gvSIG یک بسته نرم افزاری توسعه داده شده توسط CIT (مخفف Regional Council for Infrastructures and Transportation ) با همکاری Jaume I University وIVER Tecnologias de la Informacionَ تحت زبان جاوا در محیط توسعه Eclipse و انتشاریافته تحت مجوز GPL می باشد. این نرم افزار قابلیت اجرا در هر سکویی که Java Virtual Machine امکان نصب دارد، اعم از Windows، Linux، Mac و … را داراست. در حال حاضر رابط کاربری آن در زبان های Spanish, Valencian, English, Basque, Gallego, Czech, Chinese, French, German, Italian, Romanian, Polish و Portuguese موجود است. در این نرم افزار به طور عمده از کتابخانه های GeoTools، JTS و GDAL استفاده شده است.
جدول زیر جنبه های مختلف عملکرد این نرم افزار را فهرست می کند. از آنجایی که قسمت مهمی از توان gvSIG در تجزیه و تحلیل داده ها مبتنی بر بسط SEXTANTE است، عملکرد آن به طور جداگانه در جدول بعدی آورده شده است.
عملکرد نرم افزار gvSIG
| WMS, WFS, WCS, Catalogue Service, Gazetteer Service,Geography Markup Language, Web Map Context, Style Layer Descriptor,Filter enconding | استانداردهای پشتیبانی شده |
| Vector data: .shp, .gml, .kml, .dgn v7, .dxf (texto), .dwg (2000, R14, R13 and R12)Raster data: .ecw, .tiff (geotif, tfw), .jpg, .png, .gif, MrSID, .img, .jpeg2000, .bmpTable data: file-based(.csv, .dbf) and Database (PostgreSQL, MySQL, GBMS-HSQLDB, Oracle, ODBC) | فرمت ورود داده ها |
| .shp, .gml, .kml, GeoTIFF, ECW (only in Linux kernel 2.4), JPEG (georeferenced), JPEG2000 (georeferenced), dxf (version 7), Postgis | فرمت صدور داده ها |
| Pan, Zoom, information tool, Measure distance and area, Selection tools, Locate by attribute | ابزارهای استاندارد |
| Vector layers: Changing colors, Using hyperlik, Legend editing (unique symbols, unique values, intervals), LabelingRaster Layers: Get general information, Set bands, Set transparency, Modify brightness & contrast, Enhancement (Remove edges, tail trimming), PanSharping (increase resolution of satellite images if panchromatic band is available) | توانایی های بصری سازی (Visualization) |
| Select by layer, Select by attribute, searching catalog server for geodata, searching Gazetteer server for location of address, Georefrencing rasters, table Statistics, Field calculator, Editing tools, Map preparation for printing, Geoprocessing tools for vector layers(Buffer, Clipping, Dissolve, Merge, Convex Hull, Intersection, Difference, Union, Spatial Join, 2D translation, Reprojection) | ابزارها و تحلیل های پیشرفته |
| Jython, javascript, beanShell and groovy | زبان های اسکریپت نویسی |
| ArcSDE Client: Vector Layers only.ArcIMS client: ImageServer (adding selected set of layers), FeatureServer (addition of remote vector layers)3D Pilot: creation of 3D views, XYZ-projected and spherical (planetary)CRS module: use of the complete EPSG, IAU2000, and others, transformation of 3 and 7 parameters and also the grid based ones
Extension to synchronize with gvSIG Mobil: exporting information directly from gvSIG desktop to gvSIG Mobile, including layer information and (simplified) symbols. In addition, the extension creates the project file which is opened in gvSIG Mobile. geoDB extension: access to spatial databases including PostGIS and Oracle Spatial & Locator -in reading and writing mode-, and MySQL and HSQLDB -only in reading mode-. Network pilot: generation network topology and calculation of a minimum path Publishing extension: publishing geospatial data and metadata through standard OGC web services, now through MapServer(WMS, WCS & WFS) and GeoServer(WFS) softwares Raster pilot: Apply color palettes to a DTM, compute histograms, cut out raster layers, visualization filters. SEXTANTE: raster and vector geographical analysis capabilities with over 200 extensions listed below. These analyses can be run independently graphically or command-line oriented or together in a model by providing a model creation tool |
بسط های افزودنی (Extension) |
عملکرد نزم افزار SEXTANTE
| Analytical Hierarchy Process (AHP), Change Vector Analysis, Ordered Weighted Averaging (OWA) , Predictive models, Soft classification, Supervised Classification, Unsupervised classification (clustering) | Analysis tools for raster layer |
| Channel network, Flow accumulation, Sink filling, Time to outlet, Aslope area from a single point, Watersheds | Basic hydrological analysis |
| Aggregate, Basic statistics, Change data type, Complete grid, Correlation between layers, Crop grid with polygon layer, Crop to valid data cells, Density, Density (kernel), Export raster layer, Gradient lines, Invert mask, Merge grids, Mirror/flip, Normalize, Sort, User-defined 3 X 3 filter, Void filling, Void filling [nearest neighbour], Volume calculation, Volumen between two layers, | Basic tools for raster layers |
| Buffer, Threshold buffer | Buffers |
| Raster calculator | Calculus tools for raster layer |
| Accumulated cost (anisotropic), Accumulated cost(isotropic), Cost in predefined routes, Generate alternative routes, Least cost path, Polar to rect, Rect to polar, Sum of cost to all points | Costs, distances and routes |
| Equal values count (neighbourhood), Kurtosis (neighbourhood), Larger values count (neighbourhood), Lower values count (neighbourhood), Maximum (neighbourhood), Mayority (neighbourhood), Mean (neighbourhood), Median (neighbourhood), Minimum (neighbourhood), Minority (neighbourhood), Radius of variance, Range (neighbourhood), Skeweness (neighbourhood), Variance (neighbourhood) , | Focal statistics |
| Fuzzify | Fuzzy logic |
| Anisotropic coefficient of variation, Aspect, Convergence index, Curvatures, Elevation-relief ratio, Hypsometry, Landform classification, Protection index, Real area, Slope | Geomorphometry and terrain analysis |
| Semivariances (raster) | Geostatistics |
| Calibrate an image, Calibrate an image (regression), Contrast stretching, Detect and vectorize individual trees, Equalize, Erosion/Dilation, HIS -> RGB, RGB -> HIS, Thinning | Image processing |
| C factor from NDVI, Distance to channel network, Edge contamination, Elevation over channel network, Max. value uphill, Mean value uphill, Net balance, Slope length, Strahler Order, Topographic indices | Indices and other hydrological parameters |
| Equal values count, Kurtosis, Larger values count, Lower values count, Maximum, Maximum value layer, Majority, Mean, Median, Minimum, Minimum value layer, Minority, Range, Skewness, Variance | Local statistics |
| Location/allocation | Location/allocation |
| Diversity, Dominance, Fragmentation, Number of different classes | Pattern analysis |
| Distance matrix, Mean center and standard distance, Median center, Nearest neighbour analysis, Quadrant analysis, Ripley’s K, Spatial autocorrelation | Point analysis |
| Cross sections, Flow line profile, Profile | Profiles |
| Constant grid, Grid from function, Random DEM, Random grid (Bernouilli), Random grid (normal), Random grid (uniform) | Raster creation tools |
| Inverse distance, Kriging, Linear decrease, Nearest neighbour, Rasterize vector layer, Universal Kriging, | Rasterization and interpolation |
| Bernouilli probability distribution, Chi squared probability distribution, Covariance matrix, Exponential probability distribution, Multiple regression, Normal probability distribution, Principal Components Analysis, Regression, Student’s t probability distribution | Statistical methods |
| Basic statistics, Correlation between fields, Save as CSV | Table tools |
| Aggregation index, Class statistics, Combine grids, Cross checking(Kappa index), Divide in n classes of equal amplitude, Divide in n classes of equal area, Filter clumps, Fragstats (area/density/edge metrics), Fragstats (diversity metrics), Grids from table and classified grid, Reclassify, Reclassify in disjoint classes, Reclassify in ordered classes | Tools for categorical raster layers |
| Adjust n point to polygon, Basic statistics, Box-whisker plot, Buffer, Centroids, Change line direction, Clasificar(cluster) espacialmente, Cluster, Correlation between fields, Cortar, Count points in polygons, Create graticule, Directional mean, Export vector layer, Field calculator, Geometric properties of polygons, Grid statistics in polygons, Lines to equispaced points, Merge, Minimum enclosing shapes, New layer with selected shapes, Point statistics in polygons, Points layer from table, Polygons to polylines, Polylines to polygons, Sample raster layers, Select by point, Select by query, Select by rectangle, Select with additional layer, Separate entities, Simplify lines, Sinuosity, Transform | Tools for vector layers |
| Contour lines, Raster layer to points layer, Vectorize raster layer (lines), Vectorize raster layer (polygons), | Vectorization |
| CTVI, NDVI, NRVI, PVI(Perry and Lautenschlager), PVI(Qi et al), PVI(Richardson and Wiegand), PVI(Walther and Shabaani), TTVI, TVI | Vegetation indices |
| Line of sight, Shaded relief, Solar radiation, Visibility, Visual exposure | Visibility and lighting |
همچنین gvSIG ورژن ساده شده ای را برای سیستم های موبایل با سیستم عامل Windows Mobile فراهم آورده است. gvSIG ورژن موبایل قادر به پشتیبانی Shapefile، ECW، WMS و تصاویر و استفاده از سیستم های GPS است. در حال حاضر تنها امکان نمایش لایه های فوق و تولید نقاط مسیر (Waypoints) از روی GPS وجود دارد.
علاوه بر آن، به دلیل اتکای gvSIG به موتور JVM ورژن قابل حمل و بدون نیاز به نصب آن برای درایو های USB (حافظه هایFlash ) موجود است.
