仪器仪表学报
儀器儀錶學報
의기의표학보
CHINESE JOURNAL OF SCIENTIFIC INSTRUMENT
2014年
z1期
1-8
,共8页
航空遥感%面阵CCD图像%几何校正%误差分析
航空遙感%麵陣CCD圖像%幾何校正%誤差分析
항공요감%면진CCD도상%궤하교정%오차분석
aerial remote sensing%array CCD images%geometric distortion correction%error analysis
文章主要讨论了面阵CCD航空相机斜视摄影中所获取图像的几何畸变校正及其误差分析问题。由于斜视成像过程中飞机姿态和相机成像方位的变化,使图像存在严重的几何变形,文章根据面阵CCD航空相机成像过程中的几何关系,说明了基于共线方程的几何校正算法原理,重点对校正后图像的几何失真误差进行了分析,建立了该几何校正算法的误差传递模型,分析了图像几何畸变校正精度与各姿态角的测量精度、相机相对地面高度的测量精度的关系。若使图像校正达到像素级精度(2~3 pixels),对于1k×1k pixels图像,各姿态角的测量精度至少应达到6′,对于2k×2k pixels图像,各姿态角的测量精度至少应达到3′;对于1k×1k pixels图像,取基准航高为2000m,要使图像比例尺归一化过程的均方根误差小于2 pixels,航高测量误差应小于5m。通过实际航拍图像的校正实验验证了几何校正方法以及误差分析的正确性。
文章主要討論瞭麵陣CCD航空相機斜視攝影中所穫取圖像的幾何畸變校正及其誤差分析問題。由于斜視成像過程中飛機姿態和相機成像方位的變化,使圖像存在嚴重的幾何變形,文章根據麵陣CCD航空相機成像過程中的幾何關繫,說明瞭基于共線方程的幾何校正算法原理,重點對校正後圖像的幾何失真誤差進行瞭分析,建立瞭該幾何校正算法的誤差傳遞模型,分析瞭圖像幾何畸變校正精度與各姿態角的測量精度、相機相對地麵高度的測量精度的關繫。若使圖像校正達到像素級精度(2~3 pixels),對于1k×1k pixels圖像,各姿態角的測量精度至少應達到6′,對于2k×2k pixels圖像,各姿態角的測量精度至少應達到3′;對于1k×1k pixels圖像,取基準航高為2000m,要使圖像比例呎歸一化過程的均方根誤差小于2 pixels,航高測量誤差應小于5m。通過實際航拍圖像的校正實驗驗證瞭幾何校正方法以及誤差分析的正確性。
문장주요토론료면진CCD항공상궤사시섭영중소획취도상적궤하기변교정급기오차분석문제。유우사시성상과정중비궤자태화상궤성상방위적변화,사도상존재엄중적궤하변형,문장근거면진CCD항공상궤성상과정중적궤하관계,설명료기우공선방정적궤하교정산법원리,중점대교정후도상적궤하실진오차진행료분석,건립료해궤하교정산법적오차전체모형,분석료도상궤하기변교정정도여각자태각적측량정도、상궤상대지면고도적측량정도적관계。약사도상교정체도상소급정도(2~3 pixels),대우1k×1k pixels도상,각자태각적측량정도지소응체도6′,대우2k×2k pixels도상,각자태각적측량정도지소응체도3′;대우1k×1k pixels도상,취기준항고위2000m,요사도상비례척귀일화과정적균방근오차소우2 pixels,항고측량오차응소우5m。통과실제항박도상적교정실험험증료궤하교정방법이급오차분석적정학성。
The paper concerns the error analysis of image geometric distortion correction for oblique images of array CCD aerial camera. The attitude variation of airplane and the image orientation change of aerial camera in squint mode will cause the captured images to be severely distorted.Based on the imaging geometry of squint mode of array CCD aerial cameras,the theory of geometric correction method based on the colineare quation of perspective projection is illustrated.Especially,the errors of geometric distortion correction are analyzed. The error transfer model in geometric correction were established to analyse the correlation between the image correction precision and the accuracy of attitude angles and flight height.To achieve pixel level correction accuracy such as 2 or 3 pixels, the accuracy of attitude angles should reach 6 minutes for 1k × 1k pixels image and 3 minutes for 2k × 2k pixels image; to make the mean-square-root error of normalization in image scale less than 2 pixels, the accuracy of flight height shoud be less than 5 meters for 1k × 1k pixels image when the benchmark flight height is 2000 meters. Experiments carried out on aerial images confirm the effectiveness of the method and error analysis of the geometric distortion correction.