법
Joint transform correlator%Image motion measurement%Fourier transform%Centre of mass calculation
为了测量由卫星姿态不稳定或振动等原因引起的空间相机亚像元像移,对基于联合变换相关器的像移测量方法进行了研究,并进行计算机仿真.阐述了该方法的数学原理,面阵CCD的安装位置以及输入图像序列的获取方法.应用MatLab对图像进行线性插值获得具有亚像元像移的图像,并添加噪声使图像具有较低信噪比;对图片进行傅立叶变换得到联合功率谱.二值化处理后的功率谱再次进行傅立叶变换得到相关输出;用质量中心算法计算出像移量.结果表明,像移测量的精度不随景物的内容而变化,测量得到的像移误差均方根误差值小于0.2个像元.
為瞭測量由衛星姿態不穩定或振動等原因引起的空間相機亞像元像移,對基于聯閤變換相關器的像移測量方法進行瞭研究,併進行計算機倣真.闡述瞭該方法的數學原理,麵陣CCD的安裝位置以及輸入圖像序列的穫取方法.應用MatLab對圖像進行線性插值穫得具有亞像元像移的圖像,併添加譟聲使圖像具有較低信譟比;對圖片進行傅立葉變換得到聯閤功率譜.二值化處理後的功率譜再次進行傅立葉變換得到相關輸齣;用質量中心算法計算齣像移量.結果錶明,像移測量的精度不隨景物的內容而變化,測量得到的像移誤差均方根誤差值小于0.2箇像元.
위료측량유위성자태불은정혹진동등원인인기적공간상궤아상원상이,대기우연합변환상관기적상이측량방법진행료연구,병진행계산궤방진.천술료해방법적수학원리,면진CCD적안장위치이급수입도상서렬적획취방법.응용MatLab대도상진행선성삽치획득구유아상원상이적도상,병첨가조성사도상구유교저신조비;대도편진행부립협변환득도연합공솔보.이치화처리후적공솔보재차진행부립협변환득도상관수출;용질량중심산법계산출상이량.결과표명,상이측량적정도불수경물적내용이변화,측량득도적상이오차균방근오차치소우0.2개상원.
To measure the sub-pixel image motion which is caused by satellite attitude instability or vibration,the joint transform correlator method was used and simulated.The mathematics principles were clarified,the position of matrix CCD on the focal plane and the method of getting input image were presented.Based on MatLab,sub-pixel image motion was oblained by linear interpolation and noise has been added to get low SNR image.The input image was Fourier transformed to get the spectrum image,binary image was resulted from the spectrum image and Fourier transformed again to obtain the correlation image,and the corresponding shift value was calculated with centre of mass calculation.The results show that the error does not change with different scene of input images,and the error RMS of 0.2 can be achieved.