Research On Key Techniques Of Oral Microscopic Stereo Vision

Oral microscopy has great application value and broad application prospects in oral teaching,surgery and other environments,so it is of great practical significance to study oral microscopy.Binocular stereo vision is performed by simulating both eyes through a computer and some peripherals.The three-dimensional information of the observed object is obtained through series calculation.The microscopic stereo vision is to adjust and modify the binocular system.The two objective lenses of the stereo microscope act as binoculars.Two observation angles in the system complete the reconstruction of three-dimensional information in the microscopic environment.The microscopic stereo vision system can be divided into four parts:image acquisition,camera calibration,stereo matching and 3D reconstruction.In this subject,the image acquisition part connects two CCD industrial cameras to the two eyepieces of the stereo microscope,and transmits the image information to the computer through USB to achieve real-time image observation information collection.The main work of the thesis includes the following points.(1)Microenvironment camera calibration.By comparing the micro camera model with the common camera model,the specialty of the micro camera calibration is obtained.After that,the acquisition method which is most suitable for the microscopic environment calibration image is summarized by many experiments.Finally,the error screening method is proposed in this paper.The comparison proves that the error screening can reduce the calibration error by about 6%on the basis of the calibration method.(2)Stereo matching.Image correction is performed on the stereo image pair,so that the image pair satisfies the limit constraint criterion,and then the similarity calculation is performed by using the image region gradation correlation to obtain a disparity map of the stereo image pair.After comparing the different window sizes and different maximum and minimum parallaxes,the corresponding parallax images are obtained,and the most suitable matching parameters are determined by comparing the score maps.In this paper,the three-dimensional measurement of the known parameters on the calibration plate is used to verify the correctness of the calibration results of the above microscope.(3)Three-dimensional reconstruction.The parallax map obtained by stereo matching performs binocular visual depth of field calculation.Since the three-dimensional point cloud model synthesized under a single viewing angle has some defects,the multi-view model fusion method is used for data compensation to obtain the final microscopic binocular system.The model renderings achieve the purpose of the oral microscopic stereo vision system.