The Research Of 3D Texture Measurement Based On Structed Light

Textures are used to precisely describe the details and the structures of the natural attributes of an objects surface, which is a key factor affecting realistic three-dimensional model. With the rapid development of computer technology and computer graphics, machine vision system also is more and more perfect, which has broad applications in medicine science, culture relics protection, virtual reality and other fields. Texture measurement has become an important means of understanding the world of natural objects through automation technology.Texture measurement is to obtain the true surface texture. Through texture mapping and three-dimensional reconstruction technology, a three-dimensional digital model of texture with true surface texture can be displayed on a computer. In this thesis, a 3D texture measurement technology based on line-structured light is discussed. With a laser sheet beam, a light strip is casted onto a measured-object surface, then video camera obtains a two-dimensional striped image. After a series of algorithm processing, the three-dimensional information of the structure of the light stripes combined with the measurement model and surface texture gray information with texture mapping method can be obtained. Based on the information obtained, a three-dimensional texture model reflecting the real texture of object surface can be reconstructed.First of all, we need to build a measurement platform system. The system is composed of architecture holder, two cameras taking images from different perspectives, three line-lasers, a controlled console and a computer. Camera calibration is an important part in this system which determines the accuracy of the measurement system. This thesis introduces an implicit parameter calibration method which calibrate error coefficient by rotating and moving images. In this measurement system, three line-structured lasers in the same plane vertically illuminate measured object in all directions, two cameras to capture images of light striped outline, and locking in imaging to eliminate background light, are employed. It is need to deal with the captured images by image preprocessing, image calibration reduction, removing noise, filtering, thinning and other image processing. Through texture mapping, the three-dimensional location data of light striped color texture can be extracted. Moving controlled console and repeating the above steps are performed to complete the texture measurements. The program is designed with multi-threading technology. The use of mutex can achieve thread synchronization control. The both greatly improve the measurement efficiency. Finally, based on the method of texture data acquisition in this thesis, it can acquire cloud data which is a series of parallel contours. With the technology of surface reconstruction based on contour stitching with adjacent contour lines of triangulation, three-dimensional texture digital model by OpenGL can be reconstructed.