จำนวน Repository ( 3 )
การปรับปรุงความคมชัดของภาพ ด้วยการปรับเท่าฮีสโตแกรมด้วยการเปลี่ยนแปลงเวฟเลตสองมิติ
This thesis emphasizes the improvement approaches of quality on digital data to be more sharpness by two- dimensional technique. Today the availability from the improvement of Digital Image Processing is used widely in various occupations such as medical field with reading the results from CT scanning military field with the improvement of aerial map for country prevention agricultural field with leaf analysis of its disease and the educational field with the image processing and robot vision to increase its effective learning and remembering development. It can be seen that the image development through its sharpness is really crucial therefore this thesis used the Gray Scale for transforming by two-dimensional wavelet and LL Band got from this wavelet transform to be improved by histogram technique. The histogram was divided into 4 parts based on its cumulative density at 0.25 0.5 0.75 and 1 then smoothed the data by separation after that brought the results to invert wavelet which gives the new image through improved LL band. The research result revealed that the mean of the Absolute Mean Brightness Error (AMBE) was decreased while enable the image sharpness to suitably increase 80%.
เทคนิคการแบ่งส่วนของข้อมูลภาพเอสเออาร์ด้วยวิธีวอร์เตอร์เฉดและปรับเรียบฮีสโตแกรม
Since the details in quasi-homogeneous region will be degraded from a conventional global image enhancement methods such as histogram equalization. This degradation causes from the saturation of the gray levels in equalization process. Then the local histogram equalization for each quasi-homogeneous region will be used in order to improve the details in the regions. To obtain the quasi-homogeneous regions the image can be segmented by using a watershed transform. The watershed transform is based on mathematical morphology; therefore the segmented regions can be effectively separated meaningful. Two adjacent regions in images which almost similar in gray levels can be separted by the watershed transform. In the color image enhancement three spectral bands are enhanced independently. Then all the three bands are assigned to each processed image in order to produce a color composite image. By the proposed algorithm the result images show the better perception on image details. Therefore the high efficiency of image classification can be obtained by using this color image.
Semi-automatic mapping of electric poles using sfm technique
The objective of this research is to proposed a semi-automatic method for mapping electric poles using the structure from motion technique or SFM. First an epipolar geometry for each image pair is estimated. Then the 3D structures are obtained using incremental SFM technique which will give us both 3D point cloud of the study area and camera parameters. Also vertical 2D lines are extracted from the input images. These 2D lines and the 3D structures are then integreated for estimating the positions of electric pole in 3D space. Finally these 3D electric poles are then geo-registered by estimating 3D rigid transformation from embeded coordinates in the input images.