000			03642nam a2200205Ia 4500
999			_c56759 _d56759
008			191023s9999 xx 000 0 und d
082			_aMG TH-0183 _bSON
100			_aSoni, Siddharth (PT201517) _970930
245		0	_aFeature extraction from point cloud generated using UAV based photogrammetry (Softcopy is also available)
260			_c2019
300			_aii,iv,xv,60p.
505			_aTable of Contents Certificate of Original Authorship i Certificate of Dissertation - Advisor’s consent iii Certificate of Dissertation - Program Chair v Acknowledgments vii Abstract ix List of figures xi List of tables xv 1 INTRODUCTION 1 1.1 Drone Survey 2 1.1.1 Orthomosaic 3 1.1.2 Point Cloud 3 1.1.3 DEM and DSM 3 1.1.4 Textured Mesh 3 1.2 Research Problems 4 1.2.1 Complex Scene 4 1.2.2 Lack of Conformity 4 1.2.3 Complex Geometry 4 1.3 Goal and Objectives 5 1.4 Scope and Limitations 5 1.5 Need for Study 6 1.6 Thesis Outline 6 2 LITERATURE REVIEW 9 2.1 Building Detection from Satellite Images 9 2.2 Building Detection from Aerial Images 10 2.3 Building Detection from High Density Point Clouds 11 2.4 Conclusions 12 3 DATA ACQUISITION AND PROCESSING IN DRONE SURVEY 13 3.1 Ground Control Points 13 3.2 Flight Parameters 14 3.2.1 Camera Specifications 14 3.2.2 Flight Path 15 3.2.3 Flight Height 16 3.2.4 Front and Side Lap 16 3.3 Understanding Spatial Resolution with Drones 17 3.4 Processing of Data 18 3.4.1 Preprocessing of Images 19 3.4.2 Structure from Motion Algorithm 19 3.4.3 3D Scene Reconstruction 21 4 POINT CLOUD PROCESSING 23 4.1 Types of Point Cloud 23 4.1.1 LiDAR 24 4.1.2 Digital Aerial Photogrammetry 25 4.2 Point Feature Representation 26 4.2.1 Normal Estimation 26 4.2.2 Curvature 27 4.2.3 Point Feature Histograms 28 4.3 Point Cloud Segmentation 28 4.4 Plane Extraction in Point Clouds 28 4.4.1 Region Growing based Method 29 4.4.2 Random Sample Consensus 29 4.4.3 Hough Transform 30 4.5 Multi-view Registration of Point Cloud 30 5 RESEARCH METHODOLOGY 31 5.1 Forming Neighbourhoods 31 5.2 Tabulate Local Feature Descriptors 32 5.2.1 Surface Normals 32 5.2.2 Surface Density 32 5.2.3 Volume Density 33 5.2.4 Curvature 33 5.2.5 Roughness 33 5.3 Segregate Ground Points and Non Ground Points 33 5.3.1 Cloth Simulation Filter 33 5.3.2 Progressive Morphological Filter 34 5.4 Plane Segmentation using RANSAC 35 5.5 Identifying Connected Components 35 5.6 Edge Points Detection 36 5.7 Boundary Approximation Using Regularization Constraints 36 5.8 Roof Modelling 36 5.9 Generating DEM and Contour from Ground Points 37 6 DATASET 39 6.1 Initial Image Positions 40 6.2 Geolocation Details 41 6.3 Point Cloud Densification and DSM Details 41 6.4 Subset of Data 42 7 RESULTS AND OUTPUTS 43 7.1 Point Cloud Data Formats 43 7.2 Local Feature Representations 44 7.2.1 Surface Normals 44 7.2.2 Number of Neighbours 45 7.2.3 Curvature 46 7.2.4 Roughness 47 7.3 Segregating Ground Points and Non-Ground Points 47 7.4 Plane Extraction 48 7.5 Edge Point Detection and Boundary Regularization 49 7.6 DEM and Contour Generation 50 7.7 Reconstructed Urban Scene 52 7.8 Comparison with other methods 53 8 CONCLUSION 55 References 57 Appendix 59
700			_aReddy, Chetan (Guide) _970931
700			_aShroff, Vichar (Guide) _970932
700			_aVyas, Anjana (Guide) _970933
890			_aIndia
891			_a2017 Batch
891			_aFT-PG
891			_aM.Sc. Geomatics