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Xian, China

Qin G.-Q.,Zhengzhou University | Zhang Y.-S.,Zhengzhou University | Huang G.-P.,North China University of Water Conservancy and Electric Power | Fan Y.-B.,Troops 61363 | Chen Z.,Troops 66444
Jiliang Xuebao/Acta Metrologica Sinica

With a brief introduction of optical theory of photogrammetry, the relation of the location of datum marks is described in camera lens system between air and underwater. The collinearity theory of underwater photogrammetry is proposed, and the variety of principal distance of underwater camera is illustrated. After the analysis of distortion and view of underwater photography, the camera underwater calibration method is described. One calibration test on underwater camera was done. The results indicate that the collinearity theory of underwater photogrammetry is right and the method of underwater camera calibration is suitable. Source

Li L.,Wuhan University | Yu Z.,Wuhan University | Li Z.,Wuhan University | Xiang Z.,Troops 61363
Wuhan Daxue Xuebao (Xinxi Kexue Ban)/Geomatics and Information Science of Wuhan University

Panoramic maps are usually used to show the landscape from a specific direction and viewing height in a central perspective projection. Regardless of the direction and height, some landscape features may be obscured. In order to improve the visual effect of panoramic maps, a method for local terrain deformation in the horizontal direction based on liquefaction deformation is proposed. This method for reducing local terrain elevation is based on eye tracking, a method that raises the local terrain elevation using a Gaussian transform. This method reduces occlusion and shrinkage phenomenon, enhancing the artistic visual effects of a panoramic map. Source

Fan Y.-B.,Troops 61363 | Huang G.-P.,North China University of Water Conservancy and Electric Power | Yao S.-Y.,Troops 61363 | Ren Z.-G.,Troops 61363
Jiliang Xuebao/Acta Metrologica Sinica

Aimed at the problems that it is lack of the study on camera calibration of more-cameras stereo photogrammetry,and it is no way to satisfy the need of the high precision industrial measurement via the reliability and stability and the precision of the presently technique. Base on the quaternions theory and coplanarity equation,and the new techniques of camera calibration in the trinocular stereo photogrammetry system is proposed,which efficaciously resolves the question of the real-time high precision calibration in industrial field measurement,and the measurement precision of calculated object points coordinates (RMS) is better than ±2 mm,the distance precision is better than ±3 mm in the test. ©, 2015, Chinese Society for Measurement. All right reserved. Source

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