Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 8 of 8 for “"watershed segmentation"”.
-
A skin surface characterization system based on capacitive image analysis
… topography, image analysis techniques, such as watershed segmentation and wavelet analysis, have been used to detect the main structures of interest: wrinkles and plateau of the typical micro-relief pattern. In order to validate the method, the features extracted from a dataset of skin …
-
Absolute localization of mobile robots in forest environments by correlating ground LiDAR to overhead imagery
… the centroids of tree crowns extracted using a watershed segmentation algorithm. Matching of the two stem maps is achieved by using a robust Iterative Closest Point (ICP) algorithm that determines the rotation and translation required to align both datasets. The final alignment is used to …
-
GIS-based urban land use characterization and population modeling with subpixel information measured from remote sensing data
… subsequently partitioned by marker-controlled watershed segmentation, leading to an urban land use classification. This new approach is proven to be insensitive to the selection of initial markers as long as they are positioned around the underlying watershed centers. This dissertation links …
-
Development of computer-based algorithms for unsupervised assessment of radiotherapy contouring
… addresses the hypothesis that computational segmentation techniques, with a given prior, can be used to develop an image-based tumour delineation process for contour assessments. This thesis focuses on the exploration of the segmentation techniques to develop an automated method for …
-
Inventorying trees in an urban landscape using small-footprint discrete return imaging lidar
… operations followed by a marker-controlled watershed segmentation were found to perform well (r = 0.82 to 0.92) to delineate individual tree crowns in urban areas, especially when the trees occur in relatively isolated conditions. Using various distribution metrics of lidar returns, random …
-
Permeability, Pore Body, and Pore Throat Size Distributions from 2D Image Analysis: Comparison with Results from 3D Imaging and Laboratory Measurements
… We extend that work based only on porosity segmentation. We estimate pore body and pore throat size distributions, and specific surface area from 2D-images. Then compare those estimates of pore body and pore throat size distributions from thin section to those obtained from 3D imaging, …
-
Procedural analyses of image-based and multiscale investigations of materials
… third objective of this work was to improve the segmentation of multi-sized, irregularly-shaped, and tightly-clustered particles in a 2D image. There are many algorithms to automatically segment features within images, but these algorithms work best for features with uniform sizes and shapes that …
-
New data structure and process model for automated watershed delineation
… the stream network and its associated subwatersheds are the primary steps in the raster-based parameterization of watersheds. There are two widely used methods for delineating subwatersheds. One of these is the Upstream Catchment Area (UCA) method. The UCA method employs a user specified …