Astrostatistics Image Penn State University Eberly College of Science Center for Astrostatistics Center for Astrostatistics

Spatial statistics & image analysis

The following are metasites to vast resources in the areas of pattern recognition, classification, neural networks, perceptrons, machine vision and learning, data mining, and image processing:

AI-GEOSTATS software & shareware archive
    This is a very large metasite operated by the European Comission Joint Research Centre providing extensive links to software used in geostatistics, geographic information systems, landscape analysis, and related fields. The most commonly used method is kriging, giving optimal prediction and extrapolation of 2- and 3-dimensional unevenly-spaced data, including quantitative estimation of the uncertainty at each point. Examples of the codes linked by AI-GEOSTATS include:

    Large package in C designed for hydrogeologists histograms and plots, varograms and cross-variograms, jackknifing uncertainty estimates, kriging, 3-dimensional visualization of scattered data.

Geographic Resources Analysis Support System (GRASS)
    Comprehensive Geographic Information System (GIS) used for geospatial data management and analysis, image processing, graphics/maps production, spatial modeling, and visualization.

Generic Mapping Tools (GMT)
    Collection of 50 UNIX tools for 2- and 3-dimensional datasets with filtering, spline and nearest neighbor estimation, filtering, many projections and contouring. Produces EPS illustrations.

Geostatistical Software Library (GSLIB)
    Fortran code under UNIX for 2- and 3-dimensional geostatistics including many krigings with uncertainties estimated by simulated annealing, cross-validation and jackknifing. PostScript outputs.

Neighborhood EM (NEM)
    Clustering and classification of spatial data based on EM Algorithm implementation of a penalized likelihood statistic. Code in C.

Computer Vision source codes
    Impressive metasite with links to many image processing packages including: SatherVision (object oriented environment); SUSAN algorithms (structure-preseving smoothing, edge/corner detection); GSnake (contour modeling, extraction/detection), Object Recognition Toolkit (progressive edge detection); Steerable Pyramid (multiscale, multiorientation wavelet-based image decomposition); MMach (mathematical morphology toolbox within Khoros, with dilation and erosion); KLT (feature tracker for registration of overlapping images); MeasTex (texture classification). Provides links to toolkits within specific environments (KHOROS, X11/Motif, Vista, Tcl/Tk, MatLab, Macintosh, OpenGL), tool libraries for specific image formats (JPEG, TIFF, MPEG), and codes for image synthesis by ray tracing.

Hypermedia Image Processing Reference
    Tutorial materials in image processing and machine vision concentrating on ~50 image processing operations: image arithmetic, geometric operations; shape analysis; smoothing, denoising, Fourier and other digital filters; edge and feature detection and classification; dilation erosion, segmentation and skeletonization: distance, Fourier and Hough transforms.  HIPR provides information, Java demonstrations, student exercises, image library, detailed glossary & index, bibliography and software.  From the Dept. of Artificial Intelligence at the University of Edinburgh.

Morphometrics software
    Site providing information and software relating to mathematical morphometrics including: multivariate regression of shape and unwarping of images using thin-plate splines; N-dimensional image rotation and superimposition; shape analysis using landmarks; outline detection; analysis of outlines using Fourier analysis, eigenshape analysis and fractal analysis; image enhancements; and more.  From The Biological Sciences at SUNY Stony Brook.

    A library of R modules for statistical analysis of spatial point processes. Includes simulation, summary statistics (empty space, nearest neighbour, Ripley's K, J, and pair correlation functions), maximum-likelihood parametric modelling (inhomogeneous Poisson, Strauss, pairwise interaction, and user specified processes). By Adrian Baddeley of the Univ. Western Australia. 

    Collection of methods in C for statistical pattern recognition through classification of multidimensional continuous features. Includes several classifier paradigms (k-nearest neighbor, radial basis function network, Parzen window, Q* algorithm), feature selection strategies and criteria (estimated minimal error probability, inter-class distance, probabilistic distance), feature extraction (inear discriminant analysis, principal component analysis, Sammon mapping), cross-validation error estimation and more.

NPT (N-PoinT spatial statistics)
    Fast implementation of n-point spatial statistics using KD Trees. Includes 2-point correlation function, pruned trees,   Developed for astronomy by the Auton Project (Carnegie-Mellon University) and the PiCA Collaboration.

Spatial autocorrelations
    Highly efficient Matlab and Fortran toolbox for computing simultaneous and conditional spatial autoregressions and mixed regressive spatially autoregressive models, produced by K. Pace of the Dept. of Finance at Lousiana State University.

Gaussian Markov random field simulation
    GMRFsim is a group of C-routines for the fast and exact simulations of general Gaussian random fields on a 2-dimensional lattice and general graph, provided by H. Rue of the Norwegian Institute of Technology. It may be useful both to compare with an observed image or as step in building Bayesian spatial models.

Programs for stochastic geometry
    Codes by Dietrich Stoyan, author of "Stochastic geometry & its applications" (1995): Voronoi 1.0 for 3-dimensional tessellations, STG 4.1 for the simulation and statistical analysis of several models of stochastic geometry; and programs for stereology.

Multiscale analysis
    ADS is a sub-package associated with the multivariate analysis system ADE-4 with multiscale aanalysis and graphical display of spatial point patterns based on Ripley's function K(r).

    Computes voronoi diagrams and Delaunay triangulations. 

    Dirichlet tessellation and Delaunay triangulation of spatial points.  Bu T. R. Turner of University of New Brunswick.

Minimum spanning tree
    Three short codes for the calculation, printing and updating the minimum spanning tree of a multivariate dataset from the journal Applied Statistics are available here, here and here.
Toolkits for manipulating images & converting formats: Toolkits for creating and manipulating graphics: