Research On Geometric Correction Method Of DMZ ? Image For New Aerial Camera

With the rapid development of microelectronics technology and the progress of mapping technology,that has become the inevitable trend of historical development to the traditional aerial film camera been replaced multi-area CCD aerial camera,but due to the manufacturing process limitations of CCD,digital aerial Image been generated by a single CCD,the size of the image can't be achieved to the original analog camera image size,which greatly affected the digital aerial camera photography efficiency and mapping accuracy.In order to solve this problem,many researchers at home and abroad put forward the concept of multi-area CCD camera.The multi-area camera is divided into two categories: outer field of view composite and inner field of view composite according to the number of the lens and the final synthesis principle of the image.Which outer field of view composite camera is bundled by multiple small and medium sized camera.The advantage of this type of camera is that the system is extremely simple,the disadvantage when in the formation of equivalent center projection virtual image,there is a theoretical approximation,but the elevation accuracy is relatively low.The inner field of view composite camera is strictly in accordance with the traditional single-lens imaging system,the principle of strict center projection relationship,the main difference is that the focal plane been divided by a number of the array components in space,in principle of formation image is basically the same with the classic frame camera.The preprocessing technology of inner field composite multi-area CCD camera has become the hotspot of photogrammetry research.Radiation correction and geometric correction are the main components of multi-aerial camera image preprocessing.In this paper,the system geometric correction system of the new composite large area array CCD aerial camera(DMZ II)is studied.The geometric calibration parameters of the DMZ II are calibrated by the laboratory,and the geometric correction parameters are calculated according to their own characteristics of formation image.The validity and feasibility of the method are verified by the test data.The main contents of this paper:1.The research status of geometric processing of aerial camera is introduced.Introduced the DMZ II camera system,and pointed out the importance of system geometric correction in its preprocessing components.2.The principle of DMZ II geometric of formation image is expounded.Although it is completely satisfied with the central projection relationship,it is necessary to correct the error of the optical splitter in order to satisfy the high precision of mapping because of its introduction of the optical splitter.In order to eliminate such errors,several mature geometric correction methods are introduced: translation transformation,two-dimensional isometric transformation,affine transformation,projection transformation and polynomial transformation,and illustrate the characteristics of different transformation models.3.The process of geometric calibration of DMZ II is introduced,and the parameters of system geometric correction are obtained by high precision angle measurement data,which includes: transforming model parameters and lens distortion parameters.According to the algorithm of this paper,a geometric correction application has been developed.4.The geometric correction parameters of the system are used to solve the airborne test data.The lens distortion is calibrated by the self-calibration beam method.