Papers by Keyword: Quad-Tree Decomposition

Abstract: In this study, a weight switching tri-state median filter (TSM) is proposed for removing impulse noise in both smooth and complicated regions of the dealing images. The switching scheme adopted large center weight while removing impulse noise of the complicate regions and switched to small center weight while dealing with the smooth regions. The smooth and complicated regions were classified according to the statistics information of the dealing image. The quad-tree decomposition was used to reduce classification procedures. Simulation results demonstrate that the proposed center weight switching scheme makes the TSM effective in both smooth and complicated regions of images with different noise ratio.

Abstract: A new reversible watermarking algorithm for image authentication, which embeds authentication information into the sub-band coefficients after lifting wavelet transform by using the difference expansion method, is proposed in this paper. Block map, after quad-tree decomposition, is used to represent the whole characteristic of image content and embed it into the original image as watermark information. Experiments results show that the proposed scheme can restore the image reversibly and has good ability to detect and locate vicious tamper.

Abstract: Rural roads construction projects are expensive, this has led to difficulties in developing accurate construction plans and modeling the construction operation using a novel simulation system. In this field, the aim of this research is to create a knowledge driven rural road construction simulation system to assist satellite image in generating s and reliable road construction plans. Road construction operations of the resources have been identified, developed, classified and modeled through a comprehensive analysis of a Simulink road construction projects. For every road construction operation a GIS-based template for little models was defined and developed. The models abridge distance of the path on the roads construction between villages and automating the optimizing of works. Also, the models provide a roadmap for evaluating several shortest paths on road construction via Quad-tree decomposition of the satellite image. A simulation case study was modeled to identify applicability, usefulness and accuracy of the developed simulation system and results are presented in this paper. The study fulfilled that the system generated for fast marching.

Abstract: In this article, a new method for rapid tool movement in CNC machines is presented. Firstly, a single digital camera, installed on the Z-axis, captures the image of the workpiece on the work table. Image processing techniques, implemented using MATLAB, are then used to convert the image into a binary black and white image. This allows the locations of protruding edge sections on the workpiece, which could impede tool movement, to be identified. Quadtree decomposition is then performed on the binary image, and possible paths from the tool current location to its target location are found. These paths are then analysed based on the tool diameter clearance and the distance to the goal, and the shortest path with sufficient tool clearance is selected. A Visual Basic program then converts the selected path into G-code commands that provides instructions to the CNC machine tool such that this path is followed. With this method, the workpiece fixture location would not have to be precise as the imaging system would be able to automatically identify the target location with respect to the tool current location, along with the optimal path to reach it.