Key Technologies Of Close Range Photogrammetry Based On Multipletexture

Close range photogrammetry based on multiple texture is a complementarity and extention for existing close range photogrammetry system.It can measure those objects which lack of grain or hard to stick retro-reflective targets on objects surface.Considering this situation, this paper do some research on the key technic of texture based close range photogrammetry. Primary coverage of the dissertation was as follows:The development status of photogrammetry and several famous photogrammetry system are introduced.The background and meaning of research on nature texture based and projected texture based close range photogrammetry is put forward.A new comprehensive conner points sorting method is put forward. Methods of image feature point extraction is compared using designed experiment. An adaptive threshold method is put forward to overcome some disadvantages when using in actual application.Existing image feature matching methods are compared,and the depth of measured object restriction condition is put forward to match image points through 3-D coordinate restriction.A detail matching scheme is put forward to calculate the detail of objects surface.Three different kind of projected feature extraction method is researched,and the design and matching is achieved.A Harris operator based is put forward to extract grid like projected texture more reliably.The experiment result prove its feasibility.Absolute orientation method and relative orientation method are presented.Two different kind orientation device is designed and made to cooperate with nature texture and projected texture based close range photogrammtry.Finally,several instance of nature texture and projected texture based close range photogrammetry are presented to explain the measuring objects and its application domain.