Study On The Key Technology For Images Stitching Of Large Format Digital Multi-images Based On Axis-Shift

With the development of the equipment of aerial photogrammetry and the key technologies of aerial photogrammetric image processing,aerial remote sensing plays an increasingly important role in obtaining geographic data.Aerial photography system origin from the analog measurement and analytical photogrammetry has been developed to a multi-faceted,digitized,multi-camera professional aerial photogrammetry system with airborne Positioning and Orientation System.The appearance of large format aerial photography equipment solves the problem that the traditional single-lens aerial photography equipment has narrow field of view,low efficiency and low elevation accuracy,among which digital aerial photography equipment based on axis-shift imaging has become hot research field of aerial photogrammetry both at home and abroad.It brings new problems that the different ways of imaging methods,lens combinations,image mosaic of large format digital camera is quite unlike the past.This paper focuses on the large format digital camera system based on the axisshift imaging.This camera system consists of four groups of lenses and nine shift-axis full-color sensors.Nine sets of axis-shift images is necessary to be projected into the virtual camera plane of the digital camera system to form a large format digital images.The study of image preprocessing of single lens camera system,calibration of common camera,image stitching of tilt combined has been carried out in-depth study,but the research of calibration of shift-axis camera and its relative orientation,image stitching of shift axis combination and other key technologies is not deeply studied in China.Based on the axis-shift multi-camera structure and the imaging system of the camera system,this paper proposes the stitching model of the combined large format digital image based on axis-shift imaging,and puts forward an self-calibration image stitching method with calibration parameters.The calibration experiments of dual camera system,the ground experiment of dual camera system,aerial flight test of dual camera system and the simulation experiment of nine aerial images is designed to verify the reliability and usability of the model proposed.The corresponding program to realize the image automatic splicing process is developed and it was applied to practical.