Research On The Method Of 3D Data Measurement Based On Structured Light

3D data measurement which is an important subject in the research of Computer Vision is wide used in many areas such as VR (virtual reality), antique protection, film industry, manufacture industry, CAD, CAM and clothing industry etc. Among the methods of 3D data measurement, the method based on structured light is a popular and promising subject, and it is in great need at present because it can get accurate 3D data from an object cheaply without contacting it. Consequently, it is significant in theory and practice to study on this method.The status of 3D data measurement at present has been analyzed detailedly and the method of 3D data measurement based on structured light has been studied systemicly in this paper, including the measurement principle, system calibration, image raster extracting and indexing, 3D data integration etc. The main work of thispaper is as follows:1. The method of 3D data measurement based on parallel structured light ispresented in this paper, in which the homograph theory is used to compute 3D coordinates of an object without calibrating the camera.2. The measurement principle and the calibration of the measurement system arestudied in this paper. The recalibration of the measurement system based on document [40] is discussed in theory, in order to decrease the workload when the camera parameters are changed in measurement.3. Much work has been done on the research of image raster extracting andindexing: in the study on extracting and indexing of the color raster, Canny edge detector is used to extract raster edge and the gradient information is used to index; the method of extracting and indexing of the black and white raster is presented, which is based on the principle of extracting and indexing of the color raster. In this method the contrast between the images of the object under the white light and under the raster light is used to extract image raster, and the relation matrix which describes the relation of the raster is used to index; in the study on extracting and indexing of the subdivision pattern raster, only the unpolluted edge is extracted every time, in order to eliminate wrong index.4. In the study on edge locating of image raster, Canny edge detector is used to locate the raster edge accurately. In the study on noise elimination, the method of region-grow is used to eliminate noise. Experiments show our methods are effective.5. In the study on 3D data integration by turntable, one method based on vanishing point is presented, which can compute the rotation angle of the turntable from the image, and the other method based on correlation is discussed in theory.