| The application prospect of structured light three-dimensional measurement technology to three-dimensional non-contact measurement field is broad. Traditional structured light three-dimensional measurement technology can only obtain the three-dimensional coordinates information of the points on the measured surface. But because many industries have not been satisfied with the 3D figuration information and they also need the color information of the subjects, the color romance technology causes more and more attention and is widely used. So, according to the widespread problem that a color romance method is either inefficient or seriously impacted by the change of light intensity, this thesis proposes a method with highly efficient and which is also free from the influence cased by the change of light intensity.In the process of assigning the color by the existing color romance methods, there are errors caused by the difference of the geometrical properties of the measured surface. In order to reflect the change of the geometrical properties of the measured surface, the measured surface is divided into several sub-units, so the change of the geometrical properties of the measured surface can be considered as the attitude change of the sub-units, which is also can be considered as the change in relative position between the sub-units and the projector as well as the camera. According the position relation mentioned above, the relation between the attitude change of the sub-units and their incident intensity and scattered intensity is analyzed. And combining with the impact of the relation on the color information, a kind of color romance method which is not affected by the incident intensity and the scattered intensity is given in order to eliminate the errors of the color romance brought by the impact of the incident intensity and the scattered intensity. According to the method in this thesis, the emulation measuring system is established and the emulation experiment is executed contra posing the surface with different figure and color. Then the qualitative and quantitative evaluation experiment is executed contra posing the method in this thesis.Contra posing the feature that the romancing method in this thesis uses a sub-unit as a unit to colored the measuring surface, it is found that there a kind of ubiquitous error in at the color junctions of the romancing surface by analyzing. So in order to obtain the high-quality surface, the edge of the color image is located by the color image edge detection method based on color aberration gradient before the color romance. Therefore, the color information of the sub-units at the color junctions is centrally corrected. And then, the correction method is validated by the experiment.The experiment of the color romance is executed contra posing the practice objects with different dimensions, figure and material, which make use of the 3D measured data given by the 3D measurement system. The results show that the incident intensity and the scattered intensity of different parts of the measured surface is uniformly corrected, and the errors of R, G, B which are the color weights are less than 0.02 (the values of R, G, B are restricted between 0 and 1). The human eyes can not distinguish the color error of the romancing surface, because the color resolving power of human eyes is approximately 0.02. So there is a good visual effect on the romancing surface. |
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