光谱学与光谱分析
光譜學與光譜分析
광보학여광보분석
SPECTROSCOPY AND SPECTRAL ANALYSIS
2015年
2期
557-562
,共6页
王书民%张爱武%胡少兴%王京萌%孟宪刚%段乙好%孙卫东
王書民%張愛武%鬍少興%王京萌%孟憲剛%段乙好%孫衛東
왕서민%장애무%호소흥%왕경맹%맹헌강%단을호%손위동
高光谱相机%转扫%几何校正%老司城遗址
高光譜相機%轉掃%幾何校正%老司城遺阯
고광보상궤%전소%궤하교정%로사성유지
Hyperspectral camera%Rotating scan%Geometric correction%Lao Si Cheng ruin
针对转扫式光谱成像系统在数据采集过程中,由于转台转速过快造成校正后的影像存在有数据漏洞,以及获取的原始影像数据存在有严重几何形变,影响影像上地物信息的分类与识别等问题,介绍了转扫式光谱成像系统的组成并给出数据采集一般过程,根据数据采集时单帧影像的覆盖范围和系统采集影像的速率等信息,在数据采集时对转台速度进行控制;结合影像获取时的起始与终止角度以及传感器距离前视点的距离等信息,详细推导了转扫式光谱成像空间定位模型,并对定位后影像进行格网划分和光谱重采样,给出了影像畸变校正的一般流程;鉴于影像空间定位后相邻帧间影像空间分辨率不一致,同时为保证获取最大的影像分辨率,采用最小空间采样间隔作为坐标定位后影像格网划分单元;考虑到新生成均匀格网与不均匀格网叠加进行光谱取值时,采用直接光谱采样可能造成的光谱混叠失真问题,提出了基于位置分布的光谱精确采样方法,以张家界老司城获取的高光谱影像数据为例进行畸变的校正,校正后影像上地物保持了原有的几何特征,验证了算法的正确性,同时抽取不同地物点的光谱数据进行相关系数计算,结果表明改进的光谱采样算法优于直接光谱采样,为同类产品的地面应用提供参考。
針對轉掃式光譜成像繫統在數據採集過程中,由于轉檯轉速過快造成校正後的影像存在有數據漏洞,以及穫取的原始影像數據存在有嚴重幾何形變,影響影像上地物信息的分類與識彆等問題,介紹瞭轉掃式光譜成像繫統的組成併給齣數據採集一般過程,根據數據採集時單幀影像的覆蓋範圍和繫統採集影像的速率等信息,在數據採集時對轉檯速度進行控製;結閤影像穫取時的起始與終止角度以及傳感器距離前視點的距離等信息,詳細推導瞭轉掃式光譜成像空間定位模型,併對定位後影像進行格網劃分和光譜重採樣,給齣瞭影像畸變校正的一般流程;鑒于影像空間定位後相鄰幀間影像空間分辨率不一緻,同時為保證穫取最大的影像分辨率,採用最小空間採樣間隔作為坐標定位後影像格網劃分單元;攷慮到新生成均勻格網與不均勻格網疊加進行光譜取值時,採用直接光譜採樣可能造成的光譜混疊失真問題,提齣瞭基于位置分佈的光譜精確採樣方法,以張傢界老司城穫取的高光譜影像數據為例進行畸變的校正,校正後影像上地物保持瞭原有的幾何特徵,驗證瞭算法的正確性,同時抽取不同地物點的光譜數據進行相關繫數計算,結果錶明改進的光譜採樣算法優于直接光譜採樣,為同類產品的地麵應用提供參攷。
침대전소식광보성상계통재수거채집과정중,유우전태전속과쾌조성교정후적영상존재유수거루동,이급획취적원시영상수거존재유엄중궤하형변,영향영상상지물신식적분류여식별등문제,개소료전소식광보성상계통적조성병급출수거채집일반과정,근거수거채집시단정영상적복개범위화계통채집영상적속솔등신식,재수거채집시대전태속도진행공제;결합영상획취시적기시여종지각도이급전감기거리전시점적거리등신식,상세추도료전소식광보성상공간정위모형,병대정위후영상진행격망화분화광보중채양,급출료영상기변교정적일반류정;감우영상공간정위후상린정간영상공간분변솔불일치,동시위보증획취최대적영상분변솔,채용최소공간채양간격작위좌표정위후영상격망화분단원;고필도신생성균균격망여불균균격망첩가진행광보취치시,채용직접광보채양가능조성적광보혼첩실진문제,제출료기우위치분포적광보정학채양방법,이장가계로사성획취적고광보영상수거위례진행기변적교정,교정후영상상지물보지료원유적궤하특정,험증료산법적정학성,동시추취불동지물점적광보수거진행상관계수계산,결과표명개진적광보채양산법우우직접광보채양,위동류산품적지면응용제공삼고。
As the rotation speed of ground based hyperspectral imaging system is too fast in the image collection process,which exceeds the speed limitation,there is data missed in the rectified image,it shows as the black lines.At the same time,there is serious distortion in the collected raw images,which effects the feature information classification and identification.To solve these problems,in this paper,we introduce the each component of the ground based hyperspectral imaging system at first,and give the general process of data collection.The rotation speed is controlled in data collection process,according to the image cov-er area of each frame and the image collection speed of the ground based hyperspectral imaging system,And then the spatial ori-entation model is deduced in detail combining with the star scanning angle,stop scanning angle and the minimum distance be-tween the sensor and the scanned object etc.The oriented image is divided into grids and resampled with new spectral.The gen-eral flow of distortion image corrected is presented in this paper.Since the image spatial resolution is different between the adja-cent frames,and in order to keep the highest image resolution of corrected image,the minimum ground sampling distance is em-ployed as the grid unit to divide the geo-referenced image.Taking the spectral distortion into account caused by direct sampling method when the new uniform grids and the old uneven grids are superimposed to take the pixel value,the precise spectral sam-pling method based on the position distribution is proposed.The distortion image collected in Lao Si Cheng ruin which is in the Zhang Jiajie town Hunan province is corrected through the algorithm proposed on above.The features keep the original geomet-ric characteristics.It verifies the validity of the algorithm.And we extract the spectral of different features to compute the corre-lation coefficient.The results show that the improved spectral sampling method is better than the direct sampling method.It provides the reference for the similar product used on the ground.