CONTENIDO
1. OPEN SOURCE SOFTWARE AND GIS 1
Open Source concept 1
GRASS as an Open Source GIS 3
How to read this book 4
2. PREREQUISITES TO USE GRASS 7
Hardware and software requirements 7
UNIX basics 8
What is UNIX? 8
Login and X Window 9
Managing files 11
Running applications 15
Downloading and installing GRASS 19
3. GIS CONCEPTS AND GRASS 21
General GIS principles 21
Geospatial data models 21
Organization of GIS data 25
GIS functionality 26
Introduction to GRASS 27
Organization of the Grass database 27
Command structure 29
A short GRASS sample session 31
GRASS file management 34
4. PLANNING A GRASS DATABASE 39
Map projections and coordinate systems 39
Map projection principles 40
Geographic coordinate system: latitude-longitude 43
Universal Transverse Mercator Grid System 44
Lambert Conformal Conic Projection based systems 44
Gauss-Kruger Grid System 45
North American and European Datums 46
Working with different projections in GRASS 47
Creating a new LOCATION 47
Coordinate system transformations 54
5. WORKING WITH RASTER DATA 59
GRASS raster data model 59
Import and export of raster data 63
Importing raster data 63
Importing and geocoding of scanned maps 67
Exporting raster data 73
Viewing and managing raster map layers 73
Displaying raster data and assigning a color table 74
Raster map queries and profiles 75
Zooming and generating subsets from raster maps 76
Managing metadata of raster maps 78
Reclassification of raster maps 79
Assigning category labels 82
Masking and handling of no-data values 85
Raster map algebra 87
Raster data transformation and interpolation 94
Automated vectorization of discrete raster data 94
Generating isolines representing continuous fields 95
Raster data transformation to sites model 96
Interpolation of raster data and resampling 97
Recoding of raster map types and value replacements 99
Spatial analysis with raster data 100
Map statistics and neighborhood analysis 100
Overlaying and merging raster maps 104
Buffering of raster features 107
Cost surfaces 108
DEM and watershed analysis 112
Landscape structure analysis and modeling 118
6. WORKING WITH VECTOR DATA 121
GRASS vector data model 121
Importing and exporting vector data 123
Importing vector data 123
Exporting vector data 131
Digitizing vector data 133
General principles for digitizing topological data 134
Digitizing in GRASS 135
Metadata and attributes management 141
Managing metadata of vector maps 142
Map attributes modifications 142
Viewing and analysis 143
Displaying vector map layers 143
Intersecting and clipping vector maps 144
Map reclassification 146
Feature extraction from vector data 147
Vector data transformation to/from raster and sites 148
Automatic vectorization of raster data 148
Discrete transformation of vector data to raster or sites 150
Interpolating raster surfaces from contour lines 151
7. WORKING WITH SITE DATA 155
GRASS site data model 155
Importing, creating and exporting sites 156
Importing site data 156
Digitizing site data 158
Generating site data within GRASS 159
Exporting site data 160
Viewing and managing site data 160
Displaying site data and creating subsets 161
Computing basic statistics 161
Transformation from sites to rasters and spatial interpolation 163
Selecting an interpolation method 163
Interpolating with RST: tuning the parameters 167
Estimating accuracy 171
Interpolating large data sets 172
Surfaces with faults 175
Adding third variable: precipitation with elevation 178
Volume and volume-temporal interpolation 178
Geostatistics and splines 180
8. GRAPHICAL OUTPUT AND VISUALIZATION 183
Two-dimensional display and animation 183
Displaying map layers using the GRASS monitor 183
Creating a 2D shaded elevation map 186
Monitor output to PNG and HTML files 187
Animations in 2D space 189
Visualization in 3D space with NVIZ 190
Viewing multiple map layers 190
Querying and analyzing data in NVIZ 195
Creating animations in 3D space 196
Visualizing volumes 201
Creating hardcopy maps 203
Map generation with ps.map 203
Map design with Xfig and Sketch 204
9. SATELLITE IMAGE PROCESSING 207
Remote sensing basics 207
Spectrum and remote sensing 207
Satellite sensors 209
Satellite data import and export 212
Import of raw and geocoded satellite data 212
Export of multi-channel data sets 215
Understanding a satellite data set 215
Managing channels and colors 215
The feature space and image groups 219
Geometric and radiometric preprocessing 221
Geometric preprocessing 221
Radiometric preprocessing 228
Application: Deriving a surface temperature map from thermal channel 234
Radiometric transformations and image enhancements 236
Image ratios 236
Principal Component Transformation 237
Fourier Transformation 239
Geometric feature analysis 243
Matrix filter: Spatial convolution filtering 243
Edge detection 245
Image fusion 246
Introduction to RGB and IHS color model 247
RGB color composites 248
Image fusion with IHS transformation 249
Image fusion with Brovey transformation 251
Thematic reclassification of satellite data 252
Unsupervised radiometric reclassification 254
Supervised radiometric reclassification 258
Supervised SMAP reclassification 261
10. PROCESSING OF AERIAL PHOTOS 263
Introduction to aerial photogrammetry 263
Orthophoto generation 266
From aerial photo to orthophoto 266
Aerial photo and LOCATIONs preparation 268
Orthophoto generation 270
Segmentation and pattern recognition for aerial images 278
11. NOTES ON GRASS PROGRAMMING 281
GRASS programming environment 281
Methods of GRASS programming 282
Level of integration 283
Script programming 283
Automated usage of GRASS 290
Notes on programming GRASS modules in C 292
12. USING GRASS: APPLICATION EXAMPLES 299
Erosion risk in Spearfish area 299
Computation of the LS factor 300
Estimating R, K, and C factors 305
Computing and analyzing erosion risk 306
GIS modeling for land management 309
Building the GIS database 310
Deriving new map layers 316
Land use analysis, problems and solutions 324
13. USING GRASS WITH OTHER OPEN SOURCE TOOLS 335
Geostatistics with GRASS and gstat 336
Spatial data analysis with GRASS and R 341
Spearfish data set analysis 343
Maas river bank soils data analysis 351
Using R in batch mode 361
GPS data handling 363
Maps in WWW: MapServer 364
References 369
Appendices 377
A Summary of important GRASS commands 377
A.1 Display commands 377
A.2 General commands 379
A.3 Image processing commands 380
A.4 Miscellaneous and map projection commands 381
A.5 Postscript and PPM driver commands 382
A.6 Raster data commands 383
A.7 Site data commands 387
A.8 Vector data commands 388
B Supported GIS formats and projections 391
B.1 Supported GIS data formats in GRASS 391
B.2 List of supported ellipsoids, datums and projections 392
C Customizing Grass by environment variables 95
D Usage UNIX text tools for GIS data preparation 399
E Selected equations used in GRASS modules 403
E.1 Basic Statistics 403
E.2 Interpolation 404
E.3 Topographic analysis 405
E.4 Insolation 410
F MapServer sample configuration 415
F.1 MapServer definition file 415
F.2 MapServer HTML template 418
Index 421