A Preliminary Study On 3D Reconstruction Of Inner Decay In Log Cross-section Based On 2D Image Of Stress Wave

Forest reserves have been decreasing year by year with the over-exploitation and over-utilization of forest resources without good planning in recent several decades. Nevertheless, the requirement of wood products has been increasing, so this will result in a serious contradiction between wood supply and demand. Therefore, how to high-efficiency and low-consumption utilize the scarce wood resources is currently one of the major research issues in forestry academic area. However, nondestructive detecting the inner decay of wood to get comprehensive information is the foundation of making reasonable utilization plan. Accordingly, the three-dimensional (3D) reconstruction of inner decay in log cross-section was realized to accurately determine the log internal construction with the help of Matlab software, so as to provide theoretical foundation and scientific basis for log defects detecting, log reasonable classifying and bucking, auto-producing, standing tree health assessing, and wooden building strength evaluating. Additionally, these researches are very significant to effective utilize forest resources, reduce wood loss and waste and improve log utilization rate.3D reconstruction technology provides the realistic 3D graphics for users through obtaining 3D structural information from the two-dimensional (2D) sequence images of objects, so as to easily observe and analyze the 3D image from multi-view point and multi-level and greatly improve the accuracy and scientific of detectionFirstly, the stress wave 2D image of log inner dacay was getten using ARBOTOM detecting system based on ananlyzing propagation thoery of stess wave. Secondly, the 2D image was pre-processed applying the image processing technique to filter the image noise and artifact image, so that the information of inner decay is more clear and easily identified. Then, the pre-processed 2D image was reasonable separated, and the boundary contour and innner decay edge of log were extracted by edge detection operator. Finally, for the better display effects of 3D reconstruction, this research used the layer interpolation algorithm generating the interpolation image, reducing the distance of layers and creasing the number of image. And the 3D reconstruction surface rendering and volume rendering of inner decay in log cross-section were realized for log defects detecting with the help of the Matlab software. The reconstruction method which was applied in this research is very simple, easy programming and has better display effects. As well as, the 2D image pre-processing, image segmentation and layer interpolation were also realized by Matlab programming.3D reconstruction based on CT image is a major research content of 3D-data visualization, which has a broad application in geological prospecting, weather forecasting and particularly in the detection area. Therefore, the 3D reconstruction technique has become a new computer stage with the development of computer technology and computer graphics.