机载激光雷达数据辅助的航空高光谱影像几何精校正
|
摘要
严格的几何精校正可以提高遥感影像的实用价值。对于CASI(compact airborne spectrographic imager)推扫式单线阵航空高光谱传感器而言,由于每次飞行装机都要重新安装GPS(global positioning system)接收机、差分定位与惯性测量单元(inertial measurement unit,IMU),因此GPS、IMU和传感器之间的几何方位标定并不严格,从而导致外方位元素精度受到影响,几何校正结果不理想。为提高几何校正精度,需要依据共线方程,结合地面控制点,计算相应的辅助校正参数。然而实验区属于高海拔无人区,难以实施地面控制点测量,且无其他高精度正射影像可参考。为此实验以机载LiDAR(light detection and ranging)数据为辅助,一方面基于LiDAR高程信息生成数字高程模型;另一方面,通过对LiDAR回波强度信息进行校正,提高基于回波强度的地物判读性,并以回波强度图为参考选取控制点。然后,结合控制点和数字高程模型,完成了CASI高光谱影像的几何精校正。通过对航带间同名地物点坐标对比,证明其精度得到了很大提高。结果表明,利用LiDAR回波强度信息可以解决控制点缺少的问题,显著提高遥感图像几何校正精度,未来也可在地物分类等方面发挥更大作用。
Geometric precision correction is very important for improving the quality of remote sensing images.CASI( compact airborne spectrographic imager) is an airborne 1-dimensional pushbroom sensor,and must be integrated with GPS( global positioning system) receiver and IMU( inertial measurement unit) before performing data acquisition. Each time CASI is installed on airplane with GPS and IMU,the geometric parameters among them must be got precisely. Usually obtained by manual measurement,which is not a very accurate way,values of these parameters are not precise,which means the precision of exterior orientation elements is influenced,and finally lead to errors of geometric correction results. According to the collinear equation,which is the basic principle of geometric correction,auxiliary correction parameters should be applied to exterior orientation elements,and these can be calculated by taking some ground control points as reference. For the study area is depopulated,it's hard to survey ground control points in field,and also there is no other high spatial resolution orthoimage which can be used,so how to get control points is the key problem. Li DAR( light detection and ranging) data contain many kinds of information,such as 3-dimensional coordinates,echo intensity,echo number. Li DAR data synchronously acquired with CASI was used from two aspects. First,the DEM of study area was produced mainly based on 3-dimensional coordinates. Besides that,the intensity image was also generated based on the echo intensity after it was calibrated,of which the main purpose was to improve its interpretation of ground objects. Then some control points were chosen by taking the Li DAR intensity image as reference. Combined with DEM and these control points,geometric precision correction of CASI image was completed. Through comparison of the coordinates of corresponding image points in two adjacent strips before and after correction aided by control points,the results showed that the geometric precision had been improved obviously. This experiment proves that making full use of other information in Li DAR data,such as intensity,can do much more work in remote sensing image processing.
Geometric precision correction is very important for improving the quality of remote sensing images.CASI( compact airborne spectrographic imager) is an airborne 1-dimensional pushbroom sensor,and must be integrated with GPS( global positioning system) receiver and IMU( inertial measurement unit) before performing data acquisition. Each time CASI is installed on airplane with GPS and IMU,the geometric parameters among them must be got precisely. Usually obtained by manual measurement,which is not a very accurate way,values of these parameters are not precise,which means the precision of exterior orientation elements is influenced,and finally lead to errors of geometric correction results. According to the collinear equation,which is the basic principle of geometric correction,auxiliary correction parameters should be applied to exterior orientation elements,and these can be calculated by taking some ground control points as reference. For the study area is depopulated,it's hard to survey ground control points in field,and also there is no other high spatial resolution orthoimage which can be used,so how to get control points is the key problem. Li DAR( light detection and ranging) data contain many kinds of information,such as 3-dimensional coordinates,echo intensity,echo number. Li DAR data synchronously acquired with CASI was used from two aspects. First,the DEM of study area was produced mainly based on 3-dimensional coordinates. Besides that,the intensity image was also generated based on the echo intensity after it was calibrated,of which the main purpose was to improve its interpretation of ground objects. Then some control points were chosen by taking the Li DAR intensity image as reference. Combined with DEM and these control points,geometric precision correction of CASI image was completed. Through comparison of the coordinates of corresponding image points in two adjacent strips before and after correction aided by control points,the results showed that the geometric precision had been improved obviously. This experiment proves that making full use of other information in Li DAR data,such as intensity,can do much more work in remote sensing image processing.
引文
1李爱农,边金虎,靳华安,等.山地遥感[M].北京:科学出版社,2016:81-102Li Ainong,Bian Jinhu,Jin Huaan,et al.Mountain remote sensing[M].Beijing:Science Press,2016:81-102
2李德仁,童庆禧,李荣兴,等.高分辨率对地观测的若干前沿科学问题[J].中国科学:地球科学,2012,42(6):805-813Li Deren,Tong Qingxi,Li Rongxing,et al.Current issues in highresolution earth observation technology[J].Science China Earth Sciences,2012,42(6):805-813
3李爱农,边金虎,张正健,等.山地遥感主要研究进展、发展机遇与挑战[J].遥感学报,2016,20(5):1199-1215Li Ainong,Bian Jinhu,Zhang Zhengjian,et al.Progresses,opportunities,and challenges of mountain remote sensing research[J].Journal of Remote Sensing,2016,20(5):1199-1215
4 Zhu S L,Shi W Z,Zhang Y,et al.Precision comparison of several algorithms for approximate rectification of linear array push-broom imagery[J].Journal of Remote Sensing,2004,8(3):220-226
5 Weser T,Rottensteiner F,Willneff J,et al.Development and testing of a generic sensor model for push-broom satellite imagery[J].Photogrammetric Record,2008,23(123):255-274
6唐新明,张过,祝小勇,等.资源三号测绘卫星三线阵成像几何模型构建与精度初步验证[J].测绘学报,2012,41(2):191-198Tang Xinming,Zhang Guo,Zhu Xiaoyong,et al.Triple linear-array imaging geometry model of Ziyuan-3 surveying satellite and its validation[J].Acta Geodaetica et Cartographica Sinica,2012,41(2):191-198
7潘红播,张过,唐新明,等.资源三号测绘卫星传感器校正产品几何模型[J].测绘学报,2013,42(4):516-522Pan Hongbo,Zhang Guo,Tang Xinming,et al.The geometrical model of sensor corrected products for Ziyuan-3 satellite[J].Acta Geodaetica et Cartographica Sinica,2013,42(4):516-522
8 Nagasubramanian V,Radhadevi P V,Ramachandran R,et al.3Dreconstrution with rational function model[J].Journal of the Indian Society of Remote Sensing,2008,36(1):27-35
9朱述龙,史文中,张艳,等.线阵推扫式影像近似几何校正算法的精度比较[J].遥感学报,2004,8(3):220-226Zhu Shulong,Shi Wenzhong,Zhang Yan,et al.Precision comparison of several algorithms for approximate rectification of linear array push-broom imagery[J].Journal of Remote Sensing,2004,8(3):220-226
10张剑清,潘励,王树根.摄影测量学[M].武汉:武汉大学出版社,2002:12-15Zhang Jianqing,Pan Li,Wang Shugen.Photogrammetry[M].Wuhan:Wuhan University Press,2001:12-15
11马伟波,丁建伟,谭琨.定位定向系统数据的航空高光谱影像几何校正[J].测绘科学,2017,42(6):130-136Ma Weibo,Ding Jianwei,Tan Kun.Geometric correction of airborne hyspex hyperspectral image based on POS data[J].Science of Surveying and Mapping,2017,42(6):130-136
12周前飞,刘晶红,居波,等.面阵CCD航空相机斜视图像的几何校正[J].液晶与显示,2015,30(3):505-513Zhou Qianfei,Liu Jinghong,Ju Bo,et al.Geometric correction of oblique images for array CCD aerial cameras[J].Chinese Journal of Liquid Crystals and Displays,2015,30(3):505-513
13 Sithole G,Vosselman G.Experimental comparison of filter algorithms for bare-earth extraction from airborne laser scanning point clouds[J].ISPRS Journal of Photogrammetry and Remote Sensing,2004,59(1):85-101
14 Yoon J S,Shin J I,Lee K S.Land cover characteristics of airborne Li DAR intensity data:a case study[J].IEEE Geoscience and Remote Sensing Letters,2008,5(4):801-805
15 Yan W Y,Shaker A,Habib A,et al.Improving classification accuracy of airborne Li DAR intensity data by geometric calibration and radiometric correction[J].ISPRS Journal of Photogrammetry and Remote Sensing,2012,67(2):35-44
16 Mesas-Carrascosa F J,Castillejo-González I L,Orden M S D L,et al.Combining Li DAR intensity with aerial camera data to discriminate agricultural land uses[J].Computers and Electronics in Agriculture,2012,84:36-46
17伊丕源,童鹏,赵英俊,等.典型地物机载激光雷达测量系统回波强度特征实验分析[J].科学技术与工程,2016,16(16):216-221Yi Piyuan,Tong Peng,Zhao Yingjun,et al.Typical land cover characteristics of airborne Li DAR intensity data:an experimental study[J].Science Technology and Engineering,2016,16(16):216-221
18 H9fle B,Pfeifer N.Correction of laser scanning intensity data:data and model-driven approaches[J].ISPRS Journal of Photogrammetry and Remote Sensing,2007,62(6):415-433
19 Burgess G,Shortis M R,Scott P.Photographic assessment of retroreflective film properties[J].ISPRS Journal of Photogrammetry and Remote Sensing,2011,66(5):743-750
20伊丕源,满旺,童鹏,等.加入地物倾角分析的Li DAR回波强度校正[J].遥感学报,2016,20(4):610-619Yi Piyuan,Man Wang,Tong Peng,et al.Calibration algorithm with object tilt angle analysis and calculation for Li DAR intensity data[J].Journal of Remote Sensing,2016,20(4):610-619
2李德仁,童庆禧,李荣兴,等.高分辨率对地观测的若干前沿科学问题[J].中国科学:地球科学,2012,42(6):805-813Li Deren,Tong Qingxi,Li Rongxing,et al.Current issues in highresolution earth observation technology[J].Science China Earth Sciences,2012,42(6):805-813
3李爱农,边金虎,张正健,等.山地遥感主要研究进展、发展机遇与挑战[J].遥感学报,2016,20(5):1199-1215Li Ainong,Bian Jinhu,Zhang Zhengjian,et al.Progresses,opportunities,and challenges of mountain remote sensing research[J].Journal of Remote Sensing,2016,20(5):1199-1215
4 Zhu S L,Shi W Z,Zhang Y,et al.Precision comparison of several algorithms for approximate rectification of linear array push-broom imagery[J].Journal of Remote Sensing,2004,8(3):220-226
5 Weser T,Rottensteiner F,Willneff J,et al.Development and testing of a generic sensor model for push-broom satellite imagery[J].Photogrammetric Record,2008,23(123):255-274
6唐新明,张过,祝小勇,等.资源三号测绘卫星三线阵成像几何模型构建与精度初步验证[J].测绘学报,2012,41(2):191-198Tang Xinming,Zhang Guo,Zhu Xiaoyong,et al.Triple linear-array imaging geometry model of Ziyuan-3 surveying satellite and its validation[J].Acta Geodaetica et Cartographica Sinica,2012,41(2):191-198
7潘红播,张过,唐新明,等.资源三号测绘卫星传感器校正产品几何模型[J].测绘学报,2013,42(4):516-522Pan Hongbo,Zhang Guo,Tang Xinming,et al.The geometrical model of sensor corrected products for Ziyuan-3 satellite[J].Acta Geodaetica et Cartographica Sinica,2013,42(4):516-522
8 Nagasubramanian V,Radhadevi P V,Ramachandran R,et al.3Dreconstrution with rational function model[J].Journal of the Indian Society of Remote Sensing,2008,36(1):27-35
9朱述龙,史文中,张艳,等.线阵推扫式影像近似几何校正算法的精度比较[J].遥感学报,2004,8(3):220-226Zhu Shulong,Shi Wenzhong,Zhang Yan,et al.Precision comparison of several algorithms for approximate rectification of linear array push-broom imagery[J].Journal of Remote Sensing,2004,8(3):220-226
10张剑清,潘励,王树根.摄影测量学[M].武汉:武汉大学出版社,2002:12-15Zhang Jianqing,Pan Li,Wang Shugen.Photogrammetry[M].Wuhan:Wuhan University Press,2001:12-15
11马伟波,丁建伟,谭琨.定位定向系统数据的航空高光谱影像几何校正[J].测绘科学,2017,42(6):130-136Ma Weibo,Ding Jianwei,Tan Kun.Geometric correction of airborne hyspex hyperspectral image based on POS data[J].Science of Surveying and Mapping,2017,42(6):130-136
12周前飞,刘晶红,居波,等.面阵CCD航空相机斜视图像的几何校正[J].液晶与显示,2015,30(3):505-513Zhou Qianfei,Liu Jinghong,Ju Bo,et al.Geometric correction of oblique images for array CCD aerial cameras[J].Chinese Journal of Liquid Crystals and Displays,2015,30(3):505-513
13 Sithole G,Vosselman G.Experimental comparison of filter algorithms for bare-earth extraction from airborne laser scanning point clouds[J].ISPRS Journal of Photogrammetry and Remote Sensing,2004,59(1):85-101
14 Yoon J S,Shin J I,Lee K S.Land cover characteristics of airborne Li DAR intensity data:a case study[J].IEEE Geoscience and Remote Sensing Letters,2008,5(4):801-805
15 Yan W Y,Shaker A,Habib A,et al.Improving classification accuracy of airborne Li DAR intensity data by geometric calibration and radiometric correction[J].ISPRS Journal of Photogrammetry and Remote Sensing,2012,67(2):35-44
16 Mesas-Carrascosa F J,Castillejo-González I L,Orden M S D L,et al.Combining Li DAR intensity with aerial camera data to discriminate agricultural land uses[J].Computers and Electronics in Agriculture,2012,84:36-46
17伊丕源,童鹏,赵英俊,等.典型地物机载激光雷达测量系统回波强度特征实验分析[J].科学技术与工程,2016,16(16):216-221Yi Piyuan,Tong Peng,Zhao Yingjun,et al.Typical land cover characteristics of airborne Li DAR intensity data:an experimental study[J].Science Technology and Engineering,2016,16(16):216-221
18 H9fle B,Pfeifer N.Correction of laser scanning intensity data:data and model-driven approaches[J].ISPRS Journal of Photogrammetry and Remote Sensing,2007,62(6):415-433
19 Burgess G,Shortis M R,Scott P.Photographic assessment of retroreflective film properties[J].ISPRS Journal of Photogrammetry and Remote Sensing,2011,66(5):743-750
20伊丕源,满旺,童鹏,等.加入地物倾角分析的Li DAR回波强度校正[J].遥感学报,2016,20(4):610-619Yi Piyuan,Man Wang,Tong Peng,et al.Calibration algorithm with object tilt angle analysis and calculation for Li DAR intensity data[J].Journal of Remote Sensing,2016,20(4):610-619